Ex-Cell-O Machine Tools Style 35 & 35L Precision Thread Grinders - Manual Grinder

'

<

COPYRIGHT 1945

BY EX-CELL-O CORPORATION

DETROIT, MICHIGAN

U. S. A.

PRINTED IN U. S. A.

HFD^

k Jf !■'

a

EX-CELL-O

PRECISION THREAD GRINDERS

3 5 taut/ 3 5 - L

BULLETIN 48141

This manual will prove helpful in obtaining the per

formance that is built into these precision machines.
The operating
the grinder must beset to new work. The information on

thread grinding and grinding wheels will prove valuable.

The maintenance information will be of great assistance

in keeping the thread grinder in continuous operation.

Some details of the machine furnished may differ
from the description of the machine in this book. Con
stant improvements in design and materials, together
with alterations to meet the requirements of individual
customers, are the reasons for such changes.

instructions will be especially usefulwhen





INSTALLATION, OPERATION, AND MAINTENANCE

This book should be placed in the hands

of the proper Supervisor in the plant.

.-J3L,

'

EX-CIll-O hr PRECISION

w

INDEX

Section

Page

GENERAL DESCRIPTION

Work Drive

............................................

............................

Grinding Spindle Drive and Helix Setting
Grinding Wheel Feed
Wheel Dressers

Lead Changes
Lead Control
Lead Pick-up

......................

...............................................

...............................................

Backlash Compensator

.................................

..........................................

.........................

...............................

Taper Threads .............................................

Tolerances

..................................................

Specifications .............................................

Machines Equipped for Operation . . . .

INSTALLATION

Foundation ...............................................

Leveling

Base Assembly .......................................

Connecting the Hydraulic Unit

Machine Table

Floor Plan Style 35 Thread Grinder .

Floor Plan Style 35-L Thread Grinder
Installing Lead Screw
Wheel Slide Assembly
The Wheel Feed Screw

Filling the Hydraulic System
Electric Connections
Starting the Hydraulic System

Connecting the Coolant Pump

Filling the Coolant Tank

....................................................

..............

..........................................

............................

............................

.........................

.................

...............................

..............

..............

.......................

.. •

100

102
103
103

104
104

104
104

104
104

104
105
106

200

201

201
201

201
201
202
203
204

205

206
207

208
208

208
208

LUBRICATION

Lubricating Pump

...........

Machine Lubrication . . .

Dresser Lubrication . . .

Spindle Oil Specifications

OPERATING INSTRUCTIONS

Table Controls

...................

Wheel Feed ......................

Automatic Cycle

.................

Dresser Feed and Start . .
Helix Setting

......................

Backlash Compensator . . .
Lead Control

......................

Taper Threads ...................

Lead Pick-up ...................

300

301
301
302

302

400

401
403
403

404

405
405
405

406

406

INDEX (Cont'd.)

Section

Page

Positioning the Work Spindle
Hydraulic Work Spindle Drive
Work Spindle Speeds
Mounting Dimensions

..........................................

..........................................

............................

.........................

Wheel Spindle Speeds .......................................

Tailstock
Lead Change .

................................................................

.......................................................

Determining Change Gears for Special Leads

Changing Wheel Pulleys

Mounting Grinding

Wheels

Summarized Setting Instructions

....................................

...............................

....................

MAINTENANCE...................

Cleaning the Coolant Tank

Hydraulic Oil
Hydraulic System
Grinding Spindle Service
Care of Grinding Wheels

...................

.............

Electrical Maintenance . .

HYDRAULIC MACHINE ACTUATION

.................

Pump Pressure and Pump Control Pressure

Accessory Pressure .....................

.............

Panel Pressure ..........................................

Motor Control

Pump Delivery Control
Manual Direction, Start and Stop Control . .

Automatic Stopping and Starting ....................

Stop

and Dress Control

Hydraulic Service
Schematic Hydraulic Diagram

.....................................................

.....................................

....................................

...............................................

.........................

406
406

407
408
409
409

410
418

421
421
422

500

501
501

501
502

502

502

600

602
602
602

602
602
603
603
603

603
605

DRESSERS, ATTACHMENTS AND EQUIPMENT . . .

Three Way, 60° and 29° Form Dresser .................

Three Way, Plate-Type 10° to 90° Form Dresser
Three Way, Cradle-Type 10° to 90° Form Dresser

Universal Cam-Type Dresser ..................................

Internal Straight Line Dresser

Internal Pantograph-Type Dresser

Internal Thread Grinding Attachment

Wheel Thinning Attachment .......................................

Oil Cooling Unit

Suction Hood

.............................................................

...................................................................

Relieving Attachment, Table-Type
Relieving Attachment, Spindle-Type

Quick-Clamp Type Index Head .................................

Table Extension with Tailstock

Cam Grinder for Universal Dresser Cams

..................................

............................

......................

............................

......................

.................................

...........

700

701

.

702

702

703
704
705

706
708
708

709
709
713
714
714
714

INDEX (Cont’d.)

Section

Page

Grinding Wheel Balancing Stand
Headstock Center Grinding Attachment

...........

Bench Type Lead Pick-Up Fixture . .

Center Lapping Machine ......................

Other Attachments and Equipment . . .

UNIVERSAL CAM-TYPE DRESSER

General Description
Lubrication

................................................................

...............................................

Changing Cams .......................................................

Adjusting or Replacing Diamonds ......................

Thread Form Corrections

Care of Diamonds

.....................................................

Diamond Specifications
Diamond Drawings

.....................................................

....................................

..........................................

Setting Fixture for Universal Dresser Diamonds

THREAD GRINDING AND GRINDING WHEELS

Grinding
Wheel Speed
Work Speeds
Coolant

Wheels

...............................................

...........

............................................

.....................................................

................................................................

Dressing and Dressing Diamonds ..............

Depth of Grinding Cuts .................................

Balancing Grinding Wheels

............................

Long, Thin, Precision Threaded Parts . . .

Work Centers ..................................................

Work Drive Dogs
Steady Rest
Material

.......................................................

.............................................................

Grinding Suggestions

Correcting Unsatisfactory Grinding

............................................

.......................................

...........

Thread Grinding Wheel Recommendations .

Grinding Wheel Speed Charts
Work Speed Charts

715
715

715
716

716

800

l

4

5
6
7

8

8

9

10

900

901
901

901
901
902

902
903
903

903

903
903
903

904
904
904

REPLACEMENT PARTS

1000

GENERAL DESCRIPTION

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

FRONT VIEW OF STYLE 35 THREAD GRINDER

1

Work head housing, containing lead change
gears and work spindle drive

2 Rapid traverse speed control lever
3 Work spindle

4 Coolant control valve

5 Wheel slide cradle
6 Machine table control dogs
7 Machine table start and stop lever

8 Lead controls
9 Grinding wheel

10 Taper setting adjustments

11 Tailstock
12 Lead pick-up controls
13 Backlash compensator
14 Machine table
15 Electric push buttons
16 Work spindle direction control
17 Machine table manual reversing

control
18 Machine table speed control orifices
19 Manual dresser start and feed lever
20 Size setting controls

101

GENERAL DESCRIPTION

REAR VIEW OF STYLE 35 THREAD GRINDER

21 Wheel drive motor
22 Lights, indicating operation of dresser
23 Guard over grinding wheel and dresser
24 Helix setting hand wheel
25 Dresser motor

The Ex-Cell-O Styles 35 and 35-L Univer
sal Precis ion Thread Grinders are identical in
operation. The installation, operation and
maintenance instructions in this book apply
to both machines.

The

machines maybe operated either manu
ally or fully automatically except for starting
the cycle, starting after dressing, unloading,
loading and resetting the grinding wheel.

WORK DRIVE: The work spindle is worm
driven through a V-Belt and two three-step
pulleys from a variable speed hydraulic motor.
This motor, mounted in the work head housing,
provides an unusually wide range of work

26 Coolant pump motor
27 Dresser control buttons
28 Guard over main drive motor, ,

hydraulic pump and filter

29 Coolant oil tank



speeds, all controlled from the front of the
machine.

The machine table, with the work spindle
and adjustable tailstock, is moved on anti
friction ground and lapped
and ground lead screw. The lead screw is



mounted with the nut under the table and driven

by a train of gears from the work spindle.

rollers

by

By means of adjustable dogs any arrange
ment between rapid and feed movement, to suit
the individual workpiece, is
No

special cams or inserts are necessary. The
adjustable table dogs contact valve plungers
controlling the direction of table travel, the

instantly

length of the rapid and grinding strokes and,

a

hardened

available.





102

GENERAL DESCRIPTION

during single or two pass grinding, the auto
matic stop.

The table cycle is started with a hand

lever. Three hydraulic orifices control the

rate of work speed and table travel. A manual

table reversing knob is also provided.

GRINDING SPINDLE DRIVE AND HELIX
SETTING: The grinding spindle is driven
through a V-belt and two-step interchangeable
pulleys. The driving motor is mounted directly
behind the grinding spindle. The mounting is
adjustable to maintain proper belt tension.



The spindle and drive motor are retained
in a cradle on the wheel slide. The cradle is
tilted to the desired helix setting. The adjust

ment is made with a hand wheel. Graduations

on the cradle and on the hand wheel simplify
the adjustment.

GRINDING WHEEL FEED: Manual or auto

matic feed is available with the feed hand wheel

with ratchet pawl. The wheel slide is auto

matically moved toward the work the amount

dressed off the wheel during the

dressing cycle.






FRONT VIEW OF STYLE 35-L THREAD GRINDER

1 Work head housing, containing lead change

gears and work spindle drive

2 Rapid traverse speed control lever
3 Work spindle

4 Coolant control valve

5 Wheel slide cradle
6 Machine table control dogs
7 Machine table start and stop lever

8 Lead controls
9 Grinding wheel

10 Taper setting adjustments

11 Tailstock
12 Lead pick-up controls
13 Backlash compensator
14 Machine table

15 Electric push buttons
16 Work spindle direction control
17 Machine table manual reversing

control
18 Machine table speed control orifices
19 Manual dresser start and feed lever

20 Size setting controls

103

GENERAL DESCRIPTION

Therefore no dresser compensation is neces
sary except for diamond wear.

WHEEL DRESSERS: Four types of grind
ing wheel dressers are available with these
machines. They are described in detail in the
700 section of this book.

The grinding wheel may be dressed auto
matically either before or after the finish cut.
Manual dressing control is available with a
hand lever which feeds the dresser and starts
the operating cycle. After the dresser is

started it automatically completes one cycle
and stops. Pilot lights indicate the operation
of the dresser.

The dresser is mounted directly behind the

grinding wheel and is driven by an electric
motor. The power operated dresser feed may
be disconnected and

the dresser slide operated
manually. For operation while the dresser is
being set to a new grinding wheel, an electric
push button is provided at the side of the base
below the slide.

LEAD CHANGES: The various pitches are
produced with change gears. A set of change
gears for most standard pitches is furnished
with the machine.



THE BACKLASH COMPENSATOR is auto

matically actuated in conjunction with the lead

screw, making it possible to grind in both di



rections of table travel. The direction of travel
can be reversed with the wheel in the cut. It

is not necessary to have an undercut at the end

of the thread or to run the wheel off the work

before reversing.



TAPER- THREADS: For grinding taper
threads the upper part of the machine table
containing the headstock assembly and support
ing the tailstock assembly is swiveled to an
angular position. The change in lead caused
by the setting is corrected with the suitably
graduated lead control.

TOLERANCES:
Form and similar threads a tolerance on the
pitch diameter of plus or minus .0002 M can be
held with manual operation and plus or minus
.0003

” with automatic stop and dress control.
Lead can be held on any thread form to plus
or minus .0002
.0005

” in any twelve inches.

” in any inch, and plus or minus

On American National






The machine is regularly equipped with a
master lead screw for American or British
leads. Metric lead threads can be ground with
this lead screw either by the use of a special
gear, which is available, or by altering the lead
obtained with the standard change gears by
means of the lead control. The machine can
also be furnished with a metric master lead
screw and metric wheel feed graduations.

LEAD CONTROL: The lead obtained with
the change gears may be lengthened or short
ened. This feature makes it possible to grind
odd. leads and to hold accurate overall lead
dimensions.

LEAD PICK-UP: The lead pick-up device
provides a means of moving the table without
turning the work spindle so that pre-cut threads
may be matched with the grinding wheel.



THE HAND WHEEL ASSEMBLY CONTROLS

SIZE, WHEEL FEED AND AUTOMATIC STOP.

104

GENERAL DESCRIPTION

STYLES 35 AND 35-L PRECISION THREAD GRINDERS

Maximum diameter work ground with 18" wheel

Maximum diameter work ground with 14" wheel
♦Maximum diameter swing over table

....................................................................................

Maximum diameter work inserted through work spindle .

Grinding wheel size . . . .

.......................*............. 18" diameter, 9" hole, 3/8" and 1/2" thick

............

............

.................................................. 1-5/8"

Minimum grinding wheel diameter ....

Grinding wheel speeds ............................

Grinding wheel motor

Main driving motor .........................

...............................

* • *

Work spindle speeds, grinding ..............

Work spindle speeds, rapid traverse . .

Maximum helix setting of wheel ...........

Coolant tank capacity .................

Coolant pump capacity

...............................

..

Coolant motor ..........................................

Hydraulic reservoir capacity

.................

1485, 1575, 1670, 1780, 1910, 2040, 2150, 2290,
.

..................................

.

............................................ 3 hp, 1200 rpm

.

................................................. 2 to 160 rpm

................................................. 2 to 250 rpm

.......................................... 45° left hand threads

...................................................................... 50 gal

...................................................................... 18 gpm

.................................................. 3/4 hp, 3600 rpm

...................................................................

Overall height ..........................................

Overall height with fan-type suction hood
Base dimensions at floor

.........................

INTERNAL THREADS

Maximum inside diameter of work ...........

. . . . ;

...................

Maximum length of internal thread .............................................

Minimum inside diameter of work ...........................................

Maximum length of internal thread on minimum (1") diameter

14-3/4"

2450, and 2640 rpm

30° right hand threads

3 hp, 1800 rpm

75" wide, 60" deep

8"

12"

13"

22 gal

59"

72"

8"

3"

1"
1"

STYLE 35 ONLY

EXTERNAL THREADS
Maximum work length between centers

..................................

Maximum threaded portion of work, from headstock center

Maximum lead control, plus or minus per foot .................

Maximum taper per foot ...........................................................

Floor space required for table travel
Net weight of machine (approx.)

................................................

.....................................

Weight of machine crated for domestic shipment (approx.)

Weight of machine boxed for export (approx.)

Size of box for export (approx.)

................................................

STYLE

......................

35-L ONLY

EXTERNAL THREADS

Maximum

work

length between centers

..................................

Maximum threaded portion of work, from headstock center
Maximum lead control, plus or minus per foot

....................

Maximum taper per foot .....................................................

Floor space required for table travel

.....................................

Net weight of machine (approx.) .............................................

Weight of machine crated for domestic shipment (approx.)
Weight of machine boxed for export (approx.)

.......................

Size of box for export (approx.) .............................................

♦Information on 19" and 24" swing available on request.

33"
22"

040"

2"

. . . 124"
. 9200 lb

10,500 lb
11,400 lb

290 cu ft

, . 48"

36"

.025"

..

1-1/2"

153"

9800 lb
11,200 lb
12,300 lb

360 cu ft

105

GENERAL DESCRIPTION

STYLES 35 AND 35-L THREAD GRINDERS SUITABLY EQUIPPED FOR OPERATION

V/f

O Double wheel setup for grinding threads

and removing incomplete thread on propeller
shaft. One wheel is shaped to grind the thread
form, the other is dressed flat to remove the
first incomplete thread. Both wheels are
mounted on

one

adapter with a spacer between.
One dresser shapes both wheels. A nut arbor
is used to hold the part. Approximate locators
facilitate loading and unloading.

O The index head positions the work for each

start of the quadruple Acme form thread. A
steadyrest prevents deflection. The pre-cut

thread is positioned with the machine mounted
lead pick-up device. A live tailstock engages
the large center in the work. The work is
maintained near room temperature with an
extra stream of coolant from the refrigerator

type oil cooling unit.

A drawbar through the work spindle is used
with a U-washer to hold this aircraft crank
shaft at the headstock end. Approximate loca
tors aid in handling the part. The suction hood
prevents vapor accumulations around the ma
chine. Extra coolant is supplied to the point

on the wheel.

O The table extension is required for handling
the long part described above. A live tailstock

center is used because of the large area of
contact with the work.







106

INSTALLATION

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

When the machine is uncrated all parts
should be checked against the shipping list to
be sure that the complete shipment is received.
Smaller boxes and packages inside the large
boxes contain parts.

The machine should

be

thoroughly inspected
to be sure that no part has been damaged during
shipment. The paper wrappings used as pro

tection from dust and dirt should be removed.
The wooden skids should be left on the base
until the machine is in place.

In the desired location, sufficient space
should be allowed for efficient operation and
cleaning the coolant tank. A clearance of four
or five feet is suggested. When a crane is
used to lift the machine into position the rope
or cable must not bind any part where it might
cause damage. No force should be exerted on
the

spindles

that might injure the

precision ball

bearing races.

The grease and rust preventive should be

removed with clean kerosene and clean cloths.

Waste should not be used because it leaves

lint. A brush with stiff bristles can be used to

clean in the corners. An air hose should not
be used because it may drive grit into the

bearing surfaces.

FOUNDATION: For satisfactory perform

ance the thread grinder must have a solid,
level foundation. A concrete floor is best, but
a firm wooden floor free from vibration will
do. When the machine is placed on an upper

floor or balcony it must be placed as close as

possible to a pillar or column of the building.

LEVELING: Three rest pads and boltholes
are provided in the base. This three-point
bearing assures a solid footing and facilitates

leveling. A good level should be placed on the

flat table way to level the machine lengthwise,

and on the flat wheel slide way to level the

ma-

chine crosswise. Adjusting blocks or steel
shims should be used under the rest pads.

When an assembled machine is moved to a
new location, it can be leveled by swiveling the
upper part of the machine table (Instructions
on how to swivel the table are given on page
406 under “

Taper Threads”) and placing the
level on the exposed flat surface. The as
sembled machine can be leveled crosswise by

placing the level on the rim of the coolant



trough at the right of the machine base behind

the electric

at this point is machined parallel to the wheel

control

cabinet. The coolant trough

slide ways.

BASE ASSEMBLY: The machine is

partially disassembled into three major units:

the base, the wheel slide and the work table.
The largest crate contains the machine base,
the lead screw, the cross feed screw and other

parts. The long narrow crate contains the work

table, and the smallest crate contains the wheel
slide.

The largest crate containing the base should

be opened first All the parts should be thor

oughly cleaned with kerosene and clean cloths.
All tape and rust preventive
After the table ways are thoroughly cleaned
two 1/8" pipe plugs must be removed. These
plugs are near the center of the ways. They

should be removed.

serve to keep dirt out of the lubricating lines
until the machine is assembled.



CONNECTING THE HYDRAULIC UNIT:
The hydraulic unit, consisting of the pump, the
electric motor and the filter, is placed in the

drip pan, then moved close to, but not touch

ing, the machine base at the left rear. There

are three connections to be made. The large
flexible hose connects the pump to the hydraulic
sump in the machine base; the smaller hose
from the machine base is connected to the
filter; the small coil of metal tubing goes from
the pump to a fitting in the base.

MACHINE TABLE: The machine table

should be uncrated and

thoroughly cleaned next.

There are two roller bearing cages for the

shipped







201

'

INSTALLATION

i

51 -

2

43

45 —

4

OIL COOLING UNIT —

(OPTIONAL EQUIPMENT)

STANDARD

COOLANT TANK

OUTLINE OF BASE

AT FLOOR

r'

\

N'

\r_2_

L-CP

*\

n

96

60 --

" ■>

88

1

8

SF

<3

>*

1

56 -

2

t

I
I

a

3F

V »

4

10 2

- DIA., 3 HOLES
8

31

124 EXTREME DIMENSION

FLOOR PLAN OF EX-CELL-0 STYLE 35 THREAD GRINDER

V-way, and two for the flat way. The long
cages are for the table ways. The short V-cage
and flat cage are for the wheel slide ways.
The respective cages should be interlocked by
inserting the hooked tongue on the end of one
into the slot of the other. The cages should be
placed on the ways so that they are in the ap
proximate center of work table travel. The
ways should be well oiled.

202

71

1

2

r

— ll

4

75

The

lead control sine bar at the front of the

table should be at the zero position in relation

to the reference line on the edge of the sight
hole. Two knurled knobs on the front plate
control the movement. The one toward the
right locks the adjustment, the one at the left



actuates the bar.

The sine bar follower arm in the base

should be pushed toward the back so that it

INSTALLATION

does not interfere when the table is placed on
the ways. When the machine is started the

follower will be brought into position by hy

draulic pressure.

The machine table can be lifted in a level
plane as follows: A hardwood roller or piece
of 4

"

x 4 ”

wood is inserted in the round open

ing in the right end of the work table and left

45 —

OIL COOLING UN'T -

(OPTIONAL EQUIPMENT)

STANDARD

COOLANT TANK

protruding ten or twelve inches,
plate is removed from the upper rear of the
work head, the door in the front of the work



head is opened, and the rope or cable slipped

through the opening beside the hydraulic work

drive motor. With the rope through the work
head at the left end, and around the roller or



piece of 4"x4" wood at the other end the table
can be lifted safely.

1

51-

2

43-

4

The cover

( '

OUTLINE OF BASE

AT FLOOR

-DIA., 3 HOLES
8

45

J -.j.

/

D

J/

/_

_

1

56-

2

60-

@4?

V

\

153 EXTREME DIMENSION

- 71 “

75

1

2

□

-m

I

4-

i

2

— 1 —

10

i

4

96

88

1

8

\

FLOOR PLAN OF EX-CELL-0 STYLE 35-L THREAD GRINDER

203

INSTALLATION

THE FLEXIBLE HYDRAULIC LINES TO THE
TABLE:
three toward the center. These hose
connections are to be made after the

three at the left end, and

table is placed on the ways..

An alternate method of lifting the table is

to insert an S-hook into the hole at the right

end of the table and fasten a C-clamp toward
the rear of the top wall in the change gear
compartment. If this method is used care must

be taken that the small lubricating line in the

gear compartment is not injured.

The machine tables weigh between 3,500
and 4,000 pounds, so the ropes or cables must
be sufficiently strong. The crane or chain

falls used in assembling the machine must be
smooth running. The table should be lowered

gently and in a level plane. It should be placed

on

the ways in such a relation to the base that

the roller bearing cages

remain

in

the approxi

mate center of table travel.

There are six flexible hydraulic lines to be
connected with the base and the table. Three
flexible lines run from under the left end of the
table to fittings in the left end of the base.
These three lines run parallel so individual
markings are not necessary.

Three

connections are to be made from
lines under the table to a manifold bracket in
side the base near the center of the machine.

/‘~v

■,

r'

f

INSTALLING THE LEAD SCREW

A Gear rack guide
B Gear racks
C Hydraulic fittings in backlash

compensator.

D Cover plate, from end of the

table

E Rack cover plate

These connections can be made through a cored
opening in the rear of the base above the hy
draulic pump unit. These lines also run

F Lead screw
G Wood half-bearing

H Flexible hydraulic lines

parallel.



When any flexible hose is connected it
should not be twisted. The hose bends
but bending while it is twisted shortens the
service life.

INSTALLING LEAD SCREW: Before the
lead screw is installed, two gear racks B in
the lead pick-up device must be removed. To

do this it is necessary to place the hand crank

on the shaft K, (shown in drawing) push the
knurled knob L toward the table and turn the
crank counterclockwise enough to free the
assembly. Then, after taking the round cover

plate D off of the right end of the table, (as

seen from the front) and removing the rack
cover E inside this opening, the rack guide A
and the gear racks B can be taken out This



allows the pinion gears shown in the drawing
to rotate independently.

readily,



204

INSTALLATION

B

.

/

>
—

/

/

J§P

Trn.

—

I

xj

4

3

BACKLASH

COMPENSATOR

CYLINDER

A

r

The gear racks B are then dropped in place.
It may be necessary to move the table slightly
until the racks can drop into position. The
pinions rotate in needle bearings. If the pinions

are lifted, care should be taken to avoid drop

ping the bearings.

The hand crank is placed on shaft K. The
gears are disengaged by pushing knob L toward

the rear. Shaft K is turned clockwise until, by
the action of the screw which is operated by



shaft K, all the end play is removed. The knob

L is released and the gears are allowed to

engage at a position where the assembly is

sufficiently free so that shaft K can be rotated

with the hand crank without binding and without

end play.

The rack guide and cover are then replaced.

The cover over the round opening in the end of

the table can then be assembled.

The backlash compensator must be con

\

nected to three flexible hydraulic lines H under

the

table.

are also numbered to correspond with the fit

:::

tings C on the backlash compensator so that

f

These lines are different lengths and





correct connections are assured.

TABLE

-

BRACKET

BACKLASH COMPENSATOR AND LEAD

12

32

PICK-UP DEVICE

A flanged wooden half-bearing G is provided

to slip into the lead screw support bracket at

’

the right end of the work table so that the lead

screw will slide through without injury. This
half-bearing can be discarded after assembly.

The lead screw should be cleaned, dried
thoroughly and covered with a thin film of light
oil. With the wooden half-bearing in place in
the bracket, the lead screw is slipped through
until it enters the threaded nut. It is then
turned into position by hand as far as possible.
The table should be pushed lightly to the right
until the splined end of the lead screw engages
the driving member.

The backlash compensator cylinder is

placed at a distance of 13/32

” from the table

bracket. The end of the screw controlling the

left rack must be at the scribed line M. This

is done by turning the knurled knob L.

WHEEL SLIDE ASSEMBLY: The roller

bearing cages should be

placed

in

the approxi

mate center of the wheel slide ways. For these

ways there is one V-cage and one flat cage.

The ways should be well oiled.

The wheel slide should be uncrated and

thoroughly cleaned. Rust preventive and tape

best be removed from the ways, oil lines,

can
feed screw nut and bracket while the slide is

lifted by a crane. The slide must be placed on
the ways gently, and in a level plane. This
prevents the rollers from marring the ways.
The wheel slide is best lifted by inserting the

rope or

with the cradle rotated to 15° as indicated on

the helix angle scale, the slide ways will be
level.

cable through the belt chamber. Then

There are four hydraulic connections to be
made between the wheel slide and fittings in
the base. To make these connections it is

necessary

opening in the rear of the base. The lines on

the wheel slide and the fittings on the base

for the fitter to enter the cored

have numbered tags attached. The lines are



205

INSTALLATION

■

I

fflBii

*smp**«*v:**i

i

”

rr*

' ' 7

!

3

BA

J* z

WHEEL FEED SCREW ASSEMBLY

simply connected to the fittings with corre
sponding numbers.

To install the wheeLspindle, the sheet metal

side guard at the left of the cast wheel guard

(as seen from the front of the machine) and the
sheet metal cover plate at the front of the
wheel spindle support bracket must be re

moved. Behind the front cover plate there are

four set screws which must be loosened, and a

hexagon head spindle adjusting screw which,

with its threaded collar, must be removed.

Then the spindle can be slipped into the sleeve

from the left end, and the spindle adjusting

screw and collar replaced. This eccentric
adjusting screw serves to move the spindle

endwise to obtain the correct position of the

•' ~ ' ^

grinding wheel in relation to the dresser. Then



the four set screws are tightened, locking the

spindle in position. The front cover plate can



be assembled. The grinding wheel should

now
be mounted as explained on page 421, and the

sheet metal side guard replaced.

The pulleys and belt can now be mounted

Instructions on mounting pulleys are on page

421. The correct pulleys to use for the desired
wheel speeds are given on page 409.

THE WHEEL FEED SCREWshould be thor

oughly
then light oil applied. The feed panel must be
disassembled before the cross feed screw can
be installed.

cleaned with kerosene and a clean cloth,

- •

’ ~i .':**!



206

INSTALLATION

P-

THRUST BEARINGS

/,' / y

/ / y

y / / / / /

\^

m

%C

Li

WHEEL FEED SCREW ASSEMBLY

The feed control bracket V is removed by
loosening the four mounting screws,
pinion cover plate X is then removed. The
nut BE and the washer are taken off to remove
the cross slide hand wheel assembly BF. Be
hind the hand wheel is a retainer ring posi
tioned by pins and holding four springs. The
ring and the springs need not be removed.
The rack actuating lever BCand the pipe plug,

spring and spring cup BD which are in the right

rack shaft bracket, are disassembled. The
dresser valve pinion gear W can be removed
by inserting a 1/4-20 screw in the tapped hole
at the end of the pinion. The rack shaft S
should be moved

to the right until it clears the

left bracket. The bronze feed arm BB can be
removed by driving out the taper pin BA and

removing the shoulder screw Z. To remove

the panel R the four socket head screws are
taken out. The two draw screws T can be
tightened until panel slides out freely. The
draw screws T should be backed out so panel

will be ready for re-assembly.

The inner panel P is removed by taking out
the nine socket screws around the edge of the
plate, the one larger screw between the two

openings, and disconnecting the three hydraulic

The

lines from the feed cylinder. This panel

then be removed carefully.

u

The feed screw Q is then inserted through

the clearance holes in the base and screwed

into the bronze nut in the cross slide. One of
the thrust bearings, composed of two washers
and the bearing, should be

slipped on the outer
end of the feed screw, the panel P replaced,
and the hydraulic lines to the feed cylinder
connected,

The drawing shows the correct

assembly of the bearings.

The second thrust bearing, the key and the

cross feed gearU are placed on the feed screw.

This gear has 70 teeth. The two lock nuts Y
are assembled and tightened. The feed screw

Y

Q must rotate freely and without end play. For

checking the end play an indicator is placed
against the end of the shaft and the shaft rocked
back and forth by hand. The panel R is then

replaced and the socket head screws tightened

evenly.

The bronze feed arm BB is slipped onto
the feed cylinder shaft BG and secured with
the taper pin BA and screw Z. The feed control
bracket can then be mounted.




The pinion gear W and the rack shaft S are

inserted into the bores. At the

end

ment to the left, the rack shaft S should extend
almost 1/8" beyond the bracket at the left end.
To obtain this, the tooth engagement may be
changed by removing the pinion gear W, moving

the rack shaft S and re-inserting the pinion
gear W until the proper position is obtained.

The right rack shaft bracket is assembled by

placing the rack actuating lever BC so that its

gear

meshes

with the rack shaft when the lever

is against the stop pin. The spring cup, spring
and pipe plug BD are assembled next.

The cross

slide

hand wheel BF, the washer

and the nut BE are then replaced. The hand
wheel should be checked to be sure that the

roller on the actuating lever BC rides up on
the cam freely without binding. It may be

necessary to change the tooth engagement of

one of the two pinions to obtain this.

FILLING THE HYDRAULIC SYSTEM: The
filler opening for hydraulic oil is at the left
end of the base. The reservoir should be
filled within about one inch of the opening. A

of

the move

can



207

INSTALLATION

rod on the filler cap is inscribed “H” and
to show the oil level. About twenty gallons of
hydraulic oil is required.

ELECTRIC CONNECTIONS: The pov/er

line connection to the control cabinet is made

first. The dresser switch must be set to the

“

off

” position. The hydraulic pump motor is

then connected to the machine with the attach

ment plug and receptacle. This motor should

rotate in the direction indicated by the arrow
on the hydraulic pump. The start and stop push
buttons on the electric panel should be jogged
until the direction of rotation can be seen. If
it is wrong, it will be necessary to reverse
any two of the line wires to the control cabinet.
When the hydraulic pump motor rotates in the
right direction, the rotation of the other

motors

will also be correct.

After it is determined that the hydraulic

pump rotation is correct, the wheel

and

dresser

motors can be connected. These connections
are made in the sheet metal box at the rear of
the machine base. The wires in the flexible
conduits

and

the wires in the box are numbered.
If the wires with corresponding numbers' are
connected, the direction of rotation of these

motors will be correct.

A receptacle in the box at the rear of the
machine is provided for connecting the coolant
pump. If a refrigeration type oil cooling unit
and a suction hood are ordered with the ma
chine, additional receptacles are provided in
this box for these accessories.

STARTING THE HYDRAULIC SYSTEM:
After the hydraulic reservoir is filled to the
proper level the system can be started by
jogging the start and stop push buttons several
times until the air is expelled from the pump

and it runs quietly. The pump should then be
allowed to run for ten or fifteen minutes until
the air is expelled from the entire system. All
visible connections should be checked for leaks.



The two direction dogs should be mounted
between the two safety dogs on the table of the
Style 35 machine, or between the stop screws
on the Style 35-L machine. The table start
and stop lever should be moved to the “

position, and the table allowed to reverse

rapidly for about ten minutes. When the table
operates smoothly all air has been expelled.

If the hydraulic pump is noisy and
oil is in the reservoir, the intake assembly
should be checked for air leaks.

CONNECTINGTHE COOLANT PUMP: The
coolant tank containing the motor-driven pump
should be placed at the rear of the machine

base. There are two hose connections to be

made: one at the grinding wheel guard and one

at the pump.

The coolant oil, after passing over the work
and the grinding wheel, drains from the table
into the trough of the machine base and returns

to the tank through a spout in the rear. A

system of baffles in the tank aid in settling the

grit from the oil.



FILLING THE COOLANT TANK: The
capacity of the coolant tank is fifty gallons.
This fills the tank to the top of the highest

baffle with the pump idle. This level should
always be maintained. It should be checked
daily and additional oil added as needed.

A good grade of thread grinding coolant oil
should always be used, as the nature of the

coolant has a decided influence on wheel life

and the results obtained by the machine.

Start

sufficient

”

208

LUBRICATION

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

LUBRICATION. The use of the specified

lubricants at the designated places is required
for the best operating performance. In the
Ex-Cell-O precision ball bearing spindles
special precautions must be taken to use the
specified lubricating oil, or an oil of equivalent

quality.

Different makes of oil, especially spindle

and hydraulic oils, should not be mixed. Some

oils are made from chemically different bases

which, when mixed, may be harmful to the

operating mechanism. If changing from one
make of oil to another is unavoidable, the sys

tem should be cleaned thoroughly.

Before the machine is started, the lubri
cating pump, the wheel spindle and the work
spindle reservoirs should be filled with oil.

THE LUBRICATING PUMP oil reservoir
holds about a quart of machine oil. It is pro
vided with a sight glass to show the oil level.

The oil pump in this res

ervoir is connected to

O-

OJii

<5L

lines which radiate to
all inaccessible parts of
the machine, such as the

cross slide ways, table

ways and lead screw.

m

i

i

. •

ground, the table reversals and the pumping

strokes are more frequent. A knurled knob,

shown in the photo, may be adjusted to length
en or shorten the pumping stroke and thus
supply more or less oil. On short work pieces
the knob may be turned to the right to restrict

the flow of oil, and on long threads it may be
desirable to turn the knob to the left for a
greater flow of oil. The flow of oil cannot be

stopped, but merely limited by the adjusting

knob.

:

The lubricating pump

* is automatically actuat-
i ed at each table reversal.

If a short work piece is

The proper oil level in the reservoir, as

shown in the sight glass, should be maintained.

MACHINE LUBRICATION

THE WHEEL SPINDLE is lubricated
through a well, covered by a knurled cap, on
top of the spindle housing. Spiral grooves on
the spindle shaft carry oil to the precision
bearings. A high grade spindle oil must be
used. (Spindle oil specifications are listed at
the end of this section).



When the machine is first operated, or after

it has been idle for some time, the spindle res

ervoir must be filled to make certain that the



bearings are thoroughly lubricated. When the
machine is used continuously this reservoir
should be filled about every four hours.



THE WORK HEAD SPIND LE BEARINGS are

lubricated through the reservoir covered by a

knurled cap at the back of the work drive hous

ing. This reservoir should be filled daily with



spindle oil.

THE WORKHEAD SPINDLE WORM DRIVE
lubricating plug is located at the rear of the

work head housing. It must be filled to the

level of the plug with a good grade of machine
oil when the machine

is first put into operation.

Thereafter, the overflow from the spindle bear

ings will maintain the correct level.



THE WORK HEAD GEAR TRAIN is lubri
cated automatically by a plunger pump, oper
ated by a cam from the work drive shaft. The
oil level is maintained by oil from the work
drive and spindle bearings.

THE IDLER PULLEY for maintaining belt
tension, located in the work head housing, has
a pressure fitting for ballbearing grease. This
should be lubricated every six months.

THE WHEEL HEAD FEED MECHANISM
AND DRESSER ACTUATING MECHANISM are
lubricated through ball-valve oilers located










301

lubrication

back of the cross feed hand wheel. A good
grade of machine oil should be used daily.

THE COOLANT PUMP MOTOR has an oil

at the side which requires machine oil

cup

weekly. The upper ball bearings have sealed-

in lubrication and require only a few drops of

oil once a year.

THE WHEEL DRIVE MOTOR AND THE
HYDRAULIC PUMP MOTOR should be lubri
cated with a good grade of ball bearing grease
every three to six months depending on the
extent the machine is used.

THE DRESSER MOTOR has a sealed-in

lifetime lubricating system that requires no

attention.

Any instructions that appear on plates or

tags attached to the motors should be followed.

RELIEVING ATTACHMENT, TABLE-

TYPE: The head-stock center bearings should
be oiled weekly with spindle oil through the
screw-plugged oiler. The camshaft bearings

require machine oil weekly through the screw-
plugged oiler at the opposite end. The sump

in the change gear compartment should be kept

sufficiently full of machine oil to lubricate the
gears.

DRESSER LUBRICATION

THE THREE WAY, 60° AND 29° FORM
DRESSER has four oil cups. The one on the
drive housing requires 600-W oil once a
month. The lever actuating slide should be
lubricated daily with machine oil through the
oil cup on the slide. The center arm pivoting
shaft should be lubricated daily with spindle

oil through the oil cup on the left side of the



arm. The dresser ways require daily lubri

cation with spindle oil through the oil cup on

the left side of the dresser base.

THE THREE WAY, PLATE TYPE 10° TO

90° FORM DRESSER has two oil cups. The

one on the drive housing requires 600-W oil
once a month. The lever actuating slide should

be lubricated daily with machine oil through
the oil cup on the slide.

THE THREE WAY, CRADLE TYPE 10° TO
90° FORM DRESSER has three oil cups. The
one on the drive housing requires 600-W oil
once a month. The lever actuating slide should
be lubricated daily with machine oil through
the oil cup on the slide. The dresser ways
require daily lubrication with spindle oil
through the oil cup on the left side of the

dresser base.



RELIEVING 1 ATTACHMENT, SPINDLE-
TYPE: Whenever the relieving attachment is
used, seven oilers, located at various points

in the relieving mechanism, should be oiled

daily with machine oil.

At the front of the wheel slide, just below
the spindle, is a small oiler. This lubricates
the gear shaft that connects the drag link oper
ating the eccentric sleeve on the wheel spindle.

Attached to the back of the work table, is

the. bracket that guides the shaft carrying the

roller.

An oiler is located in this guide

bracket.

At the gear drive, located on the work table

at the spindle drive, are five oilers that need
attention. One oiler is located at the top of the
housing, two at the front of the housing, and the

other two at the rear of the housing. These

five oilers lubricate the bearings of the shafts

in the gear housing.

302

THE UNIVERSAL, CAM-TYPE DRESSER

requires 600-W oil in the drive housing once a

month. This is applied through a pressure

fitting, on the housing. The driving mechanism

in the carriage should have 600-W oil every

other day. The oil cup for this mechanism is
accessible after the dresser cover is removed.
The cradle bosses on each side have screw-



plugged oil holes that require spindle oil once
a week. The dresser ways should be lubricated

daily with spindle oil through an oil cup on the

left side of the dresser base. The faces of the

cams should be kept greased.

SPINDLE OIL SPECIFICATIONS: Specific

gravity: .845; Beaume gravity: 35 minimum;
minimum flash: 31 OF; minimum fire:
Saybolt viscosity: 58 to 60 seconds at 100F;
color viscosity: 75 Lovibond or number 1

A.S.T.M. (Socony-Vacuum “

E

” oil or equivalent.)

Gargoyle Velocite

345F:

OPERATING INSTRUCTIONS

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

OPERATING CONTROLS

6 Table control dogs and plungers

7 Table start, stop lever

8 Lead controls
10 Taper adjustment controls
12 Lead pick-up controls
13 Backlash compensator adjustment

TABLE CONTROLS: For automatic
of the machine table,
of

the table engage plungers in the hydraulic
control panel. The setting of dogs determines
the length and the position of the table
ments, including the length of the grinding
stroke, and if desired, the length of the rapid
traverse movement and the stop position.

The control plungers and dogs are so ar

ranged that each dog engages only one plunger.
The two direction plungers, 6f and 6j on the
sides, extend the least amount out of the panel.

dogs mounted on the front

control

move

15 Electric pushbutton panel
16 Work spindle direction control
17 Manual table, direction control

18 Speed setting valves
19 Dresser start and feed lever

20 Wheel feed control assembly

The other three plungers are staggered, each
a small distance ahead of the other.





Solid table dogs operate the direction plung
ers. Depressing the right direction plunger
6j causes the table to move toward the right,
depressing the left direction plunger 6f causes

the table to move, toward the left.

START AND STOP: The work table is
started and can be stopped manually by the
lever 7. It can be stopped automatically either

by engaging plunger 6h or by the automatic

cycle control-



401

OPERATING INSTRUCTIONS

6 Table control dogs and plungers

a Left direction dog
b Stop dog
c Feed dog
d Rapid traverse dog
e Right direction dog
f Left direction plunger
g Feed plunger

h Stop plunger
i Rapid traverse plunger

j Right direction plunger

7 Table start, stop lever

15 Electric pushbutton panel

a Start wheel and coolant pump

DIRECTION: The direction can be con

trolled manually with the knob 17, It is con

trolled automatically by the engagement of the
table dogs with the direction plungers in the
control panel.

The spindle direction control valve 16 must

be set and locked according to the change gear

arrangement for'either right or left hand
threads. Instructions on the setting are fur
nished on the

instruction

plate below the valve,

FEED AND RAPID TRAVERSE: The se

lection of feed or rapid traverse is obtained

b Start hydraulic pump

c

Stop wheel and coolant pump

d Stop hydraulic pump

e Master stop

Work spindle direction control

16

Manual table direction control

17

Speed setting valves

18

a Controls table speed during feed to

right

b Controls table speed during rapid

traverse in both directions

c Controls table speed during feed to

left

Dresser start and feed lever

19



automatically by engaging plunger 6g or 6i,



The over-riding type of trip dog is used to
actuate the feed, the stop and the rapid traverse
plungers. These dogs depress the plungers

through a lever which is effective in one di

rection of table travel only. The levers are
raised over the plungers or over-ride in the
other direction. Thereby independent operating

cycles are obtained for each direction of table



travel. The over-riding dogs are effective in
either direction, according to the assembly of



the operating lever. The lever is assembled
to the dog with a pressed-in pin.



402

OPERATING INSTRUCTIONS

When only a feed movement of the machine
table is required, without rapid traverse, the
feed and rapid traverse dogs are removed and
the feed plunger 6g is depressed.

The grinder must always be operated with
the direction dogs on the machine table. They
must never be moved past the safety dogs
the Style 35 grinder, nor past the set screws
on the Style 35-L,

WHEEL FEED: The positioning of the
grinding wheel and the feed movement is con
trolled from hand wheel 20a. For manual
operation the ratchet pawl 20b is disengaged.
With the pawl thus positioned all feed move

ments can be manually controlled.

When the power operated feed pawl 20b is

engaged with the ratchet gear, the wheel feed

is automatic at each table reversal. The

amount of feed is adjusted by turning knob 20i.

This knob can be turned only while the machine

is reversing. Turning the knob clockwise in
creases the feed; counterclockwise decreases

it.

There are two sets of graduations on the
feed hand wheel assembly 20. One set 20d is
integral with the hand wheel and cannot be ad
justed. The other set of graduations is on the
collar 20e. This collar can be rotated and

locked with screw-20c in any desired position.
The graduations on the collar indicate the set
ting of the hand wheel in relation to the cycle

stop position, or the finish size setting. The

ratchet disengaging shield, which prevents any

feed after size is reached, is part of this collar.

AUTOMATIC CYCLE: Two kinds of auto

matic cycles are obtainable. These are with

and without automatic wheel dressing.

AUTOMATIC CYCLE WITHOUT WHEEL
DRESSING: The machine is set by positioning
the stop dog or dogs and adjusting the wheel
feed. For single pass grinding two stop dogs
are used, one at each end of table travel. For
two pass grinding one stop dog is placed at

whichever end it is desired to stop the ma
chine table.

on





20 Wheel feed control assembly



a Hand wheel
b Ratchet pawl

v._;

____

c Screw to lock graduated collar

d Graduations on handwheel





e Graduated adjustable collar
f Pointer
g Stop and dress cam
h Cam roller
i Feed control knob

AUTOMATIC GRINDING WITH WHEEL

DRESSING:

The machine will automatically

take a number of cuts of pre-determined depth

and then stop and dress the wheel either before
or after the finish cut. If the wheel is dressed

before the finish cut the table is restarted

manually, the finish cut is taken and the table
stops. An attachment to automatically start



the machine for the finish cut after dressing is
available as extra standard equipment.

With the machine set for automatic grind

ing with dressing, the operator must reset the
wheel 20a at the end of the grinding cut, unload
the work, load a new work piece and shift the

table start lever.



The first step in setting the automatic cycle
is to determine the final size setting. This is
done by grinding the first work piece manually
until the exact finish size is reached. At the



403

OPERATING INSTRUCTIONS

finish size position of the hand wheel the gradu

ated collar 20e is adjusted so that the stationary

pointer 20f is at the zero graduation.

The total amount to be removed is deter
mined next. This can be done by loading the
next work piece, and turning the hand wheel
until the point of the grinding wheel contacts
the outside of the work. The graduations on
the collar 20e indicate the amount of stock to

be removed.

From the total amount, the stock removed

the finish cut and on the initial cut are sub

on

tracted. The balance is divided by the number

of cuts. The result indicates the depth of each
roughing cut. In order to have the table stop
at the same end each time for loading and un
loading, it is necessary to take an even number

of cuts. -

Recommendations for the amount of stock
removed at each roughing cut and at the finish
cut are given in the ‘

'900 section

” under “

Depth
of Grinding Cut”. The initial cutis preferably
somewhat deeper than the other roughing cuts.

After the depth of a roughing cut is decided
on, the wheel feed is adjusted. Information on
this setting is included under “

Wheel Feed

on page 403.

If

the wheel is to be dressed before the

finish cut is taken, the stop and dress cam 20g

must be set so that the cam roller 20h will
ride up on the cam during the last roughing cut

feed.









21 Dresser feed hand wheel assembly

a Knurled knob to lock shield
b Graduated shield
c Hand wheel

”

d Knurled knob to position shield

dresser can be fed toward the wheel manually

by

the hand wheel 21c at the side

of the machine
below the dresser. The dresser cycle is started
from the side of the machine by pressing the
start dresser button.

If the wheel is to be dressed after the finish
cut during unloading, the stop “
20g

is

set so the cam roller 20hwill ride up on

and dress cam

the cam during the finishing cut feed.

The

depth of the power operated dresser
feed, obtained either during the automatic cycle
or by shifting lever 19, is adjusted by position

ing shield 21b. The setting is facilitated by

the graduations on the shield. The shield is

locked with knob 21a.

DRESSER

FEED AND START: The dresser
is started and fed toward the wheel either
manually or automatically as described under
automatic cycle.

The manual start dresser lever 19 at the
front of the machine, feeds the dresser toward
the wheel and starts its operating cycle. The

404



HELIX SETTING HAND WHEEL with grad

uations behind handwheel and on

wheel siide cradle



OPERATING INSTRUCTIONS

HELIX SETTING: The hand wheel at the
right rear of the machine is used to pivot the
cradle in the wheel slide to the required helix
angle. A pointer indicates the setting on a
graduated plate at the rear of the cross slide
cradle. Fine graduations on the hand wheel
assembly permit accurate positioning. Before
the adjustment is made two screws near the
pointer and three on the segment strip at the
front of the cradle must be loosened. The
screws must be tightened securely when the
setting is complete.

BACKLASH COMPENSATOR: The hydrau
lically operated backlash compensator auto
matically moves the

table

the amount required

to compensate for the backlash of the gears
and lead screw.

The backlash compensator must be adjusted
after each alteration of the change gears. The
adjustment is made with the knurled knob 13 on
the end of the compensator cylinder under the
right end of the table. Graduations facilitate
the adjustment. Each graduation represents

.00025" table movement.

The

correct setting of the compensator is

obtained as follows:

A grinding cut is taken

with the table traveling from left to right. The

table is then stopped. The graduation on the
hand wheel collar is noted in reference to the
pointer, then the wheel is backed away and the

i'

U

M?

f a.

(.- -r




W'

: 1

i

BACKLASH COMPENSATOR WITH ADJUSTING

l

...

.

KNOB AN-D GRADUATIONS

table reversed. With the coolant valve closed
so that sparks are readily noticeable, the wheel
is brought forward and the compensator ad
justed until, with the least amount of sparking,

. Ti v

■V-

f

v

the original setting of the hand wheel is
This indicates that the grinding wheel is
turning in exactly the same path it traveled on
the previous stroke.

LEAD CONTROL: At 8c is a sight hole
with two reference lines on the beveled edge,
one above and one below. Behind this sight

reached.

re-

!



8 Lead controls

a Adjusting knob

b Locking knob

c Sight hole

10 Taper adjustment controls

a Actuating knob

b Locking screw

c Graduations

12 Lead pick-up controls

a Screw shaft

13 Backlash compensator adjustment

405

OPERATING INSTRUCTIONS

hole is a sliding bar with two sets of gradu

ations, also one above and one below. At both

sides of the central zero position the upper
section is graduated in increments of .005".

At the central zero position of the sliding

bar the machine will grind the lead as deter

mined by the change gear setting. The lead is
lengthened by shifting the bar to the left. It is

shortened by shifting the bar to the right.

To move the graduated bar it is necessary
to shut off the hydraulic pump and loosen the
knurled knob 8b. The bar can then be moved
by turning knob 8a, After the bar is in the

desired position of adjustment, it is again

tightened with knob 8b.

TAPER THREADS: To set the table for
taper grinding it is necessary to loosen the
square screw 10b under the taper setting hand
knob 10a on the front of the table. A hand crank
furnished with the machine fits the screw. Six
socket head screws holding clamps at the ends

of the table must be loosened. The upper part
of the table containing the headstock assembly
and supporting the tailstock assembly can then
be swiveled to the desired taper. The gradu

ations on the clamp at the right end of the

table represent included taper per foot in

decimals of an inch. To grind a thread of .75"

included taper per foot for example, the table
is swiveled to the .75" graduation. The taper
setting should then be checked. The fine ad
justment can be made by tightening the square
screw 10b under the hand knob, then turning
the knob to get the exact adjustment. The six
socket head screws in the clamps at the ends
of the work table are then tightened.

The lead control must be adjusted to elim

inate the shortening of the lead caused by the
angular setting. On the sliding bar seen through
the opening 8c the lower graduations indicate
taper per foot in inches. If the taper being

ground is .75" included taper per foot for

example, the bar is moved to the left to the .75"

graduation.

The dresser must be adjusted for grinding
the thread form normal to the work axis. Thus
the angular setting of the dresser must equal
half the included angle of the tapered work

piece. These angles are listed in handbooks
under “

Tapers and Corresponding Angles”.



LEAD PICK-UP: By means of this device
the work table can be moved to match pre-cut
threads with the grinding wheel. The lead pick
up assembly should be tensioned so that the
hand crank can be turned with moderate force
without binding. It should not turn too freely.



How to obtain the proper tension is explained
on page 205.

There are two methods of picking up the

lead. One method is used when rough cut
threads are to be finish ground; the other is
used for a thread that is too long to be ground
at one setting and must be ground by steps or
turned end for end.

For rough cut threads the lead is picked up
with the wheel running and the coolant valve
closed so that sparking is visible. The hand

crank furnished with the machine is placed on

the square end of the screw shaft 12a and turn

ed in the direction necessary to align the wheel
with the thread. The wheel slide is then brought
toward the work and the position of the table
adjusted with the hand crank until the wheel is
in the center of the thread as indicated by the
sparking.



To pick up the lead from a portion of the
thread that is finish ground the method is dif
ferent because the wheel must not cut into the
finished thread. The part of the thread that is
to be matched to the wheel should be blued.
The table should be moved with the hand crank
as described above and the wheel brought to



ward the work very carefully. When the wheel
removes the blue, equally on both sides
thread form, it is matched exactly.

Available as extra standard equipment are

bench-type lead pick-up fixtures as shown in

the “



700 section”. Machine down time for the

lead positioning canbe eliminated during quan
tity production runs, by enabling the operator
to place the work drive dog on the next work

piece while one work piece is being ground.

POSITIONING THE WORK SPINDLE: For

loading work pieces in special work holding
fixtures which are accessible in one position
only, the work spindle canbe rotated manually.
This is done by engaging the square end shaft

extension on the front of the work drive door

with a hand crank which is furnished with the

machine,

HYDRAULIC WORK SPINDLE DRIVE: The

variable speed hydraulic motor in the work

’ of the











406

SMALL y
MEDIUM
LARGE

----

OPERATING INSTRUCTIONS

HYDRAULIC MOTOR

7^

r

SLOW

nJJ

ImI

WORK SPINDLE DIRECTION AND SPEED CONTROL

I

WORM

RATIO

40:1

head is supplied with oil under pressure from
the hydraulic pump. This motor drives the
work spindle through a V-belt and a worm and
worm gear. Three-step pulleys used with the
motor give an unusually wide range of work
speeds. The motor speed during rapid trav
erse is controlled by a lever on top of the work

WORK SPINDLE DRIVE

\

FAST

i^>

HYDRAULIC PANEL

head and the rapid traverse orifice.



WORK SPINDLE SPEEDS: The upper left

drawing represents the variable speed, hydrau

lic work drive motor with the lever for con
trolling the speed during rapid traverse. When
the rapid traverse plunger in the hydraulic con

A

trol panel is depressed, the motor is. shifted

into high speed, and the control lever becomes

effective. The motor speed varies from 1,200

to 2,000 rpm, depending on the adjusted posi

tion of the lever and the orifice.

For

high

work speeds, used when returning
idle to the start of a cut, the lever should be
moved to the fast position, the center orifice

dial should be turned to “F” and the rapid
traverse plunger in the hydraulic control panel

depressed.

Under these conditions the hydraulic motor
runs at approximately 2,000 rpm. With the
V-belt on the small diameter of the motor
pulley and the large diameter of the worm shaft
pulley, the work spindle turns at approximately
35 rpm. With the belt on the medium pulley
diameters, the spindle speed is approximately
100 rpm. When the large diameter of the motor
pulley, and the small diameter of the worm

S*








407

OPERATING INSTRUCTIONS

shaft pulley are used, the spindle speed is ap
proximately 270 rpm.

If these speeds are found to be too high the
control lever can be moved toward the slow
position until a suitable speed is obtained. At

the extreme slow position the motor speed is

1200 rpm and the spindle speeds are 21, 60 or
162 rpm depending on the location oftheV-belt.

If lower rapid traverse speeds are needed the
orifice dial can be adjusted.

NOTE: It is not advisable to attempt

to grind with the rapid traverse plunger
depressed. Rapid traverse is to be used only

when approaching or leaving the work. The

FEED plunger should be depressed during
grinding. When this plunger is depressed the
upper orifice dial regulates the work speed

during table travel to the left, and the lower

dial during travel to the right.

Infinitely variable speed adjustments, with

in the range of the motor,

are

available by ad

justing the orifices between the “F” and “S”
positions. The speqd range is changed by
changing the position of the belts on the three-
step pulleys.

The hydraulic motor is reversed at the end
of each stroke by the direction plungers in the
hydraulic control panel.

The chart of rapid traverse speeds shows
the rpm obtainable by the use of the different
grooves on the three-step hydraulic motor
pulley, and at the extreme positions of the
motor

control

lever. The charts of work speeds
during feed may be filled in by the customer
for his particular grinder.



WORK RPM DURING FEED (Grinding)

To be filled in for individual machine

pulley used

Groove of

hyd. motor

RPM DURING FEED TO LEFT

Controlled by upper orifice dial

Markings on dial

6

3

S

12

9

Large

Medium

Small

RPM DURING FEED TO RIGHT

Controlled by lower orifice dial

Large
Medium




Small

MOUNTING DIMENSIONS: The drawings
that follow show dimensions of the tapered
hole in the tailstock, the work spindle nose and
the machine table. The sectional drawing of the
tailstock shows dimensions to be used if spe
cial centers are required. Dimensions shown

on the spindle nose drawing are to be used for
fitting chucks, adapters or work holding fix
tures. The table dimensions shown will be
found useful if steadyrests or rough locators
are required.

15

F





WORK RPM DURING RAPID TRAVERSE

With rapid orifice dial set at “F”

Groove of
hydraulic

motor pulley

used
Large
Medium

Small

Position of motor control lever

Slow

162

60

21

408

Fast

270

100

35

NO. 8 B. & S.

± .001

.898—,

TAPER

M

. /AA

.

77/77fr.

1

i

J

7777ZZZZZZZZL

**16

TAILSTOCK TAPER

OPERATING INSTRUCTIONS

NO. 8 B & S TAPER

.500 TAPER PER FOOT*

NO. 16 JARNO TAPER

.600 TAPER PER FOOT

V777ZYK/k

xwww

L l| DIAM. HOLE

THROUGH SPINDLE

y .

A

i

T

2

—

/

16

DECIMAL DIMENSIONS ±.005

UNLESS OTHERWISE SPECIFIED

2.500

3

16

1

2 8

+ .0003

-.0001

3.000

1.393

±.0015

6.000

t

m

-.001

*- 2.000

WORK SPINDLE ADAPTER AND CENTER

a V-belt and two-step pulleys. Pulleys are
available for wheel speeds of 7,000 and 9,000
surface feet per minute. The table below shows
the pulleys used for wheels from 18" diameter

1

to 13" diameter.

~ -14 N.C. TAP 11 DEEP, 8 HOLES

4-

2.500

1.393
r-

—

1.393

1.393

2.500

,

2.500

2

h

MIN.

8

|

diam

SCRAPED

<£ OF WORK SPINDLE-'""

MAX. SWING Uj

'

MACHINE TABLE DIMENSIONS

<£ OF WHEEL-"

SPINDLE

WORK

CENTER

WHEEL SPINDLE SPEEDS: A constant

speed electric motor drives the spindle through

Wheel
Diam.

18
17
16
15

14
13

PULLEY MARKINGS

(RPM OF WHEEL SPINDLE)

For 9,000 Ft./Min.

For 7,000 Ft./Min.

1910
2040
2150
2290
2450
2640

1485
1575
1670

1780
1910
2040

TAILSTOCK: The tailstock center quill is

spring operated. A lever on top of the tailstock

withdraws the center from the work and a

knurled knob on top is used to lock the quill,
if desired. The large knurled nut at the right
end of the tailstock adjusts the spring tension

the center and the smaller knurled nut. acts

on

stop. It should be adjusted so that the

as a
center will not hit the wheel when work is

changed.

409

OPERATING INSTRUCTIONS

: \

LEAD CHANGE GEAR COMPARTMENT

CHANGE GEAR INFORMATION

Mounting of gears:

a without compound gear

m

R

i

(£ OF SPINDLE

b with one compound gear

SPACER

2

i

T

m

t i i

r _ r

t

<£ OF SPINDLE

c with two compound gears

m

£

4 OF SPINDLE

SPACER

SPACER

T

I

I

2

3 f

T7

. m

ttttt

(| OF SCREW

m

T

w

5

a —

OF SCREW

4

3 —

W

<£. OF SCREW

-*

— INNER TRAIN

OUTER TRAIN

INNER TRAIN

— OUTER TRAIN

IDLER QUADRANT

LEAD CHANGE: Change gears furnished

with the machine can be assembled in the

change gear compartment to obtain a wide
range of leads. The gears are alloy steel,
treated and finished with a tooth shaving pro
cess that removes all irregularities and pro
duces the highest precision gear available with

in commercial means. The gear teeth are 14
pitch, 20 degree pressure angle with 3/4

face. They are kept constantly lubricated by
an oil pump. Tables on the following pages
show the gears to use and where they are to
be mounted to obtain the desired lead.

In the change gear compartment, the gear
quadrant has four slots, designated slot 1, slot
2,

slot 3 and slot 4. Diagrams at the left show
howto mount the gears. There should be about
.003

” backlash between all mating gears when

they are assembled.

The lead screw gear should be mounted
first, then the other gears on the quadrant. The
spindle gear is mounted next, and the quadrant
positioned and locked allowing the necessary
backlash between the spindle gear and the gear
on the quadrant that meshes with it.

heat

” wide





410

OPERATING INSTRUCTIONS

CHANGE‘GEAR CHART

R. H. THREADS with Standard 6 Threads per inch Lead Screw using

THREADS

PER INCH

2
2-1/4
2-1/2

2-3/4

3

3-1/4
3-1/2

4
4-1/2

5

5-1/2

6

7

8

9

10
11
11-1/2
12

13

14

16

18
20
21
22
24

26

27
28

32

Ex-Cell-0 Style 35 and 35-L Precision Thread Grinders

standard gears furnished with machine

NUMBER OF TEETH

SPINDLE

84
84
84
84
84
84
48
42
42
42
42
42
48
84
84
84
84

48
84
84
48
84
42
42
48

42

42
42
48
48
42

SLOT I

63

56
63
63
63

56
63
63

56
63

63
63

56

56

56

56

56

56

56

56

56

56

56

56

56

56

56

56

56

56

56

SLOT 2
28/56

28/56
28/56
28/56

28/56
28/56

28/56
28/56
28/56
28/56

28/56
28/56

28/56

SLOT 3

70
63
56
56

56

70
70
63
56

56
56

56/28-70
56/28-63
56/28-63
56/28—6 3
56/28-70
56/28-63

56/28

56/28-70

56/28
56/28-63
56/28-63
56/28-63
56/28-63
56/28-63

56/28
56/28
56/28

56/28

SLOT 4

70

63

63

63

70
63
63
63

SCREW

56

63
70

77

84

91

56

56
63
70
77
84

i 12

56
63

70
77

46
84

9

1

56

112

63
70
84
77
84

9 i

I08
1 i 2
112

411

OPERATING INSTRUCTIONS

CHANGE GEAR CHART

L. H. THREADS with Standard 6 threads per inch Lead Screw using

THREADS

PER INCH

2
2-1/4
2-1/2

2-3/4

3-1/4
3-1/2

4

4-1/2

5

5-1/2

6

7

8

9

10
11
11-1/2
12

13

14

16

18
20
21
22
24

26
27

28

32

Ex-Celi-0 Style 35 and 35

standard gears furnished with machine

SPINDLE

84
84
84
84
84
84
48
42

42

42

42

42

48
84
84
84
84
48
84
84
48
84

42

42

48

42

42

42

48

48

42

SLOT 1

70
70
63

63

63
63
63
63
63
63
63

63
63

56/28
56/28
56/28
56/28
56/28
56/28
56/28
56/28

56/28
56/28
56/28

56/28

56/28

56/28

56/28

56/28
56/28

56/28

-L Precision Thread Grinders

NUMBER OF TEETH
SLOT 2

28/56
28/56
28/56
28/56
28/56

63

SLOT 3

28/56
28/56
28/56
28/56
28/56
28/56

28/56
28/56

63

63
63
63
63
63
63
63
63
63

63
63

63
63
63
63

56

SLOT 4

SCREW

56

63

70
77

84

9

1

56
56

63

70
77
84

112

56
63

70
77

46

84

91
56

M2

63

70
84
77
84

91

108

112

I 12

412

OPERATING INSTRUCTIONS

CHANGE GEAR CHART

R. H. THREADS with Standard 6 Threads per inch Lead Screw

THREADS

PER INCH

1

3-3/4

15
17

19

23
25

29

30
34

Ex-Cel 1-0 Style 35 and 35-L Precision Thread Grinders

*Extra standard gears for pitches listed

SPINDLE

81
81

81
81
72*
18
18

51

“
12
15*

SLOT I

56
56

56

63

56
56
56

75/25*

56

75/25*

NUMBER OF TEETH

SLOT 2
25/75*
28/56

SLOT 3

56/28

56/28
56/28
56/28

56/28

56/28

63

70

70

SLOT 1

63
63

56
63
70
63

56

63

56

SCREW

12*

105*
105*

119*

111*

92*

100*

87*

105*

85*

36

38
40
42

43
44

48

50
56

60

64

68
72

80

12

15*
15*
15*
72*

15*
12

51*
15*
15*

15*

15*

51*
15*

75/25*
75/25*
75/25*
75/25*

56/28

75/25*

75/25*
56/28
56/28

56/28
56/28
56/28
56/28

56 /28

70
70
70

70

75/25*

70
70

75/25*

75/25*

75/25*
75/25*
75/25*
75/25*

75/25*

56
36*
36*
36*
67*

36*
36*

67*
67*
67*
67*
67*
67*

67*

81

95*

100*
105*

86*

110*
112

75*

70
75*
80*
85*

108
100*

413

OPERATING INSTRUCTIONS

CHANGE GEAR CHART

THREADS

PER INCH

1

3-3/4

15

17

19

23
25

29

30
34

Ex-Cel 1-0 Style 35 and 35-L Precision Thread Grinders

L. H. THREADS with Standard 6 Threads per inch Lead Screw

*Extra standard gears for pitches listed.

SPINDLE

84
84

84
84
72*

48
48

54*
42

45*

SLOT I

70

63
56/28
56/28
56/28
56/28
56/28

75/25*

56/28

75/25*

NUMBER OF TEETH

SLOT 2

SLOT 3
25/75*

28/56

63
63

63

63

63
70
63

70

SLOT 4

SCREW

i*2*

1

05*

105*
119*
II4*

92*

1

00*
87*

105*

85*

36
38
40

42
44
48

50
56

60

64

68
72

80

42 84
45*
45*

45

’
45*
42

54*
45*

45*
45*

45*
54*

45*

75/25*
75/25*
75/25*

75/25*
75/25*

75/25*

56/28
56/28

56/28
56/28

56/28

75/25*
75/25*

36*
36*
36*
36*

36*

36*

36*

70

70

70
70

70

67*

75/25-67*

75/25-67*
75/25-67*
75/25-67*

75/25-67*
56/28-56

56/28-56

95*

100*

105*
110*
112

75*
70
75*
80*

85*

108
100*

414

OPERATING INSTRUCTIONS
CHANGE GEAR CHART

Ex-Cell-0 Style 35 and 35-L Precision Thread Grinders

R. H. METRIC LEADS With Standard 6 Threads per inch Lead Screw

*Extra standard gears for metric leads listed

M.M.

LEADS

■5

.6

.7

.75

.8

•9

1.0

1.25

SPINDLE

45*
54*
63*

60*
72*

72*
80*

1

00*

SLOT I
75/25*

75/25*
75/25*

72/27*
75/25*

72/27*
72/27*
72/27*

NUMBER OF TEETH

SLOT 2

SLOT 3

70

70
70
70

70
70

70
70

SLOT 4

36*
36*
36*

36*

36*

36*

36*

36*

SCREW

127*
127*
127*

127*
127*

127*

127*

1

27*

1-5

1.75

2.0

2.25

2.5

2.75

3.0

3-5

4.0

4.5
5-0

6.0

60*

70*
80*

90*

100*
110*

60*
70*
80*

90*

100*

60*

56/42*
56/42*

56/42*

56
56
56

56

56

56

56/42*
56/42*
56/42*

25/75*

28/42*
28/42*
28/42*

28/42*
28/42*

36*

36*
36*
36*

36*
36*

127*
127*
1

27*
127*
127*

127*
127*
127*
127*
127*
127*

127*

415

OPERATING INSTRUCTIONS
CHANGE GEAR CHART

Ex-Cel 1-0 Style 35 and 35-L Precision Thread Grinders

L. H. METRIC LEADS with Standard 6 Threads per inch Lead Screw

♦Extra standard gears for metric leads listed

HUMBER OF TEETH

M.M.

LEADS

•5

.6
.7

.75

.8

•9

1.0

1.25

SPINDLE

45*

54*

63*
60*

72*
72*

80*

100*

SLOT I

SLOT 2

75/25*
75/25*

75/25*
72/27*

75/25*
72/27*

72/27*
72/27*

SLOT 3

SLOT 4

70
70
70

70
70
70

70

70

SCREW

127*
127*
127*

127*
127*

127*

127*
127*

1.5

1.75

2.0

2.25

2.5

2.75
3-0

3.5

4.0

4.5

5.0

6.0

60*
70*

80*

90*
100*
110*

60*

70*
80*

90*

100*

60*

56/42*
56/42*
56/42*

56/42*
56/42*

36*
56

56
56

56
56

56

56 / 42*

25/75*

56
56

56
56
56

28/42*
28/42*

28/42*
28/42*

28/42*

127*
1

27*

127*
127*
127*

127*

127*
127*

127*
127*

127*
127*

416

OPERATING INSTRUCTIONS

CHANGE GEAR CHART

M.M.

LEADS

•35

-4

•5

.6
.7

.75 •

.8

•9

Ex-Cell-0 Style 35 and 35-L Precision Thread Grinders-

R. H. METRIC LEADS with 4 M.M. Metric Lead Screw

*Extra standard gears for metric leads listed

NUMBER OF TEETH

SPINDLE

63*
72
45*

54
63*

42
48
54

SLOT 1

75/25*
75/25*
75/25*

75/25*
75/25*

56
56
56

SLOT 2

SLOT 3

67*
67*
70
70
70

56/28
56/28
56/28

SLOT 4
56/28

56/28

36*
36*

36*
56

56

56

SCREW

120
120
120
120

120

112
120

120

1.0

1.25
1-5
1-75

2.0

2.25

2.5

2.75
3-0

3-5

4.0

4.5

5.0

48
60

72

42

48
54

60
66

72

42-
48

54

60

56
56

56
56

56

56
56

56
56

56
56

56
56

28/56
28/56

28/56
28/56

56/28
56/28

56/28

56/28-70
56/28-70

56/28-70
56/28-70

56/28-70
56/28-70

70
70

70

70
70

70

70

96

96
96

48

48
48
48

48
48

96
96

96

96

6.0

72

56

28/56

70

96

417

OPERATING INSTRUCTIONS

7T

rfi

\

/

DETERMINING CHANGE GEARS FOR
SPECIAL LEADS: For special leads not listed
in the change gear charts the following infor
mation is supplied to help customers who wish

to make special set-ups.

In the following equations
R = Required Gear Ratio,

b

R

= Maximum Gear Ratio

max.

and

R . =

min.

Minimum Gear Ratio

With the standard 6 threads-per-inch lead

screw the required gear ratio equals:

R a 6 x Lead

b

b. for the style 35-L grinder

/

R

R . =

max.
min.

= 1,00208 R

.99792 R

s
s

The following gears are regularly furnished
with the standard machine having a 6 threads
per-inch lead screw:

Spindle gears with 42, 48 and 84 teeth,
Screw gears with 48, 56, 63, 70,77, 84, 91,

108 and 112 teeth,
Idler gears with 56, 63 and 70 teeth,

Compound idler gears with 28/56 teeth (For

1 to 2 or 2 to 1 ratio)

With these gears the ratios shown on page
420 are possible.

When a gear train is planned, the

of the change gear compartment must be con

sidered. Before additional gears are ordered,

it is advisable to make a scale size layout for
checking the limitations.



With

standard 14 D.P., 20° P.A. spur gears,
the maximum possible ratio between spindle
and screw is 3.85.

The range of spindle gears is 42 to 120

teeth.

The range of screw gears is

32 to 127 teeth.

An odd number of gears is required for

right hand leads, and an even number for left
hand leads. (A compound gear is considered
as a single gear).

The maximum total number of gear teeth
on spindle gear plus screw gear must not ex
ceed'

195 teeth.

limitations

-





By the use of the lead control which allows

plus or minus .040" variation per foot on the

Style 35 grinder, and plus or minus .025"

the Style

35-L

grinder, the following maximum

on

and minimum ratios are permissible:

a. for the style 35 grinder:

R

R min. “

max.

= 1.00333R

.99667 R

s

s

418

The layout of the gear train is facilitated

by the halfsize drawing on page 419. The cen
ter positions are shown as follows:

A. Positions of adjustment of spindle gear

in relation to idler quadrant.

B. Position of adjustment of spindle gear

in relation to idler quadrant with Spin

dle-Type Relieving Attacnment.

C. D, E & F Range of idler gear center

positions in slots 1, 2, 3 & 4.





OPERATING INSTRUCTIONS

GEAR QUADRANT

HALF SIZE

1

" 1 2

1 2

1

1

( r

I

1

I

i

2

D

I

3

4

\

/ I

CENTER OF SCREW GEAR

Example: Style 35 Grinder

lead = .4445 right hand
R = 6 x .4445 = 2.6670

s

R

^ min.

= 1.00333 x 2.6670 = 2.6759

max.

.99667 x 2.6670 = 2.6578

Selected: 84 tooth spindle gear

63 tooth screw gear
2/1 compound

2.66667 ratio

i

V

1 5

84 x 56 x 1
63 x 28 x 6

/

INTERFERENCE

LINE

.4445

.44444

.00006

✓

3 16

Check:

Lead desired
Lead obtained

Variation to be compensated by
Lead control

Variation in one foot length

.00006

.44444

x 12 = .00162

419

OPERATING INSTRUCTIONS

RATIO

.1875
.19444
.21428
.22222
.23077

.25
.26373
.27273
.28571
.3
.31169
.33333
.34285
.375
.375
.38095
.38889
.42857
.42857
.46154
.5
.52174
.52747
.54545
.57143
.6
.62338
.66667
.68571
.75

.7619
.77778
.85714
.88888
.91304

'.92308

1.

1.04348

1.05494

1.09091

1.14286

1.2

1.24676

1.33333

1.37142

1.5

1.5238

1.55556

1.71428

1.82609

1.84616

2.

2.08687

2.18182

2.4

2.66667

3.0

GEARS

SPINDLE

42
42
48
48 108
42
42
48
42
48

' 42

48
42
48
42
84
48
84
48
48

84
42
48
48

84

48

84
48

84
48

84
48

84

48
48

84

84

84
48

48

84

48

84

48

84

48

84

48

84

48

84

84

84
48
84

84

84
84

SCREW COMPOUND

112

108

112

91
84
91
77
84
70
77
63
70
56

112

63

108

56

112

91
84
46
91
77
84
70
77
63
70
56
63

108

56

108

46

91
84
46

91
77

84
70
77
63
70

56
63

108

56
46

91

84
46
77

70

63

56

1 to 2
1 to 2
1 to 2

1 to 2
1 to 2
1 to 2
1 to 2
1 to 2
1 to 2
1 to 2
1 to 2

1 to 2
1 to 2

1 to 2
1 to 2

1 to 2
1 to 2

1 to 2

none

1 to 2

none

1 to 2

none

1 to 2

none

1 to 2

none

1 to 2

none

1 to 2

none
none
none

2

to

1 to 2

none
none
none

2 to 1

none

2 to 1

none

2 to 1

none

2 to 1

none

2 to 1
2 to 1
2 to 1

none

2 to 1
2 to 1
2 to 1
2 to 1
2 to 1
2 to 1

2 to 1

1

The following ratios can be obtained with extra

change gears: (To be filled in by customer.)

RATIO SPINDLE

SCREW COMPOUND

420

OPERATING INSTRUCTIONS

CHANGING WHEEL PULLEYS: The wheel
spindle pulleys are made so that they can be
put on and taken off the shaft without the use
of a hammer, or without any force being ex
erted that may be carried to the spindle bear
ings.

WHEEL PULLEY

THREADED DISC

^ HEXAGON

SHOULDER SCREW

TAPER END OF

GRINDING SPINDLE

To change a wheel pulley, the belt guard

cover and the belt are removed. The pulley is

removed by turning the hexagon head shoulder
screw shown in the drawing. This screw has
left-hand threads. The shoulder on the screw
pushes against the threaded disc to remove the
pulley from the tapered spindle shaft. The

threaded disc has right-hand threads. It is re

moved from the pulley with a spanner wrench.

The shoulder screw and disc are then put in the

selected pulley and assembled to the shaft.
Care must be taken that the key is in place.

IMPORTANT: The operator is cautioned to
change the pulleys as described above, without
the use of a hammer or bar. The balls in the
spindle bearing rotate in accurately lapped

raceways. Following the above suggestions
will prevent marring these raceways and in
sure satisfactory spindle performance.

When the belt is replaced it should be

checked for proper tension. A belt that is too
tight prevents smooth spindle performance.

MOUNTING GRINDING WHEELS:

The

wheel must be checked for cracks before it is
mounted on the spindle. If no cracks are vis
ible, a further check can be made by holding
the wheel in one hand, resting the inside diam
eter on one finger,

and tapping it lightly with a

screw driver handle. It snould nave a ringing
sound. If there is some question regarding the
soundness of the wheel, a comparison can be



made with another wheel of the same type.



Some practice and experience willbe required
since wheels of different types do not sound the
same. It is generally safe to assume that a
wheel that sounds dead, or one that has no ring

is cracked. A cracked wheel must never be

put on the machine.

To change grinding wheels, the cover at
the side of the wheel guard is first removed,
then the eight screws holding the large flange
of the spindle adapter. All parts should be
wiped clean. The new wheel is then placed on
the spindle with the wheel washers in place.

One washer only must be placed at each side.

Wheel washers are made of compressible

material which helps prevent the wheel center
from setting up strains in the wheel when the
screws are drawn up. Absence of washers

might cause the wheel to crack either when it

is being clamped or during operation.



If the wheel does not fit freely the hole
mustbe scraped out. Forcing it on the adapter
might cause it to crack.

The identification marks on the wheel

should be kept toward the operator. Mounting
the wheel the same way each time will save

considerable dressing.

The adapter flange may now be replaced
and one of the cap screws tightened slightly.
Next, the cap screw opposite the first one
should be drawn up. The screw next to the
first one is then tightened slightly and the one
opposite this one. This procedure should be
repeated, working around the wheel until all
screws have been tightened slightly.



Now the screws can be tightened a little

more, working around the wheel in the same

manner, until all are drawn up uniformly tight.
They should be snug and tight, but should not
be hammered or forced.

The coolant nozzle is adjusted so that it

clears the wheel when the wheel is turned by



hand. The wheel should revolve freely and not
bind or touch the nozzle or wheel guard. The



guard can be adjusted backward or forward by

the clamping nut at the side of the wheel spindle

421

OPERATING INSTRUCTIONS

oiler. It is retained for sideways adjustment
with three vertical cap screws arranged below

the spindle oiler.
SUMMARIZED INSTRUCTIONS FOR SETTING

THREAD GRINDER TO NEW WORK

1. The grinding wheel spindle must be

set to the required helix angle.

2. When worms are ground, the Three

Way

Cradle Type Dresser, or the Universal
Cam Type Dresser is usually set to corres
pond with the helix setting of the wheel spindle.

3. Change gears must be assembled to

obtain the required lead. From .003" to .008"

backlash must be provided between change

gears.

4, The centers must be clean and the work

head center must run true.

5.

The spindle direction control valve
must be set for either right or left hand thread
to conform to the mounting of the change gears.

6. The table control dogs must be set for

the correct length of strokes,

7. The proper grinding wheel should be

selected, (See section 1,000 of this manual.)

8. The grinding wheel must be checked

for defects and correctly mounted.

9.

The proper work speed and wheel speed

should be selected.



10. Manual infeed should be used when the
first workpiece is ground. It is always advis
able to keep the size near the high limit of the
work piece,
the grinding wheel will have a tendency to grind

the work undersize.

for as the dressing diamonds wear,

11. The thread form of tne first piece
should be inspected and any necessary dresser
adjustments made.

12. The automatic feed and automatic
dressing should be adjusted as described on
pages 403 and 404.



422

MAINTENANCE

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-1

Ex-Cell-O Precision Thread Grinders are

designed and built to require a minimum of

maintenance care. Such care includes lubrica
tion as explained in section 300, maintenance of
the proper fluid levels in the hydraulic reser
voir and the coolant tank, and removal of grind
ing sludge from the tank.

CLEANING THE COOLANT TANK: When
the machine is used in continuous production
the coolant tank should be thoroughly cleaned
once a week. On tool room work the tank should
be cleaned once a month. However, the length
of time before the tank should be cleaned will
vary with the type of work being done.

HYDRAULIC OIL: One of the most im
portant units for the satisfactory operation of

the machine is the hydraulic system. This
system will operate without any noticeable

wear as long as clean hydraulic oil is used.

When the reservoir

that the receptacles and funnels usedare

is

filled, care mustbe taken

clean.

This will prevent possible contamination with

other fluids or the entrance of dirt or grit into
the system. The hydraulic oil used as fluid

medium should be extra light, of Saybolt vis
cosity 120 seconds at 100°F. The reservoir
must be kept filled.







HYDRAULIC SYSTEM: (Additional infor-

mation on hydraulic service

is

on

pages 603 and

604). The oil filter, mounted with the hydraulic
pump and electric motor at the rear of the ma
chine base, requires attention about twice a
week. The handle protruding from the top of
the guard should be turned in either direction
several times. This cleans the filter cartridge
of any foreign particles that may have been de
posited.





The panel control pressure can be checked

B0 PANEL CONTROL PRESSURE

ADJUSTMENT

BP ACCESSORY PRESSURE ADJUSTMENT

by removing the pipe plug BH in the main hy
draulic panel and inserting a pressure gage.
The pressure should be from 110 to 125 pounds

per square inch. To adjust the pressure it is

necessary to remove a cover plate directly be

hind the panel in the back of the machine base.
Two hexagon brass cap nuts BO and BP are in

this opening. The adjusting screw locked by

the upper cap nut BO controls the panel pres
sure.











BH PIPE PLUG FOR CHECKING PANEL

CONTROL PRESSURE

BQ PIPE PLUG FOR CHECKING ACCESSORY

PRESSURE

The accessory pressure can be
removing the pipe plug BQ in the main hydrau
lic panel. The adjusting screw locked by the
lower hexagon cap nut BP in the opening be

hind the panel controls the accessory pressure.
This pressure should be from 130 to 140 pounds
per square inch. When the grinder is equipped

checked by




with the automatic start after dressing valve

501

MAINTENANCE

(optional equipment) the accessory pressure
should be set between 175 and 185 pounds per
square inch.

GRINDING SPINDLE SERVICE: It is rec
ommended that when a grinding spindle needs
service, the work be done in the Ex-Cell-O

Service Department. In this department are

the special tools, inspection equipment, and
experienced mechanics necessary to give the

work the extraordinary care required of a
precision spindle. A spindle thus serviced is
given the same guarantee as a new one.

The service received from a spindle de
pends almost entirely on the care, cleanliness
and skill of the mechanic who installs or re
places the precision ball bearings. For this
reason the Ex-Cell-O Corporation assumes no
responsibility for

the performance of bearings
not installed in its own service department.
However, for plants that maintain their own
spindle service departments, the following in
formation is offered:

Ex-Cell-0 Precision Ball Bearings are
interchangeable as a unit, but the individual
parts are not. Because the inner and outer
races are developed in sets, they must be



assembled in the spindle in the position indi
cated by markings. The inner race and both
of

the outer races have the bearing serial num

ber and arrows etched in a prominent position

so that, in assembly, these numbers will be
opposite each other, and read in the same di
rection, facing the operator.

When new bearings are ordered, the serial

number of the old bearings must be specified



so they can be duplicated exactly, and have the

same running characteristics.





CARE OF GRINDING WHEELS: Wheels
notin use should be carefully stored flat. They
should be wiped clean and stacked not more
than twelve high on a smooth, flat surface. If

wheels are stored vertically the coolant oil

which saturates the wheel when in use, will

work down and disturb the balance.






ELECTRICAL MAINTENANCE

SERVICE: Electrical equipment of the
highest quality has been used in this machine.
When trouble is experienced, the Ex-Cell-0

Service Department, or the nearest service
department of the supplier of electrical equip

ment should be called. This equipment re
quires the attention of trained men. Under no
conditions should an uninstructed person be

allowed to work on this machine, as the re

sulting damage may far exceed the ordinary
service costs.

For plants having the specialists available

to take of such repairs, the following in

formation including a marked picture of the

electric panel and an elementary diagram of
the complete electric circuit of a standard ma
chine will be helpful.

GENERAL INFORMATION: The electrical
control equipment should be kept clean and dry.
No part needs oiling; all contactors operate in
free-fitted slides. Contacts are silver and are
not harmed by discoloration or slight pitting.

The contacts
ly wastes the contact material. Replacement
is necessary only when the silver has worn

thin.

should never be filed. This mere






The thermal unit does not deteriorate from
operation. Continued overcurrent through the
heating element raises its temperature, finally
melting the alloy and permitting the ratchet
wheel to rotate. The latch engaging the ratchet
wheel is then released, allowing the overload
relay contact to open, thus disconnecting all
lines to the motors. A few moments have to



be allowed for the melted alloy to solidify be

fore the relay is reset.



MOTORS: Four motors are furnished with
the standard machine: the hydraulic pump
motor, grinding wheel motor, coolant pump
motor and dresser motor. In addition, a motor
for the suction hood fan, and one for the refrig
eration-type coolant unit are supplied when
those accessories are ordered.







502

maintenance

LI L2 L3

30

10 OVERLOADS

29

no VOLTS

hi

n

CD

\£-

□

H

o

SUCTION FAN (OPTIONAL)

1

— H.P. MOTOR

20

io :

o

REFR. (OPTIONAL)

THERMOSTAT

LSDF

-o^=xy

LSDR

.-A A A A

L

NOTE:

after dressing is shown in dash-dot lines (
equipment is used jumper between terminals 9 and 19 is
omitted.

lines (

PUSHBUTTONS AND SWITCHES ON PANEL

1. Start Hydraulic Pump

2. Stop Hydraulic Pump

3. Start Wheel and Coolant Pump

4. Stop Wheel and Coolant Pump

5. Hand Cycle

6. Master Stop

7. Start Dresser

8. Stop Dresser

SVI

V v V V V

Optional equipment for starting machine automatically

Other optional equipment is shown in dash-two-dot

— • • —

ON LEFT SIDE OF MACHINE

DF

5

0

(

PILOT

LIGHTS

\ DR

A

).

—Automatic Cycle

15

A

JL

8

O O

H
4

0

o o

c

n

38

DF'

3

TRI

—

«»

°

JUMPER i 1

y A

PRESSURE SWITCH

0

Z—n To-

0

17

■n T o—H

0

L

19 ‘ 9

O

df

’

4

9

TRI

O

------

T

— - —

). If this

0 9

i

I

i

l

__

-----

0

— H

14

^

>

H0

j

H

4

4

c

4

4

DF

DR

4

0 0
0 0
0 0

PUSH BUTTON

PANEL

4

c

r\s>

<T\^>

<f\p-

CTSj>

WHEEL MOTOR

kfvo

----

0V>

AAA/VVV

<5\S>

}—<5Vo

DRESSER MOTOR

REFR. UNIT (OPTIONAL)

— H.P. MOTOR

----

4

CT'.jd-----

« • ■ — • • *

0
0

DRESSER

STATION

HYDRAULIC

PUMP MOTOR

3 H.P.

1T1

1T2

1T3

COOLANT

PUMP MOTOR

— H.P.

4

2T1

2T2

2T3

3 H.P.

3T1

3T2

3T3

BRAKE

4T1

4T2

4T3

— H.P.

12

5T1

;t3 >

ELEMENTARY

ELECTRICAL DIAGRAM

503

maintenance

OVERLOAD

RELAYS

TERMINAL

BLOCK

WHEEL AND

COOLANT PUMP

FORWARD

HYDRAULIC

PUMP

REVERSE

ELECTRICAL PANEL

(OPTIONAL)

REFRIGERATION

(OPTIONAL)

CONTROL

TRANSFORMER

FUSE BLOCK

THE HYDRAULIC PUMP MOTOR is mount
ed on a separate base at the left of the machine.
It is started by pressing button 1 and runs

continuously until it is stopped by pressing

button 2 or the master stop.

THE WHEEL MOTOR is mounted on the

cross slide. This motor and the coolant pump
motor are started by pressing button 3. Both
of these motors run until they are stopped by
pressing button 4 or the master stop.

THE COOLANT PUMP MOTOR is mounted
on the coolant tank. It is started and stopped
with the wheel motor. Connection is made with
an attachment plug and receptacle.

THE DRESSER MOTOR: When the start
button 7 is pressed, and the selector switch 8

is at the “on” position, the dresser will com
plete one cycle and stop.

REFRIGERATION UNIT MOTOR (Optional
equipment): This motor is mounted with the
cooling unit in the coolant tank. Connection is
made with an attachment plug and receptacle.
The starter for this motor is operated by push
buttons 3 and 4. The motor is controlled by
a thermostat after the wheel is started.



SUCTION HOOD MOTOR (Optional equip

ment): This motor is started at the same time
as the wheel motor. It is connected to the 110
volt control circuit.

NOTE: If the over load for this motor

ates it will not stop the machine.

An attachment plug and receptacle is pro
vided for connecting the suction hood. To pre
vent overloading and burning out the control
transformer it is very important that no other
devices be attached to this receptacle.



A SOLENOID operates the brake on the

dresser motor. While the motor is operating

this solenoid is energized from two of the

motor lines.



LIMIT SWITCHES: LSD F and LSD R
are the contacts of switches mounted on the
dresser. On the Universal Cam-type Dresser
there are two micro switches. On the other
external dressers there is one switch with two
circuits.

oper








504

HYDRAULIC ACTUATION

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

---

J

ff

a)

.%).

S\

CA

/

UrVi

—

^

CB

The illustration above shows the hydraul ic panels.
The letters and nomenclature listed below iden
tify the parts of the hydraulic system in the

schematic diagram at the end of this section.

C

A Control Panel

CB Main Panel

CC Stop and Dress Control Panel
CD Sump
CE Pump
CF Safety ValYe
CG Filter
CH Hydraulic Motor

Cl Wheel Feed Cylinder
CJ Dresser Feed Cylinder
CK Lead Control Cylinder
CL Pressure Switch Cylinder
CM

Lubricating Pump Actuating Cylinder

CN Backlash Compensator Cylinder

The hydraulic system is self scavenging.
A few strokes of the machine table in rapid
traverse will dispose of air or vapor which

may have accumulated during shipment or
during repair work.

The pump CE is of the orifice controlled
variable delivery type. This kind of pump is
also.named back pressure controlled variable
delivery type. It delivers only the amount of

hydraulic fluid necessary to perform the re



quired operation. The pressure developed
depends on the resistance encountered. The
safety valve CF prevents excessive operating
pressures.

The Control Panel CA contains:
CR Left Direction Plunger

CS Left Remote Plunger
CT Feed Plunger
CU Stop Plunger
CV Rapid Plunger
CW Right Direction Plunger
CX Right Remote Plunger

The Main Panel CB contains:
DA Direction Flow Control Valve

DB Orifice Selecting Valve
DC Booster Plunger
DD Control Pressure Valve

DE Accessory Pressure Valve

DF Accessory Valve

DG Direction Key
DH Manual Direction Control Valve

DI

Manual Start - Stop Valve
Feed Left Orifice

DJ

Rapid Traverse Orifice

DK
DL Feed Right Orifice



601

HYDRAULIC ACTUATION

The Stop and Dress Control Panel CC contains:
DQ Actuating Plunger

DR Selecting Valve
DS Stop and Dress Control Valve

DT

Stop After Dress Valve

DU Manual Dresser Start and Feed Valve

The Start After Dress Valve DV is furnish
ed as optional equipment. It is solenoid oper
ated.

In the schematic

circuit diagram, hydraulic

lines within the solid borderlines are in drilled

and cored openings in the panels. The lines
between panels CA and CB are in a self-con
tained manifold assembly. Each end of this
assembly is bolted to the rear of one of the
panels. With the exception of the lines con
necting the pump CE, other hydraulic lines
shown outside the panels are within the ma
chine base and table assembly.

There

are four pressure systems in the

circuit. These are pump pressure, pump con
trol pressure, accessory pressure and panel
pressure.

PUMP PRESSURE AND PUMP CONTROL
PRESSURE: The pump delivers fluid into the
main pressure line EA. During operation, the
pressure in this line depends on the resistance
encountered by the hydraulic motor CH. The
pressure may rise to the setting of the safety

valve CF, which is not adjustable and is set at
the factory to 1100 to 1200 pounds per square

inch.

The pump pressure may be checked by

inserting a pressure gage in the fitting on the

filter.

When the machine table is stopped, the
pressure in the main pressure line EA equals
the pressure in the pump control line EB which

is approximately 150 pounds per square inch.
During operation, pressure is maintained in
the pump control line EB by the return flow
from the motor.

ACCESSORY PRESSURE: The pressure in

line EC is maintained by the adjustable valve

DE.

The valve DE is controlled by the adjust
ing screw locked by cap nut BP. Pressure in
line EC is used in the stop and dress control
panel CC, the wheel feed cylinder Cl, the
dresser feed cylinder CJ, the lead control
cylinder CK, the lubricating pump actuating

cylinder CM and the backlash compensator
cylinder CN.

PANEL PRESSURE: Pressure is main

tained in line ED by the adjustable valve DD.
This is done thru the pressure exerted by the
adjusting screw locked by the cap nut BO.
The line ED supplies fluid to the panel CA for



actuating the direction flow control valve DA



and the orifice selecting valve DB in the main

panel CB.







MOTOR CONTROL: Motor CH is controlled
from the direction flow control valve DA and
the orifice selecting valve DB. These two
valves are positioned by plungers CR, CT, CU,
CV and CW. Some of these plungers are hy
draulically interlocked. Depressing one of

the interlocked plungers will reset the mating

plunger. The interlocked plungers include the
two direction plungers CR and CW, the feed

plunger CT and rapid plunger CV. The plung
ers CR, CT, CU, CV and CW are of the two



position type. With the plungers arranged
vertically the two positions are up and down.
Valves DA and DB are of the three position

type and are arranged horizontally, from front

to back. Therefore, the three valve positions

are rear, center and front.

For right hand threads the position of the

valves and plungers are shown on page 603.

The speed of the motor is determined by
the delivery of the pump. During rapid trav
erse, extra high motor speeds can be obtained
by the rapid traverse connection through line
EE.

PUMP DELIVERY CONTROL: The deliv
ery of the pump is controlled by the pressure
in line EB.

While the hydraulic motor is operating,
line EB is connected to the motor return flow
line. The connection is made through the

branch line EG which is permanently connected
to the motor return line EH. According to the

setting of the orifice selecting valve DB the

motor return line EH



feed left orifice DJ, the rapid traverse orifice
DK or the feed right orifice DL.

During the stop position the pump control

line EB is connected through the branch line

is

connected either to the

El to the pump pressure line EA. While the











602

HYDRAULIC ACTUATION

DA

Rear*

Rear*
Center
Center
Front*
Front*
Center
Center

Valve

DB
Center
Rear
Center
Rear
Center
Front
Center

Front

CR
Down
Down
Down
Down

Up
Up
Up
Up

TABLE OPERATION

Rapid to left
Feed to left
Rapid stop to left
Feed stop to left
Rapid to right
Feed to right (shown)
Rapid stop to right
Feed stop to right

♦These positions are opposite for left hand threads.

Position

CT

Down

Up

Down

Up

Down

Up

Down

Plunger

CU

Up
Up

Down

Down

Up

Up
Down
Down

CV

Down

Up

Down

Up

CW

UpUp
Up
Up
Up

Down Down

Up

Down

Up

Down

Down

Down

machine is stopped, a maximum pressure of

approximately 150 lb. is maintained.

MANUAL DIRECTION CONTROL is ob

tained by shifting valve DH with the manual

table direction control knob 17. Valve DH is
of the spring centered three position type. At
the two end positions plungers CR and CW are
shifted by the hydraulic connections.to plungers

CS and CX.

MANUAL START AND STOP is obtained
with a lever engaging the plunger of valve DI.
Valve DI is hydraulically interlocked with the
stop plunger CU. Shifting one of these plungers

causes shifting of the mating plunger.

AUTOMATIC STOPPING

is obtained by de
pressing stop plunger CU, which is done by the
stop dog on the table. Automatic stopping can

also be obtained by the action of the stop and

dress control panel CC.

AUTOMATIC STARTING after dressing is

obtained by shifting valve D V. This valve is fur

nished as extra standard equipment. It is
normally spring retained in the disconnect
position. At the end of the dressing cycle it is
shifted to the pressure connect position by the
action of a momentarily energized solenoid.

THE STOP AND DRESS CONTROL func
tions as follows: At the last roughing cut
actuating plunger DQ is shifted. (This is done
by the action of cam roller 20h engaging stop
and dress cam 20g on the wheel feed control

assembly 20.) This connects one of the direc^
tion lines EM or EN through lines EO or ED
to one end of the spool plunger DW, shifting



the plunger to the opposite end. At the next
reversal of the machine table the pressure is
connected into line EQ, causing plunger DX to
be shifted. This will reverse the pressure
connections in lines ER and ES. This will
actuate the dresser feed cylinder CJ and the

pressure switch cylinder CL. The dresser
feed cylinder CJ feeds the dresser toward the
wheel. It also feeds the wheel toward the work.
The pressure switch cylinder CL starts the
wheel dresser on the dressing cycle. Because

of the pressure connection through the restric



tion ET the large plunger DY is gradually

moved up forcing through the engagement with

plunger DZ plunger DX to the upward position.
This will reset both the dresser feed cylinder
CJ and the dresser switch cylinder CL. After

dressing, the machine is either started manu
ally or by the action of valve DV. At the end of



the next table stroke, which also is the end of
the finish cut, valve DT is shifted which will
stop the machine.

As soon as

that cam roller 20his disengaged from the stop



and dress cam 20g) the valve DQ is shifted to

its original position causing the resetting of
all the valves in the stop and dress control

the hand wheel is turned (so

panel CC.





HYDRAULIC SERVICE

All fitting parts in the control panel are

carefully inspected during assembly. Before

a machine is shipped it is tested under severe
operating conditions for a long period of time.

603

HYDRAULIC ACTUATION

If a plunger should fail to function it is rea

sonably certain that the trouble is caused by

impurities in the hydraulic fluid. The cause of
failure should be removed without changing cne
size of the part. All plungers have closely
lapped fits. If a plunger should not operate

because of too little clearance it must be

corrected by removal of the most minute

amount of stock. Such amounts are measurable

only in ten-thousandths of an inch.

The importance of keeping any foreign
matter out of the hydraulic system cannot be
over emphasized. The greatest care must be

used. Before reassembly, parts must be
washed in clean gasoline or in cleaning fluid
and must be dried thoroughly. It is absolutely

essential that everything be perfectly clean.

If a gasket is replaced, it must be as

certained, before reassembly, that no hole in
the new gasket is missing and that there is no

other opening that may cause a leak.

SNAP ACTION: If the panel is to work
satisfactorily the control plungers must move
freely. The best way to determine whether or
not these plungers are sliding freely is to
check the snap action. Only free sliding plung
ers have good snap action. The snap action is
checked by depressing one plunger a short
distance, then observing the resetting of the
mating plunger to the upward position and
finally the snapping down of the partly de
pressed plunger to the downward position.

Hydraulically interlocked" plungers

are:

the left and right direction plungers CR and

CW,

the feed and rapid plunger CT and CV and
finally, the stop plunger CU and the manual
start and stop valve DI.

The direction flow control valve DA

and

the orifice selecting valve DB should be checked
for free movement of the plungers'only after
every other possible cause of failure has been
eliminated. If the direction flow control valve
is sticky the machine will not start, stop and

reverse accurately. If the orifice selecting
valve DB is not moving freely the machine is

sluggish in going into feedafter rapid traverse.

REMOVING VALVE PLUNGERS:

If the

action of the machine indicates that one of the

valves is sticky the following information will



assist in removing the plungers.

The plungers of the accessory valve DF,
the manual direction control valve DH and the
manual start - stop valve DI are removable
after the plate bolted to the top on the rear of
the main panel CB is taken off.

For removing other plungers

the respective

panel has to be taken out of the machine.

The control panel CA may be removed
after taking out a socket head screw and a tube
fitting from the inside of the base and three
socket head screws at the front of the panel.

The socket head screw and the tube fitting are
accessible through the opening below the ma

chine table at the left side of the base.

To remove the main panel CB it is neces

sary to take off the machine table, disconnect



all piping and tube connections leading to the
panel, and remove three socket head screws
at front.

To remove the stop and dress control panel
CC the various tubes leading to the panel have

to be disconnected and three socket head screws
at the front of the panel taken out. The tube

connections are accessible after panel R is re
moved as described on pages 206 and 207.



However, if the machine table
this work is done the tubes inside the base

maybe disconnected without removing panel R.



MANUAL DIRECTION CONTROL: If the

is

removed while

direction knob 17 is forced with excessive
pressure to one of the end positions the actuat
ing pin BU may be sheared off. To replace

this pin it is necessary to remove the manual

control assembly by taking out four fillister
head screws from the flange of the support
bushing.

17

MANUAL START-

STOP CONTROL:

The manual start-

stop control actuat
ed with lever 19 is
constructed the same
as the manual direc

tion control and its
actuating pin may be

replaced in the same
manner.

7





MANUAL

DIRECTION CONTROL









BU

604

HYDRAULIC MACHINE ACTUATION

CA

{

La

t

\\\\

\

L

\

\
\

\
\

\
\
\
\

CB

®

w

T

a

\ \ \ \ \

pcrcr

Pr

3

Trfe

®

o

I

TL

/v /CU

1

( I

i

r

}

®

EX-CELL-O
PRECISION THREAD GRINDERS

®

cw

o

MACHINE SET FOR RIGHT
HAND

m

''o

CV

V

\ \ \ \ '•

&

SCHEMATIC HYDRAULIC DIAGRAM

STYLES 35 AND 35-L

POSITION SHOWN:

FEED TO RIGHT

EXTERNAL THREAD

PUMP PRESSURE
PUMP CONTROL PRESSURE r~~
ACCESSORY PRESSURE
PANEL CONTROL PRESSURES

EXHAUST
DRAIN__

/EA

COLOR KEY

____

1

3

[

c

]

CL CJ

n

,CM

~^L

§1

a

\

\

CN

cx

i,

iz

N

r

c

Cl

CD

605

DRESSERS,

ATTACHMENTS AND EQUIPMENT

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

THREE WAY 60° AND 29° FORM DRESSER

a Flexible drive shaft cable
b Control switch
c Lever actuating slide
d Lever operating rod
e Diamond locking screw

f Diamond dressing tools

g Graduated diamond adjusting screw

THREE WAY 60° AND 2 9° FORM DRESSER:
This Dresser is adjustable for straight line
thread forms such as American National, 60°
Sharp “V” and 29° Acme. The dresser sup
ports the dressing diamonds in individual piv
oting levers. Each lever is provided with dia
mond locking and graduated diamond adjusting
screws. The three levers are actuated from
a common slide. The levers are supported by
the base brackets. The two side brackets are
adjustable for either 2 9° or 60° Form Threads.

h Pivot lever

i Base brackets
j Thread angle adjusting screw
k Thread angle setting graduations

1 Thread angle locking screw
m Collars to adjust length of stroke





To prevent any loss of time during the
dressing operation, the reversal and the stop
positions are adjustable
form by means of two collars, which are locked
to the rod operating the electric control switch.

THREE WAY, PLATE-TYPE 10° to 90°

FORM DRESSER: This dresser is adjustable
for straight line thread forms such as Ameri
can National, 60° Sharp “V”
ified Buttress and variations of these forms.

to

the required thread

, 290 Acme, Mod




701

DRESSERS, ATTACHMENTS AND EQUIPMENT

4

THREE WAY, PLATE-TYPE 10° TO 90° FORM DRESSER

a

Lever
Lever operating rod

actuating slide

b

c

Graduated diamond adjusting

screw

d

Diamond dressing tools

e

Diamond locking screw

The dressing diamonds are supported in
individual pivoting levers. Each lever is pro
vided with diamond-locking and graduated

diamond-adjusting screws. The three levers
are actuatedfrom a common slide. The levers
are supported by the base brackets. The two
side brackets are adjustable between 5 and 45

degrees.

For efficiency during the dressing opera
tion the reversal and stop positions maybe ad
justed to the minimum movement necessary
for the required thread form. This adjust

ment is made by positioning two pins which

actuate the control switch.

THREE WAY CRADLE-TYPE 10° to 90°
FORM DRESSER: This Dresser is adjustable
for straight line thread forms such as American

f Base brackets
g Thread angle locking screw
h Thread angle setting graduations

i Pivot lever
j Pins to adjust length of stroke
k Control switch

National,
fied Buttress threads.



individual pivoting levers. Each lever is pro
vided with diamond adjusting and locking

60° Sharp “V”

,29° Acme, and Modi

The dresser supports three diamonds in

screws. To facilitate the accurate adjustment

of the width of the thread form, the diamond in
the center lever is carried in a micrometer

adjustable sleeve. Low price natural stone



diamonds are used.




The brackets supporting the pivot levers
at both sides are adjustable, allowing a dress
ing path anywhere within 5 to 45 degrees toward

the sides of the grinding wheel.

The
of

dresser is adjustable for the position

the thread form. This adjustment is re

quired on some machines to correct the taper









702

DRESSERS, ATTACHMENTS AND EQUIPMENT

b

THREE WAY, CRADLE-TYPE 10° TO 90° FORM DRESSER

a Flexible drive shaft cable
b Control switch

c Lever actuating slide

d Diamond locking screw

e Micrometer adjustable sleeve
f Dresser diamonds
g Pivot lever
h Angularly adjustable base bracket

setting. A suitable graduation, coinciding with
the angle of the taper on one side, is provided.
There are also graduations to simplify the an- .
gular and the helix settings.

To prevent loss of time during the dressing
operation, the reversal and the stop positions
are adjustable to the required thread form.
This is accomplished by means of two adjust



able pins actuating the control switch.

UNIVERSAL CAM-TYPE DRESSER: This
dresser is adjustable for straight as well as

radius
60° Sharp “V”

form

threads

, such as

American

National

, 29° Acme, Whitworth, Modified

Buttress, and special forms.

i Helix setting graduation
j Helix clamp
k Thread angle setting graduations

1 Thread form setting graduations
m Dresser base
n Thread form setting lock disc
o Rods to adjust length of dressing stroke
p Cradle

The various forms are obtained by the use

of

interchangeable cams. One set of two 60°
cams is used for all the common American
National Form and 60° Sharp “V” threads.

UNIVERSAL CAM-TYPE DRESSER

703

DRESSERS, ATTACHMENTS AND EQUIPMENT

Another set of two 29° cams is required if
Acme Threads are

to

be

ground. For Whitworth

or other radius forms, it is necessary to have
a different set of cams for each particular form
desired. Cams can be supplied to grind threads

of any symmetrical form that is not less than
14-1/2° on the side. Modified Buttress and
unsymmetrical special forms can be dressed

with less than 14-1/2° on one side. Cams for

standard form threads will be furnished as
ordered. A set of cams may be interchanged
on the machine in about twenty minutes' time.

Further information on the Universal Cam-

Type Dresser will be found in section 800.

INTERNAL STRAIGHT LINE DRESSER:
This dresser together with the stop bracket
FA is mounted in place of the tailstock on the
machine table.

INTERNAL STRAIGHT LINE DRESSER

The stop bracket, mounted between the
dresser and the headstock, permits the dresser
to be moved so that it is kept free of any inter
ference with large chucks during the grinding



FE

FA

W'

o

EM

o

FJ

FL

FK

FH

f

i

I

I
i

ift

'!

11

i >!

i!

i

! >!'

i

HI

I

\

\

\

I

/

Fl

M

\

i

s

I

I

l

I

'

704

INTERNAL STRAIGHT LINE DRESSER

DRESSERS, ATTACHMENTS AND EQUIPMENT

operation,

and allows the dresser to be posi-

tioned again for dressing.

The dresser unit should be

placed far enough
to the right of the work to provide sufficient
space for gaging between the work and the
wheel. After it is positioned, it is clamped to

the table with the handle FB.

After the dresser is mounted, it is aligned

with the point on the grinding wheel,

To re-

position the machine table for subsequent
dressings, the stop FC at the extreme right of
the table is adjusted so that it registers on the
dial of the indicator FD that is located at the

right end of machine base.

The wheel is dressed with one diamond

is swung

to both sides of the wheel. Two stops

that

FE are provided for positioning the diamond
bracket or holder to the proper form angle.

For setting these stops, the knurled hand knob

FF is loosened and the graduated disc rotated
until the desired angle for one side of the wheel
is reached. The stop screw is adjusted and
locked to that position, and the same adjust

ment for the thread angle setting is made on
the other side. For setting the dresser to an

angular position, it is necessary only to move

the dresser bracket toward one of the stops

and then lock it in that position.

To dress the wheel, the diamond

.

is

swiveled

past the wheel with the handle FG. To get the
correct width of flat at the top, it is necessary
to have the diamond set correctly in the holder

FH. To accomplish this, the wheel should be

dressed at all three points, both sides and the

flat. A piece of thin sheet brass or steel

is

fed
by hand into the wheel to make a small template
of

the wheel shape. This template can be put

into the comparator to check the width of the
flat. If the flat is too wide, the diamond should
be fed toward the wheel a small amount by

means of the threaded screw FI. The wheel

should be dressed again. The process should

be repeated until the required wheel form is

obtained. No further adjustment is necessary

until sufficient wear of the diamond has oc

curred to require a second setting.

wheel into the diamond the amount that is to

be dressed off the wheel. This method assures
the correct work size.

The size setting is obtained by setting the
slide FJ with the graduated knurled knob FK.
Example: If the wheel has been dressed, a
finish cut been taken, and the hole is found to
be .001" small, the dresser slide should be

moved .0005" as shown on the graduated knob.
The wheel is dressed after it has been fed into
the diamond and then the work piece can be
finish ground. This should produce the correct

size.

While grinding to the same size setting, no
further adjustments need to be made. If it is
found necessary to remove the top slide FJ for

any reason,
justed against the permanent stop before re

moving the slide. When the slide is returned

for wheel dressing and moved against this stop,

it will be automatically located in the same po
sition in relation to the wheel. If it is found
necessary to remove



machine, the permanent stop bracket FA should
be left on the dovetail slide to provide a locat
ing point when the dressing unit is remounted.

INTERNAL PANTOGRAPH-TYPE DRESS

the stop screw FL should be ad-

the entire unit from the

ER: This dresser is adjustable for straight as

well as radius

National, 60° Sharp “V”
Modified Buttress and special forms.

For generating the desired thread form, a

set of two interchangeable cams is required.

form threads, such as American

, 29° Acme, Whitworth,











' ■ K

After the correct

wheel form has been ob
tained, the dresser may be set in relation to
the work so that for further wheel dressing, it
is necessary only to feed the cross slide and



internal pantograph-type dresser

in grinding position

705

DRESSERS, ATTACHMENTS AND EQUIPMENT

INTERNAL PANTOGRAPH-TYPE DRESSER In dressing position

One set of 60° cams is used for the American
National Form and 60° Sharp “V” threads,
while another set of cams is required if Acme
threads are to be ground. For Whitworth or
other radius forms, it is necessary to have a
different set of cams for each thread form.
Cams can be supplied to grind threads of any
unsymmetrical form that is not less than 5° on
the side. A set of cams can be changed on the
machine in about five minutes.

Two select natural stone diamonds are used
in the Internal Pantograph-type Dresser. The
radius on the radius form threads does not de
pend on a special radius form lapped on the
diamond but is generated by means of a point
on the diamond. This point is “

while dressing,

change in the thread form due to wear.

The

dresser is hinged to the external grind
ing spindle. During grinding it is swung up
ward 90° and locked in position out of the path
of the work and workhead.

The diamonds are positioned by the adjust

ing screws and locked in place with two set

eliminating

resharpened

the possibility of a

-:7

screws. The diamond setting is facilitated by

means of a step block. Because of the re
quired alignment of the diamonds, setting is
more important for radius thread forms than
for straight line thread forms.



”






The use of an adjusting knob at the right of
the dresser allows the adjustment of the desired
width of thread form. The graduated knurled
knob at the front of the dresser is for adjusting

the depth of the dressing cut.

The movement of the diamonds is
with a manually operated pantograph mechan

ism. Straight line form cams are used. The
desired accuracy of thread form is readily ob
tained because of the large reduction between
the cams and thread form.

INTERNAL THREAD GRINDING ATTACH

MENT: A separate unit that can be attached to
the front of the wheel slide
cial equipment for grinding internal threads.
This unit consists of the grinding spindle FO,

spindle bracket FP, idler pulley FS, a counter
pulley FU, a two-step pulley FW for the motor,
a V-belt FV and flat belt FT.

if

'•

is

available as spe

"7

controlled










706

DRESSERS, ATTACHMENTS AND EQUIPMENT

INTERNAL THREAD GRINDING ATTACHMENT

The internal grinding head is attached to

the front of the wheel cradle and held in place

by four cap screws. The key FQ in the bottom

of the head is used for alignment. Before at
taching the internal grinding spindle, the small

WHEEL SLIDE CRADLE

Jri.

i

Y

FO

FP

FQ

FR FT

FS

piece of felt that covers the oil hole in
dle during shipment must be removed.



In the top center of the spindle head is an
Allen screw, used to position the spindle FO
lengthwise. When the spindle is placed in the

WHEEL MOTOR

¥

FU

FV

the spin

J

FW



7

l

A

is

INTERNAL THREAD GRINDING ATTACHMENT

707

DRESSERS, ATTACHMENTS AND EQUIPMENT

head, the hole that is drilled in the top of the
spindle must be brought into alignment with
this screw. After the spindle is engaged with
the alignment screw, the two screws FR hold
ing the spindle in the head must be locked.
These screws must be tight enough to hold the
spindle rigid. However, any excessive pres-

of these screws may damage the spindle

sure
bearings.

When the whole internal grinding assembly
has been correctly installed, the center of
grinding wheel face will be in line with the
center of rotation of the wheel cradle, thereby
maintaining the wheel on the center of the work
regardless of the helix setting of the wheel

head.

After the spindle head has been locked in

position, the motor pulley, the counter pulley
and the idler pulley should be attached. The
counter pulley shaft should be slid back for
tension on the flat belt and secured with the
bolt. The belt tension can be adjusted with the

idler pulley. The V-belt tension can be ad

justed by sliding the spindle driving motor

lengthwise.

When the belts have been adjusted, the
guard that fits over the wheel spindle pulley
and the guard over the belt from the motor
should be replaced. The motor belt guard is
the same guard as used for external grinding.

In the table below is tabulated the length of
thread that can be ground with the internal
grinding attachment. The length indicated may
be reduced on work pieces with excessively
large helix angles because of the possibility of

interference between the threaded hole in the

work piece and the grinding quill.



adjustments and work size compensation. Dia



monds that are no longer suitable for use in
the dresser can be used in the wheel thinning

WHEEL THINNING ATTACHMENT

attachment.

When a thread must be ground close to a
shoulder the form on the wheel is dressed off
center and the excess width removed. This
equalizes the wear on dresser diamonds.
Either side of the wheel may be thinned. The
dressing diamond is held in a pivoting arm for
accurate movement. The attachment has a
base which clamps to the table ways and a
bracket that can be adjusted to suit the wheel
diameter. The depth of the wheel thinning cut
is controlled manually by the wheel feed con

trol.





THREAD DIAMETER LENGTH OF THREAD

1" to 1-5/8

1-5/8

” to 3

3

” to 8

” . . .

”
”

2"

2-1/2 ”

3

”

WHEEL THINNING ATTACHMENT: Thin
ning the grinding wheel to suit the individual
thread form prolongs the service life

of dresser
diamonds by reducing the amount of wheel grit
removed at each dressing. Since there is less
diamond wear fewer replacements are neces
sary and less time is consumed for diamond

708

OIL COOLING UNIT: The Refrigerator
Type Oil Cooling Unit permits maintaining
closer overall lead tolerances, especially on
long work pieces. The unit is driven by a
thermostatically controlled 3/4 hp electric

motor. Together with the coolant motor and



the coolant tank, it forms an independent unit
placed outside the base of the thread grinder.
The electrical connections are obtained with
plugs and receptacles. A large size flexible
hose connects the supply line. The unit is



furnished complete with thermometer.

DRESSERS, ATTACHMENTS AND EQUIPMENT

REFRIGERATOR TYPE OIL COOLING UNIT

SUCTION HOOD: To prevent the diffuse-

ment of coolant vapor, the Ex-Cell-O Thread

Grinder may be equipped with a vapor hood.

The hood has an inbuilt motor-driven ven-
tura fan and an oil reclaiming filter. It pre
vents vapor accumulations around the machine

caused by the high operating speed of the grind
ing wheel.

The suction hood filter should be cleaned

every three to six months, depending on the

amount of use. The circular sheet metai guard

at the rear of the cradle must be taken off be
fore the filter can be removed. While the hood

is at the rear the filter can be taken out of the
bottom of the unit. This can be done after four
screws are

removed from the sides of the

iron retainer. The filter should be washed in

kerosene or cleaning fluid and blown out with

an air hose.





angle



The fan is driven by a single phase 1/20 hp
1725 rpm electric motor. The hood is suspend
ed on rollers operating on a trackway to facil
itate changing the grinding wheel, setting the

dresser, and adjusting the diamonds.

... .

V

l

\

SUCTION HOOD





TABLE TYPE RELIEVING ATTACHMENT

RELIEVING ATTACHMENT,TABLE TYPE: >
The table type relieving attachment permits
quick conversion from standard thread grind
ing to eccentrically relieved grinding. Taps
and straight fluted thread hobs (a no lead
attachment is required for hobs) can be ground
at high operating speeds. The attachment is
held in position on the work table by four
socket head screws GO, GP, GQ and GR.

It is driven from gear GL which is mounted to
the work spindle. The relieving movement is
obtained by a single lobe cam driven by change



709

DRESSERS, ATTACHMENTS AND EQUIPMENT

r **31

TABLE TYPE RELIEVING ATTACHMENT

gears.

The change gears are arranged in the

change gear compartment GG according to the
number of flutes on the work. Gears are fur
nished for relieving straight fluted hobs or taps

with 2, 3, 4, 5, 6, 8, 10, 12, 14 and 16 flutes.

The amount of relief is adjustable. The at
tachment accommodates a maximum work
length of 21 inches and a maximum diameter of

5 inches. The maximum length of thread that
can be ground from the headstock end is 14

inches. For threads that do not require re

lieving, the mechanism is made inoperative.

The attachment is regularly furnished with

the “

Plain Eccentric Type Cam”, allowing up

to .010" relief for taps with American National,

Whitworth, British Association and Metric

Threads. A “
Acme taps and a “

Con-eccentric Type Cam

Quick Return Type Cam” for

” for

straight fluted thread milling hobs are avail
able as extra standard equipment.

OPERATION: The drive gear GL is bolted
to the work spindle. It drives gear GF. Gear
GF drives the live center through gear GE and

rotates the drive shaft GM. Shaft GM drives
the change gears in the gear compartment GG

it the opposite end.

The release mechanism is actuated from
the adjusting shaft GB. It maintains contact
between the cam and the cam follower. It also
serves to disconnect the relieving movement
for concentric grinding. This is done by rais
ing the table GA above the point of engagement

with the cam GN. A 180° movement of the ad
justing shaft GB is required for engaging or

disengaging the cam GN.







The dial on shaft GC is set to the desired

amount of relief which is adjustable from 0 to
.125".

Shaft GD engages the table release plug

which is used for disengaging the table when

new cams are

installed. At the inner position
of shaft GD the spring pressure for the re
lieving movement is applied. At the outer po
sition the table may be lifted open as shown.

erated. The tension on the spring is adjusted
by turning the knurled knob GH. Lever GJ on
top of the tailstock withdraws the center from
the work. The tailstock center is aligned with
the headstock center by adjusting screw GI



which has a graduated dial.

ATTACHMENT: The relieving movement must
be timed in relation to the work rotation. It
starts while the grinding wheel is at the max
imum distance from the work.

tailstock center quill GK is spring op

The

SETTING THE TABLE TYPE RELIEVING

At this time the follower engages the low

position on either the Plain Eccentric Type or
the Quick Return Type Cam. On the Con-

eccentric Type Cam the follower engages the
dwell position adjacent to the start of the rise.



This position can be found by jogging the work
spindle, or by turning the cam shaft with a










710

DRESSERS, ATTACHMENTS AND EQUIPMENT

wrench while the gears are temporarily disen

gaged. With the maximum distance between

the wheel and the work thus established, the
part is put between the centers. The work
drive dog should be in place, but not tightened.
The work is rotated until the cutting edge, or

the point from which the relieving movement is

to start, is toward the grinding wheel. The
work drive dog is then tightened.

A thread with a land area can be ground

at one setting with the “

STANDARD 16 PITCH GEARS

POSITION

DRIVE SHAFT
CAM SHAFT

Con-eccentric Type

CHANGE GEAR INFORMATION FOR

TA8LE TYPE RELIEVING ATTACHMENT

NUMBER OF TEETH

MAX.

70
51

MIN.

23
23



Cam”. If the “
“

Quick Return Type Cam

must first be finish ground concentrically to
the correct pitch diameter. The attachment is
set for concentric grinding by raising the table

off the cam with the release mechanism which

is operated with shaft GB.
reached the table is lowered to engage

Plain Eccentric Type

” is used, the work

When size is

Then the grinding is continued with the relieving

attachment in operation and the work piece is

relieved until the desired land is obtained.

CENTER OF IDLER
STUD MUST BE
WITHIN THIS AREA

” or the

the

cam.

3

]

16

CAM SHAFT

4

DRIVE

SHAFT

l

r

711

DRESSERS, ATTACHMENTS AND EQUIPMENT

The “

Plain Eccentric Type Cam

” is sym

metrical and therefore is used in the same po

sition for both right and

“

Con-eccentric Type

Type Cam

” must be assembled to conform to

left

hand threads. The

” or the “

Quick Return

the direction of the relieving movement. Mark

ings on the cams show which way they are to

be mounted.

CHANGE GEARS: Gears with 24, 28, 32,
40, 48, 56 and 64 teeth are regularly shipped
with the attachment. The outside diameter
permitting, each gear may be mounted in any
position.

The shaft GM turns three times as fast as
the work spindle. The number of flutes are
obtained by positioning the gears as shown in

the chart below.

Number

of

Flutes

2

3

4

5

6

8

10

12

14

16

POSITION AND NUMBER OF GEAR

TEETH_____________

Drive Shaft

32

64
64

40

64
64
64
64
64
64

Idler

40

32/24

24
48
40

28/56
24/40
32/48
32/56
28/56

Cam Shaft

48
48
48
24

32

48

32

24
24
24

CHANGE GEARS FOR SPIRAL FLUTED
WORK: The ratio for the change gear compart
ment varies for work with right or left hand
lead on the thread form.

For right hand lead

the desired ratio =

n(l - T/L)

3






In determining the gears for the change

ratio the structural limitations of the change

gear compartment must be considered. The

figure with chart on page 711 indicates the max
imum and minimum size gears which can be

mounted on the cam shaft GS and on the drive
shaft GM. Outlined also is the space within
which the idler gear must be located.

TAPER RESULTING FROM INCORRECT

CHANGE GEAR RATIO: It is not always pos
sible to find the exact ratio desired. There
are two ways to meet the condition.

If the work piece is not already manufac
tured it may be possible to change either the
diameter or the angle of the gash.

If no change in design is possible and gears

of a different ratio are used, a taper will re
sult. This is due to the variation in timing
which causes the start of the relieving move

ment to be varied in relation to the flutes

(gash) on the work piece. If the taper is not
too large it may be corrected by the use of the
taper grinding device. For practical reasons
it is desired to keep the taper within .0001" or

at the most within .0002" included taper per

inch.

The approximate taper on the work due to

variation in the change gear ratio is calculated

as follows:

Included taper = -



A = number of thread leads on work piece
B = relief on work

Ax Bx Dx

2160

C

(approximate)

C = angle in degrees at center of

closing part of periphery which is uti
lized for relieving movement

D = variation between desired ratio and

change gear ratio











cam en-



For left hand lead
the desired ratio =

In the above equations:

n

b

number of flutes
T = lead of thread form
L r lead of flutes or gash

712

n(l + T/L)

-----

j

Example: A single thread, right hand work
piece with 16 flutes, 3.25" long has a thread
lead of .330" and a gash lead of 242.12 ". The
relief on the work is .125". A cam with 5/6
rise and 1 /6 return is used. The approximate
taper obtained with a convenient gear setup is

to be determined.

DRESSERS, ATTACHMENTS AND EQUIPMENT

Desired ratio =

16(1 -.330/242.12)

3

5.326064

Selected was a gear set up of:

Drive shaft
Cam shaft

.........................

.........................

Idler ....................................

Change gear ratio =

70 x 42

24 x 23
A = 3.250/.330 = 9.848485
B = .125

C =

360 x 5

6

= 300

. . 70 teeth
. . 23 teeth

24/42 teeth

= 5.326086

D = 5.326086 - 5.326064 = .000022

Therefore, the approximate taper per inch

equals:
AxBxDx2160

C

_ 9.

848485x. 12 5x. 000022x2160

300

Approximate included taper per inch = .000195"

STRAIGHT FLUTED THREAD HOBS must

be designed to provide clearance for the grind

ing wheel. With the width of the gash half the

distance between cutting edges as shown in

the

drawing, the chart gives minimum hob diam

eters on which .030" relief is possible for

various numbers of flutes. If, for a given
number of flutes, the outside diameter is less
than that shown in the chart, the grinding wheel

will cut into the cutting edge of the next tooth.
Thus the amount of relief must be reduced in
proportion to the diameter to avoid wheel in

terference.

Chart of minimum hob diameters on which
.030" relief is possible with number of flutes
shown. Straight fluted hobs only.

Number

of Flutes

Hob Diameter

3

4
6

8

10
12
14
16

Example: The chart shows that for .030"

relief a 14 flute hob must have an outside di-

ameter of at least 4-3/4". If the outside
diameter is only 4 inches the relief cannot be

more than .030 x 4

4.75

= .025





RELIEVING
TYPE

: With this attachment, the grinding spin

ATTACHMENT, SPINDLE

dle is mounted in an eccentric sleeve which is
oscillated to move the grinding wheel toward
and away from the work. A cam, driven by

gears from the work spindle, actuates the ec

centric sleeve through shafts and linkages.

Minimum

.250
.4375

1.000

1.625

2.500

3.500

4.750

6.250







TOTAL RELIEF

A lever at the left of the work head is used
to engage or disengage the cam follower from
the cam, thus connecting or disconnecting the
attachment. A knurled knob on the front of the

wheel cradle is loosened to allow the eccentric
sleeve to oscillate for the relieving movement.
When relief is not required, the knurled knob

is locked, engaging a locating pin which pre



vents movement of the eccentric sleeve.

The cam is set so that it will start re
lieving at the proper point by loosening the re
tainer nut for the two clamps holding the cam,
and turning the cam either way until the relief
starts at the desired place. The retaining nut
should then be tightened. The drag link con
necting the cam roller arm and the guide rail

in the slot can then be adjusted for the amount

i

of relief.






713

DRESSERS, ATTACHMENTS AND EQUIPMENT

..

is

'

& W&

• I

■ ■w'.

:

m $ ’

i

QUICK CLAMP TYPE INDEX HEAD: The
index head facilitates quick, accurate grinding
of

multiple start threaded pieces. The head is

regularly equipped with an index plate for

grinding 2, 3, 4 and 6 start threads. It is

mounted to the face of the work spindle nose.

Four selector plates are furnished. The

desired selector plate is assembled directly

on the index plate, and covers the slots not
being used. When work with only two starts is

ground, the selector plate with only two slots

is used. This prevents the lock pin from enter
ing any of the other slots.

r

"

—|

%

QUICK CLAMP TYPE INDEX HEAD

M :

i i

m U

I

A

' j:

&

w

>:-I

l

: V ■

Additional index plates and selector plates
can be furnished to suit individual require
ments.

TABLE EXTENSION WITH
work table extension and tailstock can be fur
nished to accommodate work to 72 " length on
the Style 35 Grinder, and to 90" length on the

Style 35-L Grinder. The extension reduces the

\

maximum swing to approximately 11 inches. A
steadyrest is usually required to support the
longer work and prevent deflection.

TAILSTOCK:

4

S-

5V



-

CAM GRINDER



A



Operation: The operator pulls the operating

lever which disengages the lock pin from the

slot in the index plate. The work can then be

turned until the lock pin drops into the next

slot. The work is then in position for grinding

the next start of the thread.

TABLE EXTENSION WITH TAILSTOCK

CAM GRINDER FOR UNIVERSAL DRESS
ER CAMS: Although cams for the Universal
Dresser are obtainable from Ex-Cell-O at any
time, a Cam Grinder
producing all cams from large size, straight
form templates in the customer's plant.

is

available for accurately

I



714

DRESSERS, ATTACHMENTS AND EQUIPMENT

GRINDING WHEEL BALANCING STAND

GRINDING WHEEL BALANCING STAND:
To get a good grinding finish it is necessary to
have a balanced wheel. The stand shown facil

itates the balancing operation. It is furnished
complete with two inbuilt liquid levels and the
balancing arbor.

The motor mounting is adjustable to maintain
proper belt tension.

The grinding wheel is 3 " in diameter and
3/8 " wide. It can be used
eter of 2 M

.

to

a

minimum diam

The wheel is dressed by a diamond tool

which projects from the slide support for the
dressing operation, and is withdrawn during

grinding. The diamond tool is positioned in
the tool holder by a set screw, and held in the
adjusted position by a locking screw. A knurled
screw locks the tool holder in position in the
slide support. The dressing is done by passing
the wheel across the diamond.

A good grade of spindle oil should be used
in the oil cup provided to lubricate the spindle
bearings.



BENCH TYPE LEAD PICK-UP FIXTURE:

The bench type lead pick-up fixture allows the

operator to match the thread on pre-cut work

and adjust the work driving dog to one work
piece while another piece is being ground.



Before the grinding wheels are balanced it

is necessary to level the stand by means of the

adjusting screws. The balancing arbor is in

serted into the wheel adapter and the assembly
is placed on the stand. Then the two balancing

weights are moved in the adapter groove until

the static balance is obtained.

HEADSTOCK CENTER GRINDING AT
TACHMENT: With this attachment headstock
centers can be kept smooth and true. A base
bracket clamps to the tailstock ways of the

machine table. A feed slide is held firmly, but
not rigidly, to this bracket by two hold-down

bolts with T-nuts. This slide is moved toward

the headstock center by a hexagon head feed
screw retained in a block that is held rigidly
to the base bracket.

The grinding spindle and the electric drive
motor are mounted on a dovetail slide that is
actuated by,a hand crank to pass the grinding

wheel across the headstock center. The attach

ment is so designed that grinding at the correct
angle is assured. A 1/4 hp, 10,000 rpm motor
drives the grinding spindle through a V-belt.



To set the fixture to new work, the lead is
first picked up approximately on the thread
grinder, and the work driving dog set at this
position. Then, with the indicator slide with
drawn, the work is put between the centers of
the fixture and the indicator support bracket is
positioned until the pick-up finger properly
contacts the thread. A screw under the indi



cator slide provides adjustment to the work
diameter. For the fine adjustment, the thumb
screw on

dial turned until the pointer is at the zero

position.

the indicator is loosened, and the



BENCH TYPE LEAD PICK-UP FIXTURE





715

DRESSERS, ATTACHMENTS AND EQUIPMENT

With the fixture set up in this way, subse
quent pieces will be exact duplicates of the first
when, with the dog resting against the stop, the
indicator shows zero.

Three sizes of fixture are available for
work sizes as follows:

to 3" diameter, 8" maximum length

to 6" diameter, 18" maximum length

to 8" diameter, 33" maximum length

CENTER LAPPING MACHINE: On close ,
tolerance machining operations it is necessary
that the female work centers be in line, be
round and that the center angles conform to the
angles on headstock and tailstock centers. Dis
tortion from heat treating and inaccuracies of

rough centers must be corrected. Work cen

ters can be conditioned quickly on theEx-Cell-

O Precision Center Lapping Machine.

The base column of this machine supports

a precision ball bearing spindle and its elec
tric drive motor. The vertical movement of



r

i




P

r •

1

i

•)

'

t

\

ip

t

I

i

i

*

!

the spindle is con
trolled by a hand lever.

Counter-weights pro
vide sensitivity to lap
ping pressure.

Standard abrasive

stones and pencil
wheels are used. A
diam

ond

dresser

mounted on the spindle
bracket conditions the

stone at the correct

angle. The dresser is

swung out of the way

during lapping.

A wide range of

work diameters and

lengths can be con

ditioned on this ma

chine. The work rest

with a male center is



EX-CELL-0 STYLE 74

CENTER LAPPING

MACHINE

adjustable to any po

sition on the vertical

ways of the column.











OTHER ATTACHMENTS AND EQUIPMENT

CAMS, FOR UNIVERSAL CAM-TYPE DRES
SER

SETTING FIXTURE, FOR UNIVERSAL DRES
SER DIAMONDS

DIRECT-CURRENT WHEEL SPINDLE DRIVE
DIRECT -CURRENT MOTOR
ATTACHMENT

FOR AUTOMATICALLY

GENERATOR

SET

STARTING MACHINE AFTER DRESSING

RELIEVING CAMS

For spindle-type relieving attachment

FACE PLATE

10" diameter with four T-slots

INDEPENDENT FOUR-TAW CHUCK

8" diameter semi-steel body with adapter

to fit work spindle

STEAD YRE RTS

Both table mounted and table extension
mounted,

EXTRA POSITIONING ARMS FOR STEADY

RESTS

EXTRA

REMOVABLE GUIDE BUSHINGS FOR

STEADY RESTS

EXTRA LEAD PICK-UP FINGERS



HEADSTOCK CENTER



Tool steel
TAILSTOCK-CENTER, HIGH SPEED STEEL
TAILSTOCK CENTER, CARBIDE TIPPED

EXTERNAL WHEEL SPINDLE

Without wheel adapter and pulleys

WHEEL ADAPTER
CAMS FOR INTERNAL PANTOGRAPH-TYPE

DRESSER

CAM FOLLOWER FOR INTERNAL PANTO

GRAPH-TYPE DRESSER

INTERNAL WHEEL SPINDLE, 12,500 RPM
INTERNAL

3/4" dia x 1-7/8" long

1-1/2" dia x 1-7/8" long

QUILLS

For wheels with 1/4" holes

LEAD CHANGE GEARS

EXTRA PARTS AND ASSEMBLIES

GRINDING WHEELS



716

UNIVERSAL CAM-TYPE DRESSER

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

■-

?

GENERAL DESCRIPTION

THE UNIVERSAL CAM-TYPE DRESSER:

may be used to obtain both straight and radius
thread forms such as American National, 60°
Sharp “V”

tress and Special forms.

The various forms are obtained by the use of

interchangeable cams. One set of two ‘ ‘ 60° cadis

is used for all the common American National

and 60° Sharp “V” threads. Another set of two

“

29° cams

be

ground. For Whitworth or other radius forms,
it is necessary to have a different set of
for each particular form desired. Cams can be
supplied to grind threads of any symmetrical
form that is not less than 14-1/2° on the side.
Modified
forms can be dressed with 7-1/2° on one side.

, 29° Acme, Whitworth, Modified But

” is required if Acme threads are to

cams

Buttress and unsymmetrical special

Cams for standard form threads will be fur

nished as ordered. A set of cams can be changed

on the machine in about twenty minutes.



The above thread forms are obtained with two
select natural stone diamonds, carried in the
dresser. The thread form does not depend on a

”

special radius form lapped on the diamond. The
radius on the thread forms is generated by the
point of the diamond. This point is constantly
“

resharpened

ing change of the thread form due to diamond

” as it dresses the wheel,

wear.

The Universal Cam-type Dresser consists of
the base bracket, the swivel bracket, the carriage
and the removable cover. It is mounted on the
dresser slide at the rear of the grinding wheel.

eliminat





- 1 -

A. Removable Cover
B.

Cover Hold Down Knobs

C. Coolant Hose

D. Coolant Manifold

E. Carriage
F.

Diamond Tool Carriers
G. Diamond Lock Screws
H. Diamond Dressing Tools
I. Swivel Bracket
J. Base Bracket
K. Bolt Slot

L. Electric Power Line

UNIVERSAL CAM-TYPE DRESSER

M. Half Round Shields
N. Flexible Drive Shaft Cable

UNIVERSAL CAM-TYPE DRESSER, WHEEL SIDE

The base bracket supports the swivel bracket

which is adjustable either normal to the axis or

normal to the helix of the work. The setting is

facilitatedby the vertical angle adjustment gradu

ation. After the desired setting is obtained the

swivel bracket is locked by means of the swivel

bracketlock screws. The

non-rotating lead screw
is supported at the upper ends of the swivel brack
et.

The lead screw support permits endwise
movement during reversal of the rotation of the
nut. This allows the dresser to be adjusted for

various widths of thread form. This adjustment

is made with a graduated thread width control
knob on the swivel bracket The base bracket is

supported on the dresser slide. The thread form
is positioned in relation to the axis of the work

by swiveling the base bracket with the horizontal

angle and adjustment screws. These screws

ac-

tuate a pinion which engages the horizontal ad-

justment graduation plate. The base bracket is
locked to the desired position by means of studs

which extend through the bolt slots on the side



of the base bracket, anchoring it to the dresser

slide.

-

The dresser is motor driven through twoVee
belt step pulleys and a flexible drive shaft which
is enclosed in a metal hose to prevent wear due

to dirt and lack of oil. The drive shaft is packed
in grease. The motor is equipped with a solenoid

brake to prevent coasting. It is indirectly con

trolled by the two limit switches which are mounted
on the carriage. These limit switches are ac
tuated by the cam cycle and control the stopping
and reversing of the dresser drive motor through
overload protected magnetic switches.

The flexible drive shaft is mounted to the

power drive connection. The power drive may

be readily disconnected by unscrewing the retain

ing nut as the power drive connection.






2

UNIVERSAL CAM-TYPE DRESSER

O. Power Drive Connection
P. Dresser Cams
Q. Non Rotating Lead Screw

R. Graduated Knob to Con

trol Width of Thread

Form

S. Vertical Angle Adjust

ment Graduation

T.

Horizontal Adjustment

Graduation

U. Spanner Wrenches for

Cam Lock-Nuts and
Switch Controls

V. Horizontal Angle Adjust

ment Screws

W.

Swivel

Bracket Lock

Screws
X. Reversing Switch
Y Stop Switch

Z Graduated Diamond Set

ting Screws

AA

. Graduated Cam Follower

Adjusting Screws

AB. Drive Bracket









UNIVERSAL CAM-TYPE DRESSER, POWER DRIVE SIDE

The removable cover fits over the two dres

ser cams,

the

cam followers and the two diamond
tool carriers. It is held on the carriage by means
of two hold down knobs. The cover keeps out
dust, dirt and undesirable oil. It also protects
the cams and cam followers. The hold down knobs
position the coolant manifold which is connected
to the oil coolant system supplying oil for clean
ing the two diamond tool carriers.

In the carriage are two half round shields
which protect the side of the cams. They are
located in slots from which they are easily re
moved by turning 180 , thus giving ample room







The grinding wheel is dressed by two move
ments of the diamonds. The first of these move
ments is perpendicular to the axis of the grinding

wheel. The length of the second or crosswise
movement is adjustable for controlling the width
of the thread form.

When the diamond dressing tools are being
installed, the “
of

the distance from the points of the diamonds

Diamond Setting’’ or

the

adjustment

to the front faces of the diamond tool carriers is
facilitated by the graduated diamond setting

screws.

The diamonds are clamped in the ad

justed position with the diamond lock screws.

for removing the cams.

The relation of the two

The carriage is retained on a non-rotating with the

graduated cam follower adjusting screws,

diamonds

is

controlled

lead screw on the swivel bracket. The carriage The path of the diamonds may be adjusted for
supports the dresser drive mechanism and the alignment at the front of the wheel as is neces-

two diamond dressing tools in the diamond tool sary when the wheel is being dressed for radius

carriers.

thread forms.







3

UNIVERSAL CAM-TYPE DRESSER

UNIVERSAL CAM-TYPE DRESSER—Front

AC. Screw Plugged Oil Hole
AD.
AE.

Wedge
Oil

Cup

Blocks

AF. Cam notches in line with carriage face

AG. Screw Plugged Oil Holes
AH. Etched Line for centering carriage

AI. Dresser Bracket Cap
AJ. Cam Retaining Nuts

LUBRICATION

There are four lubrication points on the Uni

versal Cam-type Dresser.

The oil cupAE on the dresser carriage should with light machine oil whenever cams are changed

be filled with 600W oil every other day. The
screw plugged oil hole AC on the drive bracket
should be filled monthly with 600W oil. On the



swivel bracket bosses are the screw plugged oil
holes AG which should be filled with spindle oil
once each week. The lead screw should be oiled

and

the cam faces should be kept well greased.
The drive shaft cable is packed in grease and
needs no attention.

4

UNIVERSAL CAM-TYPE DRESSER

CHANGING CAMS

(Refer to illustrations

on

pages 2, 4, 5.)

1. To change the cams on the Universal Dresser,
the hold down knobs B and the coolant mani
fold D must be removed. The cover A

should

be lifted off and the two half round shields

M removed. The dresser is jogged with the
start and stop control until the notches in the
faces of the cams are in line with the top of
the carriage as shown at AF.

2.

The diamond carriers must be pulled back
to clear the cams. The wedge blocks AD are
inserted.

3. Cam retaining nuts AJ are loosened with the
spanner wrench which is furnished with the
dresser.

4. Cap AI must be removed from the dresser
bracket.

-—R

mm

o'



purities the lead screw is inserted into the
support and checked for free movement

11. The carriage is placed on the cradle. While
it is supported with one hand the lead screw
is inserted. If accurately shaped thread forms
are to be produced it is of vital importance
that no jerk movement is caused. Therefore
the screw must slide freely at each operating
position.

12. Thread width control knob R must be turned

clockwise until it seats.

13. With lead screw and cams assembled, the

dresser carriage should be centered between
the lead screw bearings. To center the car
riage

the

dresser is started with the electric

control and run until the carriage reaches the

R. Thread Form Width

Control Knob

AK. Lead Screw Tail



-AL

AK

—

i

l—-f —

LTJ-|----tS J

II >1

_

J

\~>-

i

5. Thread form width control knob R should be
turned counter clockwise until dimension
AL is one half inch or more.

6. The carriage must be moved so that lead

screw tail AK is accessible at the outward
position as indicated in the drawing.

7. Lead screw tail AK must be turned counter
clockwise to remove lead screw.

8. With the lead screw out, the cam retaining
nuts AJ

9. The

washers and cams should be removed.

new cams must be assembled in the cor
rect right and left positions, cam washers
and nuts replaced but not tightened.

10. The lead screw support in the carriage must
be

thoroughly

cleaned and greased with a good

grade of vaseline. For ascertaining that no

binding is caused by abrasives or other im-

AL. Dimension

line AH while moving toward the left. If the

carriage is already too far to the left, the
dresser is run toward the right until it is
beyond the center. Stopping and starting it

again will reverse the carriage toward the
left The dresser may now be stopped as it



central position.

reaches the line

AH

which marks the correct

14. Cam notches should be set in line with the
carriage face as shown at AF and cam re
taining nuts tightened. (Caution: The



retaining nuts must be tightened with a fair
clamping pressure

but no excessive force

should be exerted.)

15. Cam faces should be greased, wedge blocks
removed, half round shields and cover as

sembled. Cam followers should be let down
gently by hand to avoid damaging the



cam



cams.

5

AM. Grinding Wheel

AN. Lock Screws

Cams

AO.

Distance

AP.

to support body
Cam Follower Adjusting

AQ

Screws

AR. Diamond Setting Screws

Step Block

AS

of

cam follower

UNIVERSAL CAM-TYPE DRESSER

m

•c

AS

m

m

AN

AO

t

AP—'

AM

AN

AO

r—AP

I

AQ

ADJUSTING OR REPLACING DIAMONDS

1. The dresser must be moved back to provide
the necessary clearances from the wheel.

2. Lock screw AN must be loosened, the worn
diamond removed and a new one inserted. The

diamond must be adjusted to the required
length with the diamond setting screws AR.
The diamond setting may be simplified with a
small step block (not furnished). The correct
diamond setting is marked on the side of the
cams. The diamonds may be set within .001
to. 003" of their correct position by this meth
od. A Diamond Tool Setting Fixture to faci
litate diamond setting is described on page

10.

3. The lock screw AN must be tight before the
machine is started.

4. The thread form width control knob R must be
turned clockwise .005" to .006" to increase
the width of the form on the wheel. Each

It may be ordered as extra standard

equipment.

AQ

AR

”




graduation on the dial of the knob represents
.001

” on the width of the wheel.

The cam follower adjusting screws AQ must

5.
be adjusted so that the distance AP from the

front of the cam follower to the support body

is about 1/4". The dresser should be returned

slowly toward the wheel.

As the dresser approaches the wheel it should

6.

be run through its cycle. During the cycle,
one

of

the diamonds will touch the wheel and

the other will not. The diamond that touches

should be moved back by turning its cam fol
lower adjusting screw AQ clockwise until both
diamonds touch the tip of the wheel during the
cycle. The diamond setting screws AR should
not be used as adjusting screws after the
diamonds are set and locked with screws

The thread form control knob R should be

7.

turned counterwise not more than .0003" per
cycle of the dresser until the diamonds cut
on the sides of the wheel.



AN.

6

UNIVERSAL CAM-TYPE DRESSER

THREAD FORM CORRECTIONS

Angles and radii on thread forms are deter

mined by the shape of the cams. The

thread form

all the adjustments for alignment of the diamonds



are made with the cam follower adjusting screws
may be positioned with relation to the work by and not with the diamond setting screws,
swiveling the base bracket.

Note: After the dresser is set up and is in

for dressing the grinding wheel repeatedly, forms may be corrected:

use

V

V

V

v

\__

LEFT \

\

NO. 1

\

v

\

!/

ff

!/

/

7

RIGHT

7

7

/

1. FORM OUT OF STEP.

This condition may be corrected by moving

back the diamond which is too far ahead. The

cam follower adjusting screw AQ on the side
to

be

corrected must be turned in a clock

wise direction.

\

A

IN

LEFT \\

NO. 2

\

\

\

\

/>

/>

L

A

/

/

/

o

RIGHT

2. FORM TOO WIDE.
The thread form width may be decreased by
turning thread form width control knob R
counter-clockwise.

The following illustrations show how thread

W

\>

NO. 4

\>

V

LEFT X

V

v

\'

\

/

/

7

7

/

/

4. IRREGULAR RADIUS AT THE ROOT.



This is caused by chipped or worn diamonds.

The damaged diamond must be replaced.

Y

V

V

NO. 5

\r^

V

LEFT

V

V

\>

\

\

5. RADII OF FORM INCORRECT.
This is caused by a broken diamond or a dia
mond

worn too much for sharpening on wheel

to

correct. A new diamond must be installed.

vvX EXISTING H
v V HALF ANGLE

\

\

DESIRED

HALF

xx ANGLE

LEFT

\

i\

/

/

/

/

/

/

NO. 6 /

/i

//

I / RIGHT

/

/

/

/

zzj

RIGHT

/

/

/

RIGHT

/

A



RIGHT

3. FORM TOO NARROW.

Thread form width maybe increased by turn

ing thread form width control knob R clock

wise.

6. THREAD ANGLE TOO WIDE.
Small errors may be corrected by tipping the

dresser in the circular way provided for helix

angle setting. The correction angle can be
found from the following formula:

Tangent of Existing



Cosine of Correction Angle - Tangent of De



Half

Half Angle

7

Angle

sired

\

\

\

LEFT

s

|A

\

\

NO. 7

UNIVERSAL CAM-TYPE DRESSER

/

/

/

A

!/ RIGHT

A

1

c

\

/

\

PIVOT CENTER

7. THREAD ANGLE CORRECT BUT NOT CEN
TERED.

The dresser must be relocated around its pivot
center as shown.

CARE OF DIAMONDS

The cams used with Ex-Cell-0 Universal
Dresser for form thread grinding are designed
to

sharpen the diamonds and will maintain a uni

form radius on the diamond tip
able care.

To obtain maximum diamond life:

1. The amount dressed off the wheel should be

as little as necessary to hold the form. On
straight thread forms .001*

meter is usually sufficient. On radius forms

the amount re moved must never exceed. 0005
on the wheel diameter.

2.

The wheel should never be dressed with the

coolant pump disconnected. Coolant keeps
diamonds clean and prevents overheating which
might cause diamonds to become loose in the

holders.

if

used with reason

1 on the wheel dia

the



5"

Indicator reading = 5 x tangent A

DIAMOND SPECIFICATIONS






11

Suitable diamonds for the Universal Cam-type
Dresser may be ordered from Ex-Cell-0 Corpor
ation. The diamond number should be specified.

Diamond No. 48-4105 ... For straight thread

forms

Diamond No. 48-4128

....For Whitworth and

other radius form

threads

For special forms, diamonds of the
specification or number as furnished originally

should be ordered.

Diamonds for radius thread forms must have
a sharp point. Diamonds purchased from other
sources must be checked in the projector before
they are mounted. If the point should be inside

the .002

11

radius line the diamond must be re-

jected as unsuitable.

same



SATISFACTORY

DIAMOND POINT

.002"

RADIUS LINE
(BORDERLINE BETWEEN
SATISFACTORY AND UN



SATISFACTORY DIAMOND)
UNSATISFACTORY

DIAMOND POINT

8

UNIVERSAL CAM-TYPE DRESSER

DIAMOND TOOLS FOR

EX-CELL-O UNIVERSAL CAM-TYPE DRESSER

DIAMOND TOOLS FOR RADIUS FORM THREADS
No. 48-4128

ETCH LINE AND LETTERS

TOP

90° TO 100°

\

38°-3°

000

ill

— 001

ENLARGED VIEW

w

.002 POINT MUST BE

CENTRAL WITH AXIS
WITHIN .001 AS
SHOWN IN THIS VIEW

-OCTOHEDRON SHAPE
DIAMOND TIP

SMOOTH FINISH

SHANK C.R.S

r

I

CYANIDE CASE

.010 DEEP

FULL SIZE VIEW

.3

745

+ .000

001

DIAMOND TOOLS FOR STRAIGHT LINE FORM THREADS
No. 48-4105

I

— 380-3*

7

ENLARGED VIEW

/

60°

1/2 OF INCLUDED ANGLE_L5°

\

■

n

OCTOHEDRON SHAPE DIAMOND POINT MUST BE

CONCENTRIC WITH .3745 DIAMETER SHANK WITHIN .003

SMOOTH FINISH

CYANIDE CASE

.010 DEEP

FULL SIZE VIEW

SHANK C.R.S.

70° TO 100°

i

.3745i'ooi

SHARP POINT DESIRED

MUST NOT EXCEED .010 RADIUS

9

UNIVERSAL CAM-TYPE DRESSER

SETTING FIXTURE FOR UNIVERSAL DRESSER DIAMONDS

By the use of this Ex-Cell-0 fixture new This minimizes the possibility of the diamond point
diamonds may be readily adjusted on the projector being chipped. The fixture may be purchased as
without touching the diamond point at any time, extra standard equipment.

-AY

r-r

IS

n

1 >

i

i

v

i

i

i

I

1

I

i

—

m

SETTING FIXTURE WITH SIZING PIN AND DIAMOND

AT.

Required Setting Height

AU.

Sizing

AV. Diamond Tool

The Diamond is set in the following manner:
The sizing pin AU is adjusted either with a height
gage or with a sizing block. The height AT is ad

justed so that

setting, which is stamped on the Universal Dres
ser Cam. The diamond tool AV is inserted and
the fixture placed on the projector. The diamond
is turned slowly until the smallest angle AZ is
obtained. It is set to the same height as pin AU
and screw

it

conforms to the desired diamond

AX is tightened slightly. The diamond

Pin

AZ. Smallest Angle on Diamond

DIAMONDS WITH COLLARS MOUNTED IN DIAMOND TOOL CARRIERS

AW. Diamond Tool Collar

AX. Locking Screw
AY. Set Screw

is adjusted exactly to the correct height with set
screw AY and locked with screw AX. The collar



AW is slipped over the diamond shank, fitted

snugly against the fixture base and locked in po



sition. The diamond AV and collar AW are then
removed from the fixture and inserted into the

arm on the Universal Dresser. Both diamonds

are set in the same manner, assuring their lo
cation in proper relation to each other and to the
center of the grinding wheel.





10

THREAD GRINDING AND GRINDING WHEELS

EX-CELL-0 PRECISION THREAD GRINDERS

STYLES 35 and 35-L

Good

thread

the correct thread grinding wheel,
suitable coolant,
maintenance of wheel and work

surface speeds,

proper dressing, and

grinding depends primarily on:

correct depth of grinding cuts.

For some work, good thread grinding also

depends on:

work centers,
work drive dogs and
steadyrest

Thread grinding differs from dther kinds
of grinding. The results obtained are at times
contrary to what was expected. Operators
experienced in other kinds of grinding do well
to familiarize themselves with the rules of
thread grinding.

GRINDING WHEELS:

Thread grinding
wheels are divided generally into two groups
according to the bonding material used to hold

the abrasive. The two types of wheels are
resinoid and vitrified.

The RESINOID wheel is tough, fast cutting

and stands a good deal of abuse. It is generally

used in production work, and in the softer

grades, is sometimes used on precision work.

The VITRIFIED wheel, because of its stiffer
structure, is generally used to grind pre-cut
threads since it has less tendency to deflect
and follow lead error,

It is also used for
radius form threads and precision work in
general.

WHEEL SPEED: A speed of approximately

9,000 surface feet per minute is recommended
for resinoid wheels and approximately 7,000
surface feet per minute for vitrified wheels.

The test tag attached to each wheel showing the
testing speed and the safe operating speed

should be consulted. The safe operating speed

should never be exceeded. The wheel surface

speed should be maintained by increasing the
grinding wheel speed as the wheel wears down.
A chart at the end of this section shows the
rpm to be used as the* diameter of the wheel
decreases, in order to maintain the surface
speed.

THE GRIT SIZE is the size of the abrasive
grain in the wheel. Sizes range from coarse
to fine. Coarse grit wheels hold the form

better and cut the metal faster than fine grit
wheels. Therefore the use of coarse grit

wheels is desirable. However, the coarseness
is limited by the width of the root on the
form, and by the hardness and cutting qualities
of

the work piece.

WORK SPEEDS: Thread grinding is divided

into two established methods:

1. Heavy cuts at low work surface speeds

of 18 to 100 inches per minute.

2. Light cuts at high work surface speeds

of 100 to 300 inches per minute.

If the work surface speed is too high in

relation to the wheel speed the wheel will

wear excessively. If the work surface speed

is too low in relation to the wheel speed the
wheelwillbecome glazed. At the correctspeed
the particles loosen and fall out of the wheel
when they become worn.

As the work is changed from one thread
diameter to another the work speed also should
be changed so that the proper surface speed

may be maintained.

Work speed charts showing the rpm at
which the work must be driven for the desired

surface speeds are included at the end of this

section.

COOLANT: The stream of coolant oil must
hit the wheel at the point where it is grinding
the work. The coolant must flow in sufficient
volume. An excessive amount of coolant is
never harmful but insufficient and incorrectly

thread

901

THREAD GRINDING AND GRINDING WHEELS

applied coolant is frequently the cause of
trouble.

The main purpose of coolant is to dissipate
heat as it is generated at the contact between
the wheel and the work. The thin section near
the point of the wheel especially must be pro
tected from severe heat accumulations.

DRESSING AND DRESSING DIAMONDS: In
thread grinding it is hardly possible to over
emphasize

the necessity of dressing at frequent
intervals. The frequency of dressing depends
on the performance of the grinding wheel and

the limits required on the work piece and es
pecially the accuracy of the thread form de

sired on the work piece. All wheel particles

do not loosen and fall out of the wheel when
they become worn. Such particles cause the
wheel to become glazed, rub the work and
generate excessive heat. To remove such

particles and restore the thread form the

grinding wheel must be dressed at suitable

intervals. The new particles exposed will

cut clean without causing undue heat.

The amount dressed off of the wheel should

be as little as necessary. A depth of .001" on

the wheel diameter is usually sufficient.

Dressing feed should not exceed .001" per

revolution.

The coolant valve should be opened

slightly

during dressing. A small flow of coolantkeeps

the diamonds clean and prevents overheating.
Overheating might cause diamonds to become

loose in the holders.

The diamonds must be sharp and in good
condition. A dull diamond produces a dull
cutting surface on the wheel. Frequent turn
ing to engage the wheel with a sharp diamond
edge will help distribute wear and increase

diamond life. Sharp diamonds cut quietly with

a low pitched sound. Dull diamonds produce
a loud, high pitched tone.

Additional

dressing diamond economies
are possible by the use of the wheel thinning
attachment which is described in the “

700

section of this book.

Diamonds must be supported firmly. This
requires firm setting of the diamond point and
firm clamping of the diamond. The finish on

the work will show chatter marks if the diamond
is not supported rigidly.



Diamonds mustbe reset if worn excessively

or if the setting is accidentally ground away.

A small diamond will not absorb a large
amount of heat and is much more likely to
fracture than a larger one.



Brown diamonds are used for dressing.
These diamonds are very tough. The blueish
white diamonds usually used in jewelry
very brittle. For this reason they are
suitable for dressing.




DEPTH OF GRINDING CUTS: The number

of

roughing and finishing cuts that are neces

sary depends upon the material, nature and

precision requirements of the job.

The approximate depth of the ordinary

roughing cut is from .020" to .040".

When two or more cuts are taken it is

generally advisable to take from a minimum of

.0015" to a maximum of .004" depth of cut for
the last finish cut.

During continuous grinding no finish cut of

less than .0008" on diameter should be taken.

Otherwise most wheels will have a tendency to
load and will produce a coarse finish.

It is usually advantageous to grind threads
not exceeding three inches in length produc
tively from solid unthreaded blanks as coarse
as:

10 pitch, up to 7/8" diameter
12 pitch, up to 1" diameter



be more economically produced when
are rough threaded previous to hardening.

13 pitch, up to 2 " diameter
16 pitch, up to 3-1/2" diameter

Threads

coarser than 10 pitcjh can usually

On most jobs a cut of .020" to .040" deep

(on a side) can betaken in one pass. On threads

having a greater depth, more than one cut will

”

have to be taken.

In some cases, two or even more cuts are

advisable, even on the shallow threads, where

extreme accuracy in lead, diameter, and finish

are required.

are
un-

the blanks





902

THREAD GRINDING AND GRINDING WHEELS

When grinding to finish size in one cut,
for example, a 20 pitch thread (having a depth
of .032"), a work surface speed from 18 to 24
inches per minute can generally be used.

In grinding deeper threads having a depth

.040

over

always

to .040

” where more than one cut is nearly

advisable, the roughing cuts (from. 020"

” deep) can usually be taken at a work

surface speed from 36 to 48 inches per minute,

while the finish cut (from .0015" to .004

” deep)

can usually betaken with a work surface speed

from 72 to 96 inches per minute.

On large production, especially of work

which is difficult to grind due to severe ma-

chineability conditions, it is economical to
rough and finish grind in separate operations.
This allows the use of a coarser wheel for the
rough grinding operation.

BALANCING GRINDING WHEELS: A good
grinding finish can only be obtained with a
balanced wheel. Wheels may get out of balance
during use. The out of balance area of the
wheel may be located close to the periphery,

when the wheel is new. As soon as the out of
balance area is worn away rebalancing is re
quired in order to compensate for the changed

conditions.

The adapters used on all Ex-Cell-O ex
ternal thread grinding wheels have two adjust
ably mounted balancing weights. These weights
allow adjusting any out of balance condition
quickly and conveniently. For this purpose the

grinding wheel together with the adapter is
removed from the grinding spindle. After the
adapter with the wheel is placed on a suitable
arbor and a pair of horizontal strips the two
balancing weights are shifted toward the light

side. After the most suitable position is found
the weights are locked securely to prevent

slipping during grinding.

Balancing equipment made especially for
balancing wheels used in this machine is shown
and described in the attachment section (“700

section) of this book.

LONG

PARTS:

THIN, PRECISION THREADED

The previous recommendations for

wheel speeds, work speeds, and depth of cut

are good for most of the work. The only

ex-

ception is long, thin precision threaded parts

such as lead and feed screws requiring ex
tremely close limits. After all precautions
are taken such as maintaining the coolant at
room temperatures and providing the neces
sary steadyrests, it is desirable to reduce
wheel and work surface speeds. These speeds

have been reduced advantageously to as low as
50% of the normal operating speed. Both
speeds must be reduced in the same relation.
Experience has proved that depth of cuts may

be taken which double the production otherwise

obtainable on this type of work by the use of
the necessary light cuts.

WORK CENTERS: To prevent out of round

and eccentrically ground work, the centers in

the piece must:

1.

Be in line with each other,

2.

Have the same angles as the tail-

stock and headstock centers,

3.

Be clean and

4. Be well lubricated.



The first three requirements may be ob
tained conveniently on the Ex-Cell-0 Center
Lapping Machine. This machine is indispensa
ble equipment for hardened, centered and
ground steel parts.

WORK DRIVE DOGS must be securely

fastened and must be in perpendicular engage



ment with the work driver. Otherwise the



driving forces exerted will affect the position

ing of the work piece.

Furthermore, for two way grinding as

commonly used on thread grinding machines,

the work drive dog must slide freely into the

driver without being forced and with a minimum

of

end play.

STEADY REST: A work piece may be
ground accurately only if it is properly sup
ported and cannot be deflected either by the
action of the grinding wheel or by its own

weight

”

MATERIAL: For high precision limits,

such as required on micrometer and instru

ment adjusting screws, materials must be
selected that stay put after the machining oper
ation and do not creep. For such purposes
carbon alloy steels containing nickel, tungsten
and molybdenum are desirable, while steels

containing vanadium are undesirable.



















903

THREAD GRINDING AND GRINDING WHEELS

If difficulties of this kind are encountered
a new test piece from a different material
should be processed and compared with the
original work piece. Such a test piece should

have the most desirable heat treatment which
may include seasoning after rough grinding for
some materials.

GRINDING SUGGESTIONS: The grinding
wheel should notbe used after it has worn down

to 13 " diameter.

The proper wheel should be selected for the

work in accordance with the wheel manufac
turers' recommendations.

The wheel should operate at the correct

speed to suit the wheel diameter.

The proper work speed should be selected.
Grinding cuts of recommended depth should

be taken.

The coolant tank should be filled to the top

of the highest baffle with the proper coolant.

Suitable wheels used at the correct speeds,

with the correct work speeds and a suitable

coolant will operate with very little heat gen
erated. Only a few sparks should be visible
in the coolant stream during grinding.

CORRECTING UNSATISFACTORY GRINDING

a. Burning:

An ample amount of coolant must hit the
contact area formed by the point of the wheel
and the work.

In rough grinding much burning can be

eliminated by using a coarser dressing feed or
a somewhat heavier dressing cut to open the
pores of the wheel and make it cut more freely.

Reduction in work speed may eliminate

burning, but failing to do so the original speed

should again be restored.

A grinding wheel of a softer grade or with

a more open structure may eliminate burning.

A lighter cut will always reduce burning.
Of course this is at the expense of production
because more passes are required. Therefore
a lighter cut should be used only as a tem
porary expedient

b. Unsatisfactory finish:

Diamond lines are evenly spaced. If objec

tionable, they can be eliminated or reduced.



This is done by using a slower diamond feed
or lighter cut when the wheel is dressed es
pecially on the final pass.

Surface roughness is usually caused by a
too heavy cut or too high work speed on the
finishing pass.

Erratic scratches can be caused by dirty
grinding oil. They can be eliminated by clean
ing the coolant tank.



THREAD GRINDING WHEEL RECOMMEN

DATIONS: The wheels listed will generally

perform satisfactorily for the pitches and on
the types of metal for which they are recom
mended. Plants that do a variety of small lot
work do not need to stock as many wheels as

the list indicates. By changing wheel and work

speeds and the depth of cut, it is possible to
use any one of the wheels with fairly good re

sults for a wider range of pitches and materials.

On long production runs, for best results,

it is advisable to consult the nearest repre
sentative of the wheel manufacturer.

In the following list of wheels, the type of

bond is indicated as follows:

(Res.) for Resinoid
(ViU for Vitrified















904

THREAD GRINDING AND GRINDING WHEELS

WHEELS FOR GRINDING EXTERNAL THREADS

AMERICAN

NATIONAL FORM THREADS

TOOL AND HIGH SPEED STEELS, hardened

COMMERCIAL THREADS

Threads per Inch

8 to 12

13 to 20
24 to 36
40 to 60
60 and finer

Carborundum

100-4-T (Res.)
120-4-T (Res.)
150-4-T (Res.)

220-4-T (Res.)

220-4-T (Res.)

PRECISION THREADS

8 to 12

13 to 20

24 to 36
40 and finer

100-N-T (Vit.)

120-N-T (Vit.)
150-N-T (Vit.)
280-N-T3 (Vit.)

ALLOY STEELS, heat treated and hardened.

COMMERCIAL

8 to 12
13 to 20
24 to 36

THREADS

120F2-A310 (Res.)
150F2-A310 (Res.)
180F2-A310 (Res.)

Norton

100-S9TH (Res.)
100-S9TH (Res.)
150-T9TH (Res.)
180-T9TH (Res.)
220-T9TH (Res.)

38120-J7BE (Vit.)
38150-K8BE (Vit.)
38220-

MlOBE (Vit.)

Macklin

100-10E20-2 (Res.)
100-10E20-2 (Res.)

150-10E20-2 (Res.)
180-10E20-2 (Res.)
220-10E20-2 (Res.)

320-09T (Res.)

100-S9TH
150-T9TH (Res.)
180-T9TH (Res.)

(Res.)

100-10E20-2 (Res.)

100-10E20-2 (Res.)
150-10E20-2 (Res.)

ACME AND WORM THREADS

TOOL AND ALLOY STEELS, heat treated and hardened.

2 to 4

5 to 10

12 to 18

60-P-T (Vit.)

80-P-T (Vit.)

100-

P-T (Vit.)

3880-I8BE (Vit.)
38120-J7BE (Vit.)
38150-K8BE (Vit)

WHEELS FOR GRINDING TAPS

AMERICAN NATIONAL FORM THREADS

HIGH SPEED STEEL

COMMERCIAL THREADS

Threads per Inch

4 to 7

8 to 12
13 to 20
24 to 36

40 and finer

Carborundum

80-4-T (Res.)
100-4-T (Res.)
120-4-T (Res.)
180-4-T (Res.)
220-4-T (Res.)

100-S9TH (Res.)
100-S9TH (Res.)
150-T9TH (Res.)

180-T9TH (Res.)
220-T9TH (Res.)

PRECISION THREADS

4 to 7
8 to 12

13 to 20

24 to 36

40 to 56

64 to 80

80-P-T (Vit.)

100-N-T (Vit.)

150-N-T-(Vit)
220-N-T-(Vit.)
280-N-T3 (Vit.)
280-N-T3 (Vit)

38120-J7BE (Vit)
38120-J7BE (Vit)
38150-D8BE (Vit)

38180-M10BE (Vit.)

38220-

Norton

Ml OBE (Vit.)

320-09T (Res.)

Macklin

80-10E20-2 (Res.)
100-10E20-2 (Res.)
120-10E20-2 (Res.)
180-10E20-2 (Res.)
220-10E20-2 (Res.)

220-10E20-2 (Res.)

905

THREAD GRINDING AND GRINDING WHEELS

WHEELS FOR GRINDING TAPS (Cont'd)

AMERICAN NATIONAL PIPE THREADS

HIGH SPEED STEEL

Threads per Inch

8 to 11-1/2

Carborundum

100-4-T (Res.)

or 100-N-T2 (Vit.)

Norton

100-S9TH (Res.)

Macklln

100-10E20-2 (Res.)

14 to 18

120-4-T (Res.)

or 120-N-T2 (Vit)

27 and finer

150-4-T (Res.)

or 150-N-T2 (Vit)

ACME THREADS

HIGH SPEED STEEL

2 to 4

15 to 10

12 to 10

60- P-T (Vit.)

80-P-T (Vit)

100-P-T (Vit)

WHEELS FOR GRINDING INTERNAL THREADS

AMERICAN NATIONAL FORM THREADS

TOOL AND ALLOY STEELS

For Grinding from solid

Threads Per Inch

6 to 16

16 to 24

Carborundum

1003-A315 (Res.)
1503-

A315 (Res.)

For Grinding Pre-cut Threads

6 to 16

16 to 24

120-N-T (Vit)

150-N-T (Vit.)

100-S9TH (Res.)

150-T9TH (Res.)

3880-18BE (Vit)
$8120-J7BE (Vit)

120-10E20-2 (Res.)

150-10E20-2 (Res.)

38150-K8BE (Vit)

MacklinNorton

100-W9T-H (Res.)
150-W9T-H (Res.)

♦38120-K8BE (Vit)
♦38220-M10BE (Vit.)

♦100 10G20-2 (Res.)
♦150 10G20-2 (Res.)

100 10G20-2 (Res.)
150 10G20-2 (Res.)

ACME THREADS

TOOL AND ALLOY STEELS, HARDENED

For Grinding Pre-cut Threads

2 to 8

9 to 20

♦80-R-100 (Vit.)

80-R-100 (Vit.)

3880-J8BE (Vit.)

♦38120-J7BE (Vit.)

♦These wheels have performed especially well in their groups.

WHEELS FOR GRINDING NON-FERROUS METALS

Due to the large variation of the physical properties of these metals

struct a table of wheel recommendations.

CARBORUNDUM

Some of these metals are best ground with

Aloxite Resinoid while others require Car
borundum Vitrified or AA Aloxite Vitrified.
All such cases should be referred to the wheel

manufacturer.

Bronze, Brass and Aluminum are generally



ground with 37100-1, 37180-1 Crystalon Vit
rified or finer for fine pitches. The Norton

Representative should be consulted for rec

ommendations.

906

100 10G20-2 (Res.)
150 10G20-2 (Res.)

it is impossible to con

NORTON







GRINDING WHEEL SPEEDS - %" TO 6" DIAMETER WHEELS

WHEEL

18000

17000

16000

15000

14000

13000

12000

11000

10000

% % 1 1 Vs 4 13/8 1 !/2 1% 1 % 1% 2 2/8 2

2_% 2i/

2 IN INCHES

2%

3

3/4

3/

2

3%

4

4/4
4/2

4%

RPM

9000

8000

7000

6000

5000

4000

3000 4000 5000 6000 7000 8000 9000

WHEEL SURFACE SPEED IN FEET PER MINUTE-

10000

*

5
5/4

5/2
5%

6

11000 12000

B4323-A

GRINDING WHEEL SPEEDS -

2700

2600

2500

2400

2300

2200

2100

2000

12" TO 18" DIAMETER WHEELS

1900

1800

1700

1600

1500

1400

1300

1200

B4323-B

RPM

1100

1000

3000 4000 5000 6000 7000 8000

WHEEL SURFACE SPEED IN FEET PER MINUTE

9000 10000 11000

*-

12000

170

WORK SPEEDS

Vs V

a

V

s

TO lOO FEET PER MINUTE

<■

-------- WORK

V

i

V

s

V

a

V

s

1

ll/s 114 13/

s

V/

2 1% l3/

4 1% 2

2

V

DIAMETER

a

IN

INCHES

160

150

140

130

120

no

100

90

80

2Vi

23/

3

3j/

4

41/2

5

> f

4

2

RPM

70

60

50

40

30

20

10

0

0

10

WORK SURFACE SPEED IN FEET PER MINUTE

20

30

40

50

60

6

7

8
9

10

11
12

90

70

80

*

100

B4323-C

WORK SPEEDS

TO 300 FEET PER MINUTE

- WORK
DIAMETER

IN INCHES

7

8

9

10

11

12

B4323-D

RPM

■

!,

J

30 ISE

20

10

0

100

:

>

gg

Tj=j=f

i

m

3 ;

-

1

ISlI

III

44-14- IRXT

uj.l

USUI

lio

120 140

WORK SURFACE SPEED IN FEET PER MINUTE

1

till

TrrrrS±

S

11

IS:

130

mm

T

1

:

7T

m

:

I

tS

-I-;

iffl

R-R-

150 | 170

■

W\: fig H i

'

-I-

m

WF

m

-

m
m

I®

1 IS 1

ffi

fffi

-----

»

:

160 180

r

W

rri

;rl

f

ipR: RTF

I

±R

p;

—

■ ■

1

190

::

210

200 220 240

m

m

a

H

Rf

fR

m

9

■ ; -

|»

^tTRtR

230

->

ss

m

t

4

5

Se

3±S

mm

is®

250

270

260 280 300

•m

H

■

A

290

S

I

REPLACEMENT PARTS

EX-CELL-O PRECISION THREAD GRINDERS

STYLES 35 and 35-L

Only parts that may need replacement are
included in this list. The majority of machine
parts last as long as the machine itself. If it
should become necessary to replace a part that
is not included in this list the order can be filled
if the following information is forwarded:

ma-

chine serial number, description of the part

and, if necessary, a sketch.

Electrical equipment, V-belts and other

standard items can be purchased at the nearest

WWi

branch of the supplier. For commercial re

placement parts listed, equivalent products

of other makes may be used.

To avoid errors and unnecessary delays

when parts are ordered, the following infor

mation should be furnished:

1.

Part number and name of item.

2. Quantity

3. Machine serial number.





Part

Number

48-282
48-538
48-551
48-1805

crcax

t

48-551

Name of Part

Required

TAILSTOCK ASSEMBLY

Plunger ......................

Plunger Spring .........

Spring

..........................

Center (high speed steel) ... 1

TAILSTOCK ASSEMBLY

Number

Part

Number

48-1815

1
1
1

48-1816

48-2458
48-2467
48-2468

ravw {

Quill

Felt Seal
Lever

Pinion Shaft

Hinge Block

48-2458
48-2468

48-538
48-2467

-48-282
48-1805

Name of Part

...........

....

..........

Number

Required

1

1
1
1
1

1001

REPLACEMENT PARTS

Part

Number

B-785-A

Name of Part

EXTERNAL WHEEL SPIN

Number

Required

DLE ASSEMBLY (notshown)

WHEEL SLIDE ASSEMBLY (not shown)

48-546
48-577

Wheel Mounting Gasket ....

Motor Pulley (60 cycle)

....

Ball Bearings, Fafnir:
201 (K or W) A.B.E.C.-l

for handwheel shaft ...........

203 (K or W) A.B.E.C.-l

for handwheel shaft

...........

Ball Bearings, N.D.:
5207 A.B.E.C.-3 for worm
shaft

.......................................

0L10-DF A.B.E.C.-3 for

wheel feed screw nut

.........

Bearing, Torrington:

GB-1612-X for worm shaft.. 1

GB-3424-X for wheel feed

screw nut ........................

.

V-Belts for wheel drive,

Gates :

75-B

...................................

81-B...................................

-SB-260?

48-2608

48-447

48-2610

COOLANT MANIFOLD ASSEMBLY

48-8407

COOLANT MANIFOLD
ASSEMBLY

48-447
48-759
48-2608
48-2609
48-2610

Screw .............................

Spout .............................

Manifold

Manifold End ...............

.........................

Shutoff Valve .

.............

.

AUTOMATIC WHEEL FEED ASSEMBLY

(not shown)

48-3835

Thrust Bearing ..................

17528 Oil Seal, Perfect

.......

HYDRAULIC CONTROL ASSEMBLY

48-1557

Direction Valve ....................

48-1561-A Knob .......................................

Jr



1

2

1

1

1

1

y-

1

Part

Number

1

1

48-1578

1

49 F-5

49

F-8
49 F-9
49 F-ll
49 F-12
49

F-13
49 F-lS
49 F-16
49

F-18
49 F-24
49 F-25

1

2

49 F-47

Cl-304
1
1
1

48-1824

2

48-1907

1

48-1928

48-1929
1
1

48-1991

48-1992

ft ,

HYDRAULIC CONTROL ASSEMBLY

Name of Part

Required

BASE ASSEMBLY (not shown)

Hydraulic Pump Control

Line Tube

.........................

LUBRICATING PUMP ASSEMBLY

Cap Gasket
Strainer, Upper
Strainer, Lower
Gasket, Intake and Exhaust
Intake

Exhaust Spring ..............

Gage Glass .
Gasket
Gasket

Brass Bushing ......................

Washer.....

Spring .....................................

.............................

......................

.....................

Spring

..........................

............................

.....................................

.....................................

..............................

.

Copper Gasket ......................

15/16" Welch Plug

...............

5/16" Diameter Steel Ball ..

TABLE ASSEMBLY

Lead Pick-Up Pinion (not

shown) ...............................

Worm Shaft

Plunger .............................

........................

.

Spring ................................

Washer

Anchor Block

.........................

..................

.....

.

Number

1

1
1
1

2

1
1
1

2

1
1
1
1
1
1

2

2

1
1
1
5

1

1002

REPLACEMENT PARTS

/

49F-16

49F-5

49F-18

/

Ui

a

49F-25

\ \

\

\

Cl-304
49F-11
49F-13
49F-47
49F-1
49F-11

\

\
\
\

\
\

\

2

\

\

\ \ \ \

/

49F-15 49F-16

7602-DF

48-2480
48-1907

48-1992

48-1928
48-1929

49F-24 49F-8 49F-9

LUBRICATING PUMP ASSEMBLY

306

•5206
48-2481

48-2056
48-2053

48-1995

TABLE ASSEMBLY PARTS

1003

REPLACEMENT PARTS

Part

Number

48-1995
48-2047

48-2053
48-2056
48-2065
48-2066
48-2067
48-2068

48-2069
48-2480

48-2481
48-7548

Name of Part

TABLE ASSEMBLY (CONT’D)

Center .....................................

Hydraulic Tube Support (not

shown) .....................................

Nut
Nut .

....................................

Idler Sleeve ......................

Sleeve
Sleeve _

................................

...........................

.

Bushing, Compound Idler

Gear

...................................

Bushing, Single Idler Gear ..
Stud

Stud .........................................

Pump Body ............................

Ball Bearings, Fafnir:
5209 A.B.E.C.-5, for lead

screw drive pinion shaft

(not shown) .............................

209 (K orW) A.B.E.C.-5, for
lead screw
(not shown) .

drive

pinion shaft

............................

206 (K or W) A.B.E.C.-3 for
rear end of worm shaft

........

206 (K or W) A.B.E.C-5 for
inner end of horizontal lead
screw drive shaft, and for

upper end of vertical lead
screw drive shaft

...............

306 (K or W) A.B.E.C.-5 for
lower end of vertical lead

screw drive shaft .................

5206-A.B.E.C.-5 for outer
end of horizontal lead screw
drive

shaft .............................

7206 DF A.B.E.C-3 for front

end of worm shaft .................

V-Belt, for work spindle

drive:
Gates 2380

(not shown)

Oil Seal, Perfect:

41234 for work spindle (not

shown)
30024 for lead screw drive

(not shown)

.......................

18712 for headstock drive

shaft (not shown) ..............

Number

Required

1

1
5
1
1
1

2

1

5
3

1
1

1

1

.

.....

Part

Number

Name of Part

IDLER PULLEY ASSEMBLY

Number

Required

(for work spindle drive)

(not shown)

Ball Bearing, Fafnir:
204 (K or W) A.B.E.C.-l

......

2

WORK SPINDLE ASSEMBLY

(not shown)

48-1915

48-1916

48-1922
XLO 120

Bronze Worm Gear
Spacer

Lock Nut ........................

.............................

Ball Bearing .

48-2983

.......

................

1
.
.
.

1

1

2

1

48-2984

2

48-2428

1

48-7
48-2982

1
1

48-2983

48-2984

ROLLER CAGE ASSEMBLIES

WORK DRIVER ASSEMBLY

WORK DRIVER ASSEMBLY

Screw

....................

Work Driver Plate

Driver ...................

Lock Nut ...............

1

L

1

1

(not shown)

48-6402

1

48 - 64 0 8
48-6403
48-6409

2

1

48-3540
48-3907

1

V-Roller Cage (Wheel Slide)

Flat Roller Cage (Wheel Slide) 1

V-Roller Cage (Table)

........

Flat Roller Cage (Table) ...

VARIABLE SPEED HYDRAULIC
MOTOR

ASSEMBLY (not shown)

Gasket

.....................................

Motor Fitting (with 1

” pipe

thread) ...................................

1

2

2

1

1

1004

REPLACEMENT PARTS

Part

Number

48-3908

Name of Part

Motor Fitting (with 3/4" pipe

Number

Required

thread) ....................................

Ball Bearing, N.D.
55505 A.B.E.C.-l

:

..................

60237 Victoprene Oil Seal .. 1

AUTOMATIC FEED, STOP AND DRESS
CONTROL ASSEMBLY (not shown)

48-3963

Bronze Bushing For Dresser
Start and Feed Control Shaft 1

48-3976

Torsion Spring For Dresser
Start and Feed Control Shaft 1

DRESSER SLIDE ASSEMBLY

(not shown)

Bearing, Torrington:
GB-T412-X For Dresser

Feed Shaft

............................

GB-1616-X For Dresser

Feed Screw

........................

Ball Bearing, N.D.:
20304

-DF A.B.E.C.-3 For

Dresser Feed Screw

.........

5205 A.B.E.C.-3 For

Dresser Feed Shaft

60245 Victoprene Oil Seal.,

..........

1

WORK TABLE CONTROL DOG ASSEMBLIES

(not shown)

48-1375
48-1596

48-1377
A6-1

RIGHT HAND STOP DOG

ASSEMBLY ......................

Base

....................................

Lever....

.............................

Nut

.

Socket Head Screw 5/16 - 18

x 2

C-1110 - Q Bantam Roller

48-1376

LEFT HAND STOP DOG

ASSEMBLY......................

Base

48-1596

48-1377

A6-1

...................................

Lever .

Nut

...............................

.....................................

Socket Head Screw 5/16 - 18

x 2

48-1579
48-1584
48-1384

C-1110 - Q Bantam Roller

RIGHT HAND SAFETY DOG
LEFT HAND SAFETY DOG

RIGHT HAND REVERSE DOG 1

Part

Number

A6-1

1

1

48-1385

Name of Part

Nut

Socket Head Screw 5/16 - 18

x 7/8

.........................................

LEFT HAND REVERSE DOG

ASSEMBLY ............................

48-1588
A6-1

Left Hand Reverse Dog .......

Nut ...........................................

Socket Head Screw 5/16 - 18

48-1580
48-1581
48-1582

x 7/8 ........................................

FEED DOG ASSEMBLY ......

Base

.........................................

Lever .......................................

Number

Required

1

1

1
1
1

1

1
1

1
Socket Head Screw 5/16 - 18

x 1-1/2 ..................................

C-1110-Q Bantam Roller
1
1

48-1585

48-1586

48-1582

A6-1

1
1

48-1590
48-1586

48-1592

1

A6-1

1
1
1

48-8867-3

1
1

RAPID TRAVERSE DOG

ASSEMBLY .....................

Base

..................................

Lever ..............................

Nut
Socket Head Screw 5/16 - 18

x 1
C-1110-Q Bantam Roller

RAPID RETURN DOG

ASSEMBLY .................

Base

..............................

Lever ..........................

Nut

DRESSER DRIVE ASSEMBLY

(not shown)

Flexible Drive Shaft Assembly

for Three Way 60° and 29

FormDresser andThreeWay
Plate-Type 10° to 90° Form

.
.
.

Dresser ....................................

1

48-8867-4

1
1
1

Flexible Drive Shaft Assem

bly for Three Way Cradle-
Type 10° to 90° Form

Dresser and Universal Cam-

Type Dresser ........................

1

48-8855-3

1
1

48-8855-4

Core for Flexible Drive Shaft

Assembly 48-8867-3 ..........

Core for Flexible Drive Shaft

Assembly 48-8867-4 ..........

1

48-8946
1200

Brake Belt

..............................

Gates V-Belt ........................

1
1

1
1
1
1

1
1

1
1
1
1

1



1
1

1
1
1

1005

REPLACEMENT PARTS

Part

Number

Name of Part

INTERNAL GRINDING ATTACHMENT

(not shown)

B-630

12-S-626

12-S-627

Internal Grinding Spindle

Assembly ...............

-...............

Quill for 2-1/2" to 4" di

ameter wheels

........................

Quill for 1" to 2-1/2" di
ameter wheels

........................

Ball Bearing, N.D.:
3204 A.B.E.C.-l For Idler
Pulley

.....................................

3205 A.B.E.C.-l For Counter
shaft Pulley

.............................

2470 Gates V-Belt, Motor to

Countershaft ............................

Flat Belt, 1-1/2" wide x 63"

long, Gates Speedflex Cross

cord R-5-210-B ......................

Number

Required







-

1

1
1

2

2

1

FLEXIBLE HOSE FROM TABLE TO

1

HYDRAULIC MOTOR

Part

Number

48-534-3
48-1640
48-7650-1

48-7650-1
48-7650-1

48-7650-1

48-7650-2
48-7650-3
48-7650-6
48-7650-7
48-7650-8
48-7651-1
48-7651-2
48-7651-4
48-7651-5
48-7651-6

FLEXIBLE HOSE

Where used

Coolant Tank to Wheel Slide (not shown)

Hydraulic Sump to Pump Intake (not shown)

...............................

......................

Under Wheel Slide, Base to Wheel Feed Nut (not shown) .
From Coolant Pipe to Dresser (not shown)

..............

.. , . ,

Under Wheel Slide, Base to Dresser Box (not shown) . . .

Table to Backlash Compensator
Table to Backlash Compensator

.............................................

........................................

Under Wheel Slide, Base to Dresser Box (not shown) . , .
Left End of Base to Table . , . .

Center of Base to Table

...........................................................

Table to Backlash Compensator
Hydraulic Filter to Base

...........................................................

Left End of Base to Table
Center of Base to Table*

...........................................................

Table to Hydraulic Motor

Table to Hydraulic Motor
Base to Sine Bar Follower (under table) Bijur B-3135
or equivalent (not shown)

...............................................

.............................................

..........................................

.. . . . .

.....................................................

.......................................................

.......................................................

Overall

Length Required

45"

15-1/4"

24"

24" -

24"
24"

22-5/8"

..

27-1/2"

52"

36"-

18-1/2"

14"
52"

38"

39-1/2"

..

30-1/2"

15"

Number

1
1
1
1

2

1
1
1
1

2

1
1

2

1
1
1

1

1006

REPLACEMENT PARTS

FLEXIBLE HOSE FROM BASE TO TABLE

Part

Number

Name of Part

Number

Required

THREE WAY 60° and 29° FORM DRESSER

Shaft

48-3011
48-3012

48-3017
48-3020
48-3023
48-3026
48-3027
48-3028
48-3031
48-3032

48-3033

48-3034
48-3035
48-3054
48-3056
48-3077

Washer Seal

......

Bushing .
Cam Stud
Gib
Felt Washer ...
Cam Block
Plunger

......

......

.

.

Plunger Spring

Shaft ...............

Shaft Bearing .

....

Felt Seal .........

.
Stud
Adjusting Collar
Switch Trip Arm

Bushing ..............

r

]

1
1
1
1
1
1
1
1

2
2

2

Part

Number
48-3078

48-3079

4

2

2

1

48-3082
48-3083
48-3084

1

FLEXIBLE HOSE FROM TABLE TO

BACKLASH COMPENSATOR

Name of Part

Lead Screw Shaft (not shown) 1
Lead Screw Shaft Bushing,

Long (not shown) ............

Worm Shaft .....................

Drive Collar ..................

Worm Shaft Bushing (not

shown) .

48-7650-8

48-7650-2

48-7650-1

.............................

Number

R

equired

.
.

£

1
1
1

1

1007

BZR
48-3161
48-3136
48-3054

48-3026
48-3136-1

48-3035
48-3056
48-3027
48-3034
48-3031

^ <9

REPLACEMENT PARTS

A-627
48-3089

48-3077
48-3083

48-3166

8-3082

48-3137
48-3097
48-3023
48-3020
48-3028
48-3011
48-3246
48-3012

48-3017
48-3033
7/16 BALL
48-3032

THREE WAY 60° AND 29° FORM DRESSER

Part

Number

Name of Part

Number

Required

THREE WAY 60° and 29° FORM DRESSER

(CONT'D)

48-3089
48-3097
48-3136
48-3137
48-3136-1
48-3161
48-3166
48-3167
48-3246

A-627

Bronze Washer

......

.

Spring .............................

Ball Joint Assembly ....

Spring Plate

..................

Ball Joint Assembly ....

Switch Cam
Worm

.....................

..........................

.
Worm Gear (not shown)
Bronze Lead Screw Nut
Oilite Bushing...

.........

• i

.

Part

Number

1

THREE WAY, PLATE-TYPE 10° to 90° FORM

1

DRESSER AND THREE WAY, CRADLE-TYPE

2

10 to 90 FORM DRESSER

1

2

1
1
1
1
1

48-3023

48-3031
48-3032

48-3033

48-3034
48-3077

Name of Part,

10012 Perfect Oil Seal,
Switch
BZ-R Micro-Switch

Shaft (not shown)

.......

Felt Washer..
Shaft

..............

Shaft Bearing

Washer .........

Felt Seal ......

Bushing

.........

Number

Required

1

1

1

2
3
2
6

1

1008

REPLACEMENT PARTS

Part

Number

48-3078
48-3079

48-3082
48-3083

48-3084

48-3089
48-3097
48-3136
48-3136-1
48-3166
48-3167
48-3246
48-3212
48-3247
48-3251
48-3252

Name of Part

Required

Lead Screw Shaft .................

Lead Screw Shaft Bushing

(Long) ......................................

Number

Worm Shaft

............................

Drive Collar .........................

Worm Shaft Bushing ...........

Bronze Washer
Spring

......................................

.......................

Ball Joint Assembly, front -
Ball Joint Assembly, rear...

Worm ......................................

Worm Gear ............................

Bronze Lead Screw Nut

......

Diamond (not shown) ...........

Gib
Cam Stud .,
Cam Block

Part

Number

1

48-3254
48-3256

1
1
1

48-3262
48-4105-1
A-

62 7
1
1

3
2

2
1
1

1
1
1
1

1

UNIVERSAL

48-4011

48-4012
48-4014

48-4015-A Bushing, R.H
48-4016
48-4017
48-4018
48-4019

Name of Part

Switch Trip Bracket ...........

Center Arm Shaft
Adjusting Pin
Diamond

(not shown) ...........

Oilite Bushing

.................

......................

........................

16-D-1200 2 Snap Lock Switch,
National Acme Co

CAM-TYPE DRESSER

..................

End Plate .................

Cam Carrier ..........

Bronze Worm Wheel

Bushing, L.H. .
Bushing Spacer
Key

....................

Bearing Nut ...

Number

Required

..

1
1

2
2

1

1

1

1

1
1

1
1
1

2

16-D-l 200-2

48-3078
48-3082
48-3247

THREE WAY PLATE TYPE 10° TO 90° FORM 0RESSER AND THREE WAY CRADLE TYPE

48-3097

48-3246
48-3136

48-3136-1

10° TO 90° FORM DRESSER

A627
48-3251
48-3089

48-3033

48-3262

48-3166
48-3167

48-3084
48-3034

48-3079

48-3023
48-3031
48-3256

48-3032
48-3083
48-3077

1009

48-4099
48-4127 —
48-41

20-A
48-4121%
48-4069
48-4067.
48-4068

48-4071*

48-4070
48-4072
48-4119'
48-4030
48-4040
48-4033

48-4031
48-4032

REPLACEMENT PARTS

48-4011

48-4026

-//Y)

i .

—

ft f

i

rv

OS

:

>v

.

a

/

\0

a

.1

tS

ji

48-4036'
48-4035'
48-4029-
48-4038-
48-4037
48-4044
48-4043

^3

I i#9]]|

HI

&

/ /

■y

■T.A

SEW#

r

48-8803

i

✓

/'/.

■

r f //

Z

'■W.Sfcj

/

>

</

V

*/

48-4034-A

48-881

»

*V

/9

48-4046

9-A

R-RS-55

I >

S=>

a

> O

'■

4°>.

.

O.

:

Q1342

■48-8807
’

48-8805

‘

48-8804

S,

B-812

■48-4045

■48-8861

■48-4059
.48-4125

48-8817
48-8835 ^

il

-A

'■

48-401
*48-4111
‘

48-4017

'MM9507

■48-4039
’

48-4016

*48-4075

48-8806
HQVH

M-471

48-4110
B-47

■48-8808

5-A

■48-4060
48-4061

48-4202

■48-4064

•48-4014

■48-4201

■48-4018
48-4084

■48-4062

•48-4063

—r'1

o

>A^

j;

■48-4021
’

48-4023

•48-4024

•48-4020

■48-4019

■48-4025
48-4022

‘

48-4012

’

48-4023

Part

Number

Name of Part

UNIVERSAL CAM-TYPE DRESSER

(CONT’D)
48-4020
48-4021
48-4022
48-4023
48-4024
48-4025
48-4026
48-4029

48-4030

48-4031

48-4032

48-4033
48-4034-A Cover Screw
48-4035
48-4036

Washer ...................................

Cam Nut .................................

Retainer for Felt Wiper ....

Felt

Wiper .............................

Bearing Equalizing Ring ....

Bearing Nut ...........................

End Plate

................................

Bushing, Diamond Carrier

Guide ......................................

Wear Plate .

Spring Plunger

Spring ..........

Diamond Carrier, R.H

...........................

Diamond Carrier, L.H

1010

UNIVERSAL CAM-TYPE DRESSER

Number

Required

2
2
2
2
2
2

1

2

1

2

.........

.........

2

2

2

1
1

Part

Number

48-4037

48-4038

48-4039

48-4040
48-4043
48-4044
48-4045
48-4046
48-4059
48-4060
48-4061
48-4062
48-4063

48-4064
48-4067
48-4068
48-4069

Name of Part

Spring, Diamond Adj. Screw

Diamond Adjusting Screw ...

Cam Follower Adj. Screw ..
Cam

Follower ......................

Drive Worm ......................

Bronze Washer ....................

Bronze Bushing ....................

Bronze Bushing ...................

Sector Gear ...........................

Pinion Gear ....................

Horizontal Angle Adj. Screw

Guide, Rear .
Guide, Front

..........................

.........................

Swivel Bracket Lock Screw
Guide Block

..........................

Wear Plate, Front ..............

Wear Plate, Rear ...............

Number

Required

.

2
2
2

2

1

2

1
1
1
1

2

1
1

2

1
1
1

REPLACEMENT PARTS

Part

Number

48-4070
48-4071
48-4072
48-4075
48-4099
48-4110
48-4111
48-4119
48-4120-A
48-4123
48-4127
48-4201
48-4202
48-8803
48-8804
48-8805
48-8806
48-8807
48-8808
48-8817
48-8835

Name of Part

Screw

...............................

Number

Required

Spring ............................

Shoulder Screw ...........

Cam Follower Bushing

Coolant Manifold .........

Guide

...............................

Key
Knob

Stop Wedge ............................

Lead Screw

.......................

.

Wedge Bushing Plunger ....

Switch Trip Arm, R.H

Switch Trip Arm, L.H

.........

.........

Shaft .......................................

Washer ...................................

Washer ...................................

Worm Shaft ...........................

Washer ...................................

Needle Bearing Retainer ...
Plunger

..................................

Sleeve ...................................

Ball Bearing, Fafnir:

MM 9507 ................................

Bearings, Torrington:

Part

Number

2
2

1

2

1
1
1

43-1145

1
1
1

48-4105-1
4
1

48-4128

1
1

1
1
1

2

1

2
2

48-4270
48-4271
48-4272
48-4305
48-4317
48-4335
48-4336
48-4338
48-4339

2

X-844

Name of Part

B-47 for drive end on
48-8806 shaft

........................

B-812 for 48-8803 shaft ....

M-471 for 48-8806 shaft

Boston Worm, HQVH .........

Boston Worm Wheel, Q1342

Micro-Switch, R-RS-55 ....

INTERNAL PANTOGRAPH-TYPE

DRESSER

Diamond, for Straight Line

Thread Forms (not shown)

Diamond, for Radius Thread

Forms (not shown) ..............

Shoulder Screw .

...................

Shoulder Screw .....................

Shoulder Screw .....................

Anchor Pin ...........................

V-Rail ....................................

V-Slide ...................................

Hinge Pin ...............................

Bushing ...................................

Bushing .
Bushing .

.................................

..................................

.1875 dia. Steel Balls ..........

Number

Required

1
1

....

1
1
1

2

60

2

2
2

1
1
1
4

2

1
1
5

2

48-4317

48-4335
48-4305
48-4272
48-4338
48-4339

48-4270“* 48-4271

INTERNAL PANTOGRAPH TYPE DRESSER

X-844

48-4336

STEEL BALLS

1011