Jet BD-920W Operating Instructions Manual

3

GB - ENGLISH

Operating Instructions

Dear Customer,
Many thanks for the confidence you have shown in us with the purchase of your new JET-machine. This manual has been

prepared for the owner and operators of a JET BD-920W metal lathe to promote safety during installation, operation and
maintenance procedures. Please read and understand the information contained in these operating instructions and the
accompanying documents. To obtain maximum life and efficiency from your machine, and to use the machine safely, read this
manual thoroughly and follow instructions carefully.

…Table of Contents

1. Declaration of conformity

2. Warranty

3. Safety

Authorized use
General safety notes
Remaining hazards

4. Machine specifications
Technical data
Noise emission
Contents of delivery

5. Transport and start up
Transport and installation
Assembly
Mains connection
Starting operation

6. Machine operation

Controls
Chucking
Tool setup
Spindle speed selection
Manual turning
Turning with auto feed
Thread cutting
Drilling operation

7. Setup and adjustments

Change gear setup
Turning between centres
Taper turning with tailstock
Taper turning with top slide
Three jaw universal chuck
Four jaw independent chuck
Live centre
Steady and follow rest

8. Maintenance and inspection

Lubrication schedule
Bearing adjustment
Cross and top slide adjustment
Cross slide spindle adjustment
Top slide spindle adjustment
Spindle end float adj.
Halve nut adjustment
Shear pin replacement

9. Trouble shooting

10. Environmental protection

11. Available accessories

1. Declaration of conformity

On our own responsibility we hereby
declare that this product complies
with the regulations* listed on page

2. Designed in consideration with
the standards**.

2. Warranty

The Seller guarantees that the
supplied product is free from
material defects and manufacturing
faults. This warranty does not cover
any defects which are caused, either
directly or indirectly, by incorrect
use, carelessness, accidental
damage, repair, inadequate
maintenance or cleaning and normal
wear and tear.

Guarantee and/or warranty claims
must be made within twelve months
from the date of purchase (date of
invoice). Any further claims shall be
excluded.

This warranty includes all guarantee
obligations of the Seller and
replaces all previous declarations
and agreements concerning
warranties.

The warranty period is valid for eight
hours of daily use. If this is
exceeded, the warranty period shall
be reduced in proportion to the
excess use, but to no less than three
months.

Returning rejected goods requires
the prior express consent of the
Seller and is at the Buyer’s risk and
expense.

Further warranty details can be
found in the General Terms and
Conditions (GTC). The GTC can be
viewed at www.jettools.com or can
be sent by post upon request.

The Seller reserves the right to
make changes to the product and
accessories at any time.

3. Safety

3.1 Authorized use

This metal lathe is designed for
turning and drilling machinable
metal and plastic materials only.
Machining of other materials is not
permitted and may be carried out in
specific cases only after consulting
with the manufacturer.

Never cut magnesium­high danger to fire!

The workpiece must allow to safely
be loaded and clamped.

The proper use also includes
compliance with the operating and
maintenance instructions given in
this manual.

The machine must be operated only
by persons familiar with its operation
and maintenance and who are
familiar with its hazards.

The required minimum age must be
observed.

The machine must only be used in a
technically perfect condition.

When working on the machine, all
safety mechanisms and covers must
be mounted.

In addition to the safety
requirements contained in these
operating instructions and your
country’s applicable regulations, you
should observe the generally
recognized technical rules
concerning the operation of
metalworking machines.

Any other use exceeds
authorization.
In the event of unauthorized use of
the machine, the manufacturer
renounces all liability and the
responsibility is transferred
exclusively to the operator.

4

3.2 General safety notes

Metalworking machines can be
dangerous if not used properly.
Therefore the appropriate general
technical rules as well as the
following notes must be observed.

Read and understand the entire
instruction manual before attempting
assembly or operation.

Keep this operating instruction close
by the machine, protected from dirt
and humidity, and pass it over to the
new owner if you part with the tool.

No changes to the machine may be
made.

Daily inspect the function and
existence of the safety appliances
before you start the machine.
Do not attempt operation in this
case, protect the machine by
unplugging the power cord.

Remove all loose clothing and
confine long hair.

Before operating the machine,
remove tie, rings, watches, other
jewellery, and roll up sleeves above
the elbows.

Wear safety shoes; never wear
leisure shoes or sandals.

Always wear the approved working
outfit.

Do not wear gloves.
Wear goggles when working
Install the machine so that there is

sufficient space for safe operation
and work piece handling.

Keep work area well lighted.
The machine is designed to operate

in closed rooms and must be placed
stable on firm and levelled ground.

Make sure that the power cord does
not impede work and cause people
to trip.
Keep the floor around the machine
clean and free of scrap material, oil
and grease.

Stay alert!
Give your work undivided attention.
Use common sense. Do not operate
the machine when you are tired.

Keep an ergonomic body position.
Maintain a balanced stance at all
times.

Do not operate the machine under
the influence of drugs, alcohol or
any medication. Be aware that
medication can change your
behaviour.

Never reach into the machine while
it is operating or running down.

Never leave a running machine
unattended. Before you leave the
workplace switch off the machine.

Keep children and visitors a safe
distance from the work area.

Do not operate the electric tool near
inflammable liquids or gases.
Observe the fire fighting and fire
alert options, for example the fire
extinguisher operation and place.

Do not use the machine in a dump
environment and do not expose it to
rain.

Work only with well sharpened tools.
Always close the chuck guard and

pulley cover before you start the
machine.

Remove the chuck key and
wrenches before machine operation.

Specifications regarding the
maximum or minimum size of the
work piece must be observed.

Do not remove chips and work piece
parts until the machine is at a
standstill.

Do not stand on the machine.
Connection and repair work on the

electrical installation may be carried
out by a qualified electrician only.

Have a damaged or worn power
cord replaced immediately.

Never place your fingers in a
position where they could contact
any rotating parts or chips.

Check the save clamping of the
work piece before starting the
machine.

Don’t exceed the clamping range of
the chuck.

Work pieces longer than 3 times the
chucking diameter need to be
supported by the tailstock or a
steady rest.

Avoid small chucking diameters at
big turning diameters.

Avoid short chucking lengths.
Avoid small chucking contact.

Never exceed the max speed
limitation of the work holding device.

Choose a small spindle speed when
working unbalanced work pieces
and for threading and tapping
operations.

Any work piece stock extending the
rear end of the headstock must be
covered on its entire length. High
danger of injury!

Long work pieces may need a
steady rest support. A long and thin
work piece can suddenly bend at
high speed rotation.

Never move the tailstock or tailstock
quill while the machine is running.

Remove cutting chips with the aid of
an appropriate chip hook when the
machine is at a standstill only.

Never stop the rotating chuck or
work piece with your hands.

Measurements and adjustments
may be carried out when the
machine is at a standstill only.

Setup, maintenance and repair work
may only be carried out after the
machine is protected against
accidental starting by pulling the
mains plug.

3.3 Remaining hazards

When using the machine according
to regulations some remaining
hazards may still exist.

The rotating work piece and chuck
can cause injury.

Thrown and hot work pieces and
cutting chips can lead to injury.

Chips and noise can be health
hazards. Be sure to wear personal
protection gear such as safety
goggles and ear protection.

The use of incorrect mains supply or
a damaged power cord can lead to
injuries caused by electricity.

4. Machine specifications

4.1 Technical data

Swing over bed 225mm
Swing over cross slide 135mm
Centre distance 500mm

Spindle taper MT-3
Spindle nose short taper D1-38
Hole through spindle ∅20 mm
Spindle speeds…6 110-1700 rpm

5

Tailstock ram travel 40mm
Tailstock taper MT-2

Cross slide travel 125mm
Top slide travel 45mm
Tool size max 12 x 12 mm
Lead screw pitch 1,5mm
Gear box transmissions 0,5 / 1 / 2
Longitudinal feeds...20 0,02–0,5mm/r
Metric threads...13 0,4–3,5mm/r
Inch threads…28 8 – 60 TPI

Dimension LxWxH 940x510x500mm
with optional stand H 1140mm
Net weight 110 kg

Mains 230V ~1/N/PE 50Hz
Output power 0,55 kW (0,75 HP) S1
Reference current 4 A
Extension cord (H07RN-F): 3x1,5²
Installation fuse protection 10A

4.2 Noise emission

Acoustic pressure level
(according to EN ISO 11202):
Idling at maximum speed
LpA 71,2 dB (A)

The specified values are emission
levels and are not necessarily to be
seen as safe operating levels.
As workplace conditions vary, this
information is intended to allow the
user to make a better estimation of
the hazards and risks involved only.

4.3 Content of delivery

Four way tool post
Single tool holder
Steady rest
Follow rest
Set of change gears
MT-2 fixed centre
MT-3 fixed centre
Threading dial
Faceplate
180mm 4-jaw independent chuck
100mm 3-jaw universal chuck
Set of 3 OD chuck jaws
Assembly kit
Operating manual
Spare parts list.

5. Transport and start up

5.1 Transport and installation

The machine is designed to operate
in closed rooms and must be bolted
on a firm and levelled table surface
or on the original cabinet stand
(optional accessory).

5.2 Assembly

If you notice transport damage while
unpacking, notify your supplier
immediately. Do not operate the
machine!

Dispose of the packing in an
environmentally friendly manner.

Clean all rust protected surfaces
with petroleum, diesel oil or a mild
solvent.

Caution: The machine is heavy!
Use great care and adequate
resources when lifting.

To avoid twisting the bed, make sure
the setup surface is absolutely flat
and level.

Regarding change gear setup:

For packaging reason the change
gears #60 and #120 have been
installed in reversed order.

Install them as shown here.

5.3 Mains connection

Mains connection and any extension
cords used must comply with
applicable regulations.
The mains voltage must comply with
the information on the machine
licence plate.

The mains connection must have a
10 A surge-proof fuse.

Only use power cords marked
H07RN-F

Connections and repairs to the
electrical equipment may only be
carried out by qualified electricians.

5.4 Starting operation

You can start the machine with the
green on button. The red button on
the main switch stops the machine.

The spindle direction switch can be
set to forward or reverse operation.

Caution:
The spindle direction may not be
changed during machine
operation.

6. Machine operation
Warning:

Setup, maintenance and repair work
may only be carried out after the
machine is protected against
accidental starting by pulling the
mains plug.

Measurements and adjustments
may be carried out when the
machine is at a standstill only.

Check the save clamping of the
work piece before starting the
machine.

Never stop the rotating chuck or
work piece with your hands.

Never place your fingers in a
position where they could contact
any rotating parts or chips.

Remove cutting chips with the aid of
an appropriate chip hook when the
machine is at a standstill only.

Always close the chuck guard and
pulley cover before you start the
machine.

Choose a small spindle speed when
working unbalanced work pieces
and for threading and tapping
operations.

Never cut magnesium­high danger to fire!

6.1 Controls

Fig 1

1….Motor On/Off Switch
2….Motor Forward/Reverse Switch
3….Longitudinal Travel Hand Wheel
4….Half-Nut Lever
5….Cross Slide Hand Wheel
6….Top Slide Hand Wheel
7….Longitudinal Lock Screw
8….Tool Post
9….Tailstock Spindle Hand Wheel

6

10…Tailstock Spindle Clamping
Lever

11…Tailstock Locking Screw
12…Tailstock Off-Set Adjustment
13…Automatic Feed Lever
14…Change Gear Box Lever
15…Reversing Gear Lever
16…V-Belt Tension Lever

6.2 Chucking

Never exceed the max speed
limitation of the work holding device.

Jaw teeth and scroll must always be
fully engaged. Otherwise chuck jaws
may break and fly off in rotation (Fig

2).

Fig 2

Avoid long workpiece extensions.
Parts may bend (Fig 3) or fly off (Fig

4).
Use tailstock or rests to support.

Fig 3

Fig 4

Avoid short clamping contact (A, Fig

5) or clamping on a minor part
diameter (B).

Fig 5

Face locate the workpiece for added
support.

6.3 Tool setup

The cutting angle is correct when the
cutting edge is in line with the centre
axis of the work piece. Use the point
of the tailstock centre as a gauge
and shims under the tool to obtain
the correct centre height (Fig 6).

Fig 6

Use a minimum of two clamping
screws when installing the cutting
tool to the four way tool post.

Avoid big tool extensions.

6.4 Spindle speeds selection

The correct spindle speed depends
on the type of machining, the cutting
diameter, the material to be
machined and the cutting tool.

These are recommended max.
speeds for a 10mm cutting diameter
with HSS (high speed steel) tools:

Aluminium, brass 1500 RPM
Cast iron 1000 RPM
Mild steel 800 RPM
High carbon steel 600 RPM
Stainless steel 300 RPM
If carbide tools (HM) are used about

5 times higher speeds can be
chosen.

Generally speaking, the larger in
relation the cutting diameter, the
smaller the possible RPM.

For example:

Turning mild steel at a diameter of
20mm allows a speed of

400 RPM max. with HSS tool
2000 RPM max. with carbide tool

To change the spindle speed:

Unplug the machine from the power
source.

Loosen the locking screw on the
pulley cover, then open the cover.

Loosen the belt tension by lifting the
lever (A, Fig 7).

Fig 7

Change the belt location according
to the speed chart and the speed
you desire.

Tension the belt.
Close and lock the pulley cover.

6.5 Manual turning

Apron travel, cross travel and top
slide travel can be operated for
longitudinal and cross feeding (Fig

8).

Fig 8

7

6.6 Turning with auto feed

Three automatic longitudinal feeds
are readily available by selection on
the gearbox handle. Further feed
rates are possible by different
change gear setups.
By moving lever (A, Fig 9) upward,
the automatic feed is engaged.

Fig 9

The correct feed depends on the
material to be cut, the cutting
operation, the type of tool, the
rigidity of the work piece
chucking, the depth of cut and the
desired surface quality.

For example:

OD-turning mild steel of 20mm
diameter with an HSS tool at 350
RPM and with rigid chucking.
Change gear setup as shown (Fig

10).

Fig 10

Stock removal and roughing cut :

Depth of cut 1,5mm
Feed per revolution 0,15mm
(change gear box position III)

Finishing cut:

Depth of cut 0,5mm
Feed per revolution 0.07mm
(change gear box position II)

Micro finishing and calibration
cut:

Depth of cut 0,2mm
Feed per revolution 0.04mm
(change gear box position I)

When roughing big diameters
reduce the depth of cut!

6.7 Thread cutting

Threading is performed in multiple
passes with a threading tool.
Each depth of cut should be about
0,2mm and become less for the
finishing passes.

A) To cut inch and metric threads

Set the machine up for the desired
threading pitch and first depth of cut.

Engage the halve nut (A, Fig 11).
The halve nut must be engaged
during the entire threading process.

- Start the machine at the lowest
spindle speed.

- When the tool reaches the end of
cut, stop the motor and at the same
time back the tool out of the part so
that it clears the thread (Attention
inertia: Stop the motor in time)

- Reverse the motor direction to
allow the cutting tool to travel back
to the starting point.

Repeat these steps until you have
obtained the desired results.

Caution:
The spindle direction may not be
changed during machine
operation!

Fig 11

B) To cut metric threads with
pitch 0,4/ 0,5/0,75/0,8/1 /1,5 /2 /3
mm:

On these pitches the threading dial
(B, Fig 11) can be used.
The halve nut can be opened at the
end of cut, rather than the motor
being stopped and reversed.
The halve nut may only be engaged
at any graduation match (every
12mm on the lead screw).

6.8 Drilling operation

Use a drill chuck with MT 2 arbor
(option) to hold centring drills and
twisted drills in the tailstock.

Fig 12

For recommended speeds refer to
section 6.4

To eject the drill chuck, fully retract
the tailstock quill.

7. Setup and adjustments
General note:

Setup and adjustment work may
only be carried out after the
machine is protected against
accidental starting by pulling the
mains plug.

7.1 Change gear setup

Unplug the machine from the power
source.

Loosen the locking screw on the
pulley cover, then open the cover.

-Loosen screw (1, Fig 13)

-Unscrew bolt (2), remove washer
(3) and gear (6)

-Loosen bolt (7) to allow movement.

-Loosen nut (5), remove washer (4)
and gear (8)

Fig 13

Reassemble with desired gear setup

8

Adjust gear to mesh with upper and
lower gear.
Placing ordinary paper in between
gears helps to adjust for correct gear
spacing (… remove the paper
afterwards!).

Close and lock the pulley cover.

7.2 Turning between centres

Mount the work piece fitted with the
drive dog between centres.
The driver is driven by the face plate
(Fig 14).

Fig 14

Lubricate the tailstock centre with
grease to prevent tip from
overheating.

7.3 Taper turning with tailstock

Turning up to a side angle of 5° can
be achieved by off-setting the
tailstock.

To offset the tailstock, loosen the
locking screw (1, Fig 15), loosen the
front adjusting screw (2) and take up
the same amount on the rear
adjusting screw.
Tighten the adjusting screws and the
locking nut to hold the tailstock in
position.

The work piece must be held
between centres and driven by the
face plate and drive dog.

Fig 15

After taper turning, the tailstock
must be returned to its original
position.
Turn a test piece and adjust until the
machine turns a perfect cylinder.

7.4 Taper turning with top slide

By angling the top slide, tapers may
be turned.
Loosen two nuts (1, Fig 16) and
rotate the top slide according to the
graduated scale.

Fig 16

The top slide may be located in two
positions on the cross slide.

7.5 Three jaw universal chuck

With this universal chuck,
cylindrical, triangular and hexagonal
stock may be clamped (Fig 17).

Fig 17

To hold big diameter stock, a set of
3 OD chuck jaws is supplied.

The jaws always need to be inserted
to the chuck in the correct order.

Use Molykote Paste G (or adequate
grease) to lubricate the jaws.

7.6 Four jaw independent chuck

This chuck has four independently
adjustable chuck jaws (Fig 18).

These permit the holding of square
and asymmetrical pieces and enable
the accurate concentric set-up of
cylindrical pieces.

Fig 18

7.7 Live centre (optional)

The live centre is mounted in ball
bearings.
Its use is highly recommended for
speeds above 500 RPM.

Fig 19

To eject the live centre, fully retract
the tailstock quill.

7.8 Steady and follow rest
The steady rest

serves as a support for longer shafts
and ensures a safe and chatter free
operation.
The steady rest is mounted on the
bed way with a locking plate.

Tighten knurled screws (3, Fig 20)
so that fingers (2) are snug but not
tight against work piece. Tighten
nuts (1).

Lubricate the fingers to prevent
premature wear.

9

Fig 20

The follow rest

is mounted on the saddle and
follows the movement of the tool. It
prevents flexing of long and thin
work pieces under pressure from the
tool (Fig 21).

Fig 21

Set the fingers snug but not overly
tight. Lubricate the fingers to prevent
premature wear.

8. Maintenance and inspection
General notes:

Maintenance, cleaning and repair
work may only be carried out after
the machine is protected against
accidental starting by pulling the
mains plug.

Clean the machine regularly.
Defective safety devices must be

replaced immediately.
Repair and maintenance work on the

electrical system may only be
carried out by a qualified electrician.

8.1 Lubrication schedule

Refer to Fig 22 and Fig 23.

Weekly apply oil to:

1…oil ball on gear hub
3…teeth of reversing gear lightly
4…bed ways lightly
6…lead screw on entire length
7…oil ball on lead screw bracket
8…screw and guides of top slide
9…oil ball on tailstock body

10..oil ball on top of carriage

12..hub of feed lever

13..oil balls on apron front

Weekly apply grease to:

2…teeth of change gears
5…rack over entire length

11..tailstock quill over entire length

Fig 22

Fig 23

8.2 Bearing adjustment

The main spindle taper roller
bearings are adjusted at the factory.
If end play becomes evident after
considerable use the bearings may
be adjusted.

Loosen set screw (1, Fig 24) in the
slotted nut (2) on the back of the
spindle.

Fig 24

Tighten nut carefully, the spindle
should still revolve freely. Excessive
preloading will damage the bearings.

Tighten set screw.

8.3 Cross and top slide
adjustment

Each slide is fitted with a gib strip
and can be adjusted with screws (1,
Fig 25) fitted with lock nuts (2).

Fig 25

Adjust until slides moves freely
without play.

8.4 Cross slide spindle

adjustment

Remove the top slide and adjust the
grub screw (1, Fig 26) until the
backlash between the spindle and
the nut is eliminated.

Fig 26

10

8.5 Top slide spindle adjustment

Remove the spindle bracket as
shown.
Adjust the screw ring (1, Fig 27)
until all backlash has been
eliminated.

Fig 27

8.6 Spindle end float adj.

Loosen screw (1, Fig 28) and nut
(2).
Adjust the nut until all play has been
taken up.
Lock the nut with the screw.

Fig 28

8.7 Halve nut adjustment

Loosen two nuts (1, Fig 29) on the
right side of the apron and adjust the
control screws (2) until both halve
nuts move freely without play.
Tighten screws and nuts.

Fig 29

8.8 Shear pin replacement

If the shear pin breaks it must be
replaced (A, Fig 30).

Fig 30

Knock out the broken pin.
Line up the holes and fit the new pin.

9. Trouble shooting
Motor doesn’t start

*No electricity­check mains and fuse.

*Defective switch, motor or cord­consult an electrician.

Machine vibration

*Unbalanced work piece­Reduce spindle speed.

*Work piece deflection­improve chucking length or
diameter, support on tailstock end.

*Tool deflection­reduce tool length.

*Slide backlash­adjust slide gibs.

*Slides running dry­lubricate with oil.

*Dull tool tip­resharpen or change tool.

*Chip load too high­reduce depth of cut or feed-

Tool tip burns

*Cutting speed too high­reduce spindle speed.

*Dull tool tip­resharpen tool tip.

Machine turns a taper

*Tailstock alignment is offset­align tailstock position.

*Machine bed is twisted­supporting surface must be flat.

No automatic power feed

*Shear pin has broken­replace shear pin

10. Environmental protection

Protect the environment.
Your appliance contains valuable

materials which can be recovered or
recycled. Please leave it at a
specialized institution.

11. Available accessories

Stock number 321374

Machine base

Stock number 465302

Live centre MT-2

Stock number 708343K

13mm Drill chuck with MT-2 arbor