Page 1
1601 J. P. Hennessy Drive, LaVergne, TN USA 37086-3565 615/641-7533 800/688-6359 Manual Part No.: 911005 51
HENNESSY INDUSTRIES INC. Manufacturer of AMMCO
®
, COATS®and BADA®Automotive Service Equipment and Tools. Revision: 10/12
3000, 4000,
4100, 7500
Drum & Disc
Brake Lathes
®
Installation Instructions
Operating Instructions
Safety Instructions
Maintenance Instructions
READ these instructions before placing unit in
service. KEEP these and other materials delivered
with the unit in a binder near the machine for
ease of reference by supervisors and operators.
Page 2
ii • AMMCO Drum & Disc Brake Lathes
Safety
Table of Contents
Definitions of Hazard Levels . . . . . . . . . . . . .ii
Owner’ s Responsibility . . . . . . . . . . . . . . . .ii
Safety Notices and Decals . . . . . . . . . . . . . .iii
Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iii
Cautions and Dangers . . . . . . . . . . . . . . . . . . . . . .iii
Important Safety Instructions . . . . . . . . . . .iv
Before You Begin
Receiving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Electrical Requirements . . . . . . . . . . . . . . . . . . . .1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Operating Specifications . . . . . . . . . . . . . . . . . . . .2
Principle Operating Parts . . . . . . . . . . . . . . . . . . . .3
Arbor Installation . . . . . . . . . . . . . . . . . . . . . . . . . .4
Adapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Basic Operation
Spindle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Spindle Feed . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Spindle Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Spindle Speed Adjustment . . . . . . . . . . . . . . . . . .4
Crossfeed . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 - 5
V-belt Tension and Adjustments . . . . . . . . . . . . . .5
Poly V-belt Tension . . . . . . . . . . . . . . . . . . . . . . . .5
Basic Operation of Handwheels . . . . . . . . . . . . . .5
Reconditioning Brake Drums
Prepartion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Mounting Drums . . . . . . . . . . . . . . . . . . . . . . .6 - 8
Reconditioning Disc Brake Rotors
Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Twin Cutters . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Model 6950 Twin Cutter - 4000 & 7500 . . . . . . . .8
Rotor Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Set Up and Reconditioning Rotors . . . . . . . .10 - 11
Model 7900 Twin Cutter - 4100 . . . . . . . . . . . . .12
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Rotor Mounting . . . . . . . . . . . . . . . . . . . . . . . . . .12
Set Up and Reconditioning Rotors . . . . . . . . . . .13
Maintenance and Service
Oiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Care of Arbors and Adapters . . . . . . . . . . . . . . . .15
Shear Gear Replacement . . . . . . . . . . . . . . . . . .15
Definitions of Hazard Levels
Identify the hazard levels used in this manual with the
following definitions and signal words:
DANGER
Watch for this symbol:
It Means: Immediate hazards, which will result in
severe personal injury or death.
WARNING
Watch for this symbol:
It Means: Hazards or unsafe practices, which could
result in severe personal injury or death.
CAUTION
Watch for this symbol:
It Means: Hazards or unsafe practices, which may result
in minor personal injury or product or property damage.
Watch for this symbol! It means BE ALERT! Your
safety, or the safety of others, is involved!
Owner’s Responsibility
To maintain machine and user safety, the responsibility
of the owner is to read and follow these instructions:
• Follow all installation instructions and make sure
installation conforms to all applicable Local, State,
and Federal OSHA Regulations and Electrical Codes.
• Carefully check the unit for correct initial function.
• Read and follow the safety instructions. Keep them
readily available for machine operators.
• Make certain all operators are properly trained, know
how to safely and correctly operate the unit, and are
properly supervised.
• Allow unit operation only with all parts in place and
operating safely.
• Carefully inspect the unit on a regular basis and perform all maintenance as required.
• Service and maintain the unit only with authorized or
approved replacement parts.
• Keep all instructions permanently with the unit and all
decals/labels/notices on the unit clean and visible.
• If ownership of the unit is transferred, provide new
owner all information, manuals, and provide AMMCO
new ownership information.
DANGER
WARNING
CAUTION
Page 3
AMMCO Drum & Disc Brake Lathes • iii
Safety
Safety Notices and Decals
For your safety, and the safety of others, read and
understand all of the safety notices and decals included here and on the unit.
Read entire manual
before installing,
operating, or servicing this equipment.
Proper maintenance
and inspection is
necessary for safe
operation.
Do not operate a
damaged lathe.
Warning
This equipment incorporates parts such as snap
switches and power receptacles which tend to produce arcs or sparks. Therefore, when located in a
service facility, the unit should be in a room or enclosure provided for the purpose, or should be at least
18” or more above floor to minimize the risk of igniting fuel vapors.
Cautions and Dangers
1. Eye and face protection requirements:
“ Protective eye and face equipment is required
to be used where there is a reasonable
probability of injury that can be prevented by use
of such equipment.” OSHA 1910.133 (a).
Protective goggles, safety glasses, or a face
shield must be provided by the purchaser/user
and worn by the operator of the equipment.
Make sure all eye and face safety precautions are
followed by the operator(s). Keep bystanders out
of the area.
2. Do not remove any safety equipment, belt
guards, or shortcut controls or operations.
3. Make sure drums and rotors are properly and
squarely mounted before starting lathe, and that
all parts are secure.
4. Do not wear loose clothing, jewelry, or gloves
when operating or working around a lathe.
5. Do not overload the lathe. Read and understand
the lathe specifications. Overloading is poor
machine tool practice, shortens the life of the
lathe, and could cause a failure resulting in
personal injury.
Failure to follow danger, warning, and caution
instructions may lead to serious personal injury or
death to operator or bystander or damage to property. Do not operate this machine until you read
and understand all the dangers, warnings and cautions in this manual. For additional copies of either,
or further information, contact:
Hennessy Industries, Inc.
1601 J.P. Hennessy Drive
LaVergne, TN 37086-3565
(615) 641-7533 or (800) 688-6359
www.ammcoats.com
WARNING
1. Read and follow instructions.
2. Always wear eye protection, avoid loose
clothing and jewelry.
3. Keep all guards, shields, and covers in place and
in working order.
4. Keep bystanders out of work area.
5. Unplug unit from power source before servicing
or adjusting.
6. Maintain unit properly, keep work surfaces and
work area clean.
CAUTION
Prevent accidents and injury,read and follow instructions.
Page 4
iv • AMMCO Drum & Disc Brake Lathes
READ ALL INSTRUCTIONS
When using your garage equipment, basic safety precau-
tions should always be followed, including the following:
1. Keep guards in place and in working order.
2. Remove adjusting keys and wrenches from the tool
before turning it on. Make this a habit.
3. Keep work area clean. Cluttered areas and benches
invite accidents.
4. Avoid dangerous operating environments. Do not use
power tools in areas where explosive vapors are present or in
damp of wet locations. Do not expose them to rain. Keep the
work area clean and well lighted.
5. Keep children away. All bystanders should be kept com-
pletely away from the work area.
6. Make the workshop kid-proof. Use padlocks and master
switches, and remove starter keys.
7. Don’ t force a tool. It will do the job better and safer at
the rate for which it was designed.
8. Use the right tool. Don’ t force a tool or an attachment
to do a job for which it was not designed.
9. Dress properly. Keep loose clothing, gloves, neckties,
shop rags or jewelry may get caught in moving parts. Non-slip
footwear is recommended. Wear protective hair covering to
contain long hair.
10. Wear eye protection. Safety glasses, goggles, or a
face shield will help protect the operator from injury. Use a
face shield and dust mask during dusty operations.
11. Secure the work properly to the unit for setup and tool
bit positioning. Do not attempt to hold a drum or rotor steady
on the arbor with your hands. Both hands must be free to
operate unit.
12. Don’ t overreach. Keep proper footing and balance at
all times when lathe is in operation or when working around
the unit.
13. Maintain tools with care. Keep tools sharp and clean
for best and safest performance. Follow instructions for lubricating and changing accessories.
14. Remove power from the unit and disconnect tools
before servicing and when changing accessories such as
blades, bits, cutters, etc. Follow lock-out and tag-out procedures as required.
15. Avoid unintentional starting. Make sure the switch is in
the OFF (O) position before plugging the machine in or performing any maintenance or service work.
16. Use recommended accessories. Consult the manufacturer’ s catalogs for recommended accessories. Use of
improper accessories may cause risk of injury to operator or
bystanders.
17. Never stand or lean on a lathe. Serious injury could
occur if the lathe is tipped or if the cutting tool is unintentionally contacted.
18. Check damaged parts carefully. Before further use of
the lathe, a guard or other part that is damaged should be
carefully checked. Immediately replace all damaged, missing,
or non-functional parts. Check for alignment of moving parts,
binding of moving parts, breakage of parts, mounting, and any
other conditions that may affect operation. Guards and other
parts that are damaged should be properly repaired or
replaced before lathe is used again.
19. Always feed the work into a blade or cutter and against
the direction of rotation. Cutters and tool bits are designed to
cut from the inside of a drum or rotor to the outer edge. Do
not attempt to cut from the outside edge in to the center.
20. Never leave tools running unattended. Turn the power
off. Don’ t leave the tool until it comes to a complete stop.
21. Never use compressed air to blow the tool clean. Chips
and dust may be driven between machined parts and into
bearings, causing undue wear. They may also contact persons in the area causing personal injury.
22. Operate the lathe in the proper environment. The lathe
incorporates parts such as snap switches and power receptacles which tend to produce arcs or sparks. Therefore, when
located in a garage,the unit should be in a room or enclosure
provided for the purpose, or should be at least 18” or more
above the floor to minimize the risk of igniting fuel vapors.
Before operating the lathe, review the warning information on the lathe and the cautions, warnings and dangers in this manual. Also review the following general safety instructions. Failure to follow safety instructions could result in personal injury to
operator or bystanders and damage to the lathe or personal property.
IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
Page 5
AMMCO Drum & Disc Brake Lathes • 1
Before You Begin
Receiving
The shipment should be thoroughly inspected as
soon as it is received. The signed bill of lading is
acknowledgement by the carrier of receipt in good condition of shipment covered by our invoice.
If any of the goods called for on this bill of lading are
shorted or damaged, do not accept them until the carrier makes a notation on the freight bill of the shorted
or damaged goods. Do this for your own protection.
NOTIFY THE CARRIER AT ONCE if any hidden loss or
damage is discovered after receipt and request the carrier to make an inspection. If the carrier will not do so,
prepare a signed statement to the effect that you have
notified the carrier (on a specific date) and that the carrier has failed to comply with your request.
IT IS DIFFICULT TO COLLECT FOR LOSS OR DAMAGE AFTER YOU HAVE GIVEN THE CARRIER A
CLEAR RECEIPT.
File your claim with the carrier promptly. Support your
claim with copies of the bill of lading, freight bill,
invoice, and photographs, if available.
Although AMMCO’ s responsibility ceases upon
delivery of the shipment to the carrier, we will gladly
assist in tracing lost shipments. Our willingness to
assist in every possible manner does not make
AMMCO responsible for collection of claims or
replacement of lost or damaged materials. Shipping
damage claims will not be handled under warranty.
Electrical Requirements
The lathe must be properly grounded to protect the
operator from shock. The lathe is equipped with an
approved 3-conductor cord and a 3-prong grounding
type plug to fit the proper grounding-type receptacle.
Should an extension cord be required, use 3-conductor
cords with 3-prong grounding plug and 3-prong grounding receptacle properly rated to handle this electrical
power tool only. Do not modify a cord or plug to match
a receptacle; have a qualified electrician install an
appropriate outlet to match the lathe requirements.
Repair or replace any worn or damaged power cords
immediately.
Verify that the lathe plug and grounding-type receptacle match as shown in Figure 1.
Figure 1 - Power Cord Plug and Receptacle Types
Installation
1. Assemble bench according to the instructions pro-
vided. Tighten all fasteners securely.
2. After assembly, the bench should be leveled and
may be bolted down with 3/8 or 7/16 inch bolts or lag
screws.
3. Unbolt the lathe from the shipping pallet. Lift the
lathe onto the bench.
4. Bolt the lathe to the bench with the hardware provided. Tighten fasteners securely.
5. Remove any packing materials and protective
wrapping from the lathe and components.
6. Make sure lathe is turned off. Plug lathe into a
properly installed and grounded outlet that matches the
lathe plug.
7. Remove the shipping plug, insert the oil dipstick,
and check oil level. The lathe is shipped with the correct amount and type of oil. Add oil as necessary to
reach the correct mark on the dipstick. Use only EP-8090 gear oil. Oil level should be checked often.
Figure 2 – Check oil level
8. Clear the area and turn lathe on. Check for proper
operation (motor and spindle rotation).
Preparation for Use
1. Inspect all adapters and accessories for burrs,
nicks, or other damage.
2. Clean accessories with a vaporizing solvent.
3. Apply a light film of oil to all adapters to protect
their machined surfaces from rust. Refer to the maintenance section for more information.
There is a circuit breaker located on the electrical panel to prevent damage to the lathe
in the event the motor is overloaded. Move
the switch to the off position and correct
overloading situation before re-setting circuit breaker. Serious personnal injury could
result if circuit breaker is re-set while lathe is
still on.
WARNING
115 VAC 230 VAC
Page 6
2 • AMMCO Drum & Disc Brake Lathes
Operating Specifications
3000 4000 4100 7500
Overall lathe height 17.25” (438 mm) all models
Lathe shipping weight 325 lbs (147 kg) 385 lbs (175 kg) 410 lbs (186 kg) 367 lbs (167 kg)
Floor space requirements - width 48” (1219.20 mm) all models
Floor space requirements - deep 34.5” (901.70 mm) all models
Spindle to floor (mounted on optional bench) 39.375” (1000 mm) all models
Electrical requirements Standard: 115 VAC, 60 Hz, single-phase, fused at 15 amps (all models)
(unless otherwise specified) Optional: 230 VAC, 60 Hz, single-phase, fused at 6.3 amps (all models)
Spindle motor 1 HP, 60 Hz, 115/230 VAC (all models)
Spindle travel 6.875” (175 mm) 6.875” (175 mm) 9.875” (251 mm) n/a
Spindle speed
Inner Groove 100 RPM 100 RPM 60 RPM 100 RPM
Middle Groove _ _ 80 RPM _
Outer Groove 200 RPM 200 RPM 115 RPM 200 RPM
Spindle feed speed Infinitely variable
Minimum 0.002 inch per revolution (0.05 mm/rev) except 7500 n/a
Maximum 0.020 inch per revolution (0.50 mm/rev) except 7500 n/a
Cross feed speed
Fine Manual 0.002 0.002 0.002
Course Manual 0.010 0.010 0.010
Handwheel graduations 0.002 (0.050 mm) all models
Maximum brake rotor diameter* 14.5” (368.3 mm) all models
Maximum brake rotor thickness 1.875” (47.63 mm) 4” (102 mm) 1.875” (47.63 mm)
Brake drum diameter
Minimum 6” (152 mm) (except 7500) n/a
Maximum 28” (711 mm) (except 7500) n/a
Maximum drum depth 6.875”
(175 mm) 6.875” (175 mm) 9.875” (251 mm) 9.875” (251 mm) n/a
Maximum load
1” Arbor 100 lbs. (45.36 kg) all models
1.875” Arbor 200 lbs. (90.72 kg) all models
* The no. 906936 Cross Feed Extension – for use with the 4000, 4100 and 7500 lathes only
– increases the maximum rotor diameter to 19” (483 mm).
Page 7
AMMCO Drum & Disc Brake Lathes • 3
Work Light
1” Arbor
Shield
Twin Cutter
Boring Bar and
Boring Bar Clamp
Cross Feed Lock
Cross Feed
Handwheel
Power Cord
Spindle Feed Handwheel
Spindle Feed Dial
Spindle Feed
Engaging Lever
Spindle Lock
Oil Dipstick
Grease Fitting
Cross Feed
Engaging Lever
Cross Feed
Gearbox
V-Belt & Speed
Adjusting Lever
Belt Tension
Adjusting Nut
ON/OFF Switch
Infimatic
®
Variable
Feed Gearbox
Assembly
Draw Bar
Drive Motor
Pulley Guard
Principle Operating Parts
Hazard Areas must be protected during
lathe operation. Keep shields and guards
in place. Keep fingers out of these areas
and away from rotating parts.
WARNING
Page 8
4 • AMMCO Drum & Disc Brake Lathes
Arbor Installation
The 1” arbor shipped with the lathe has been carefully matched to the lathe during final assembly and
testing. Witness marks have been etched onto the
arbor and the spindle for precise, repeatable alignment.
The witness marks must be carefully aligned when
installing the arbor (Figure 3). A true-running arbor is
essential to professional quality brake drum and rotor
reconditioning.
1. Locate the witness marks on the arbor and the
spindle.
Figure 3 – Align witness marks during arbor installation
2. Insert the arbor into the spindle making sure the
witness marks are aligned.
3. Tighten the drawbar (located at the rear of the
spindle) to pull the hardened and ground tapers of the
arbor into the matching seats in the spindle.
Adapters
Important: Although the adapters, arbor, and spindle
are made of top grade steel and are turned, hardened,
and precision ground to close tolerances, great care
should be taken in their use, handling, and storage.
Even the smallest nick, scratch, or loose chip on the
machined mating surfaces can cause incorrect rotor
mounting alignment. This will cause inaccurate machining.
Figure 4 – Use care to avoid damaging mating surfaces
Always inspect the surface, face, and seating tapers
of each part before use. Wipe each part clean before
and after using it. Carefully correct any flaw with a fine
stone. If damage cannot be corrected, replace the part.
Basic Operation
To completely understand drum and rotor turning you
must have a knowledge of the lathe itself.
Spindle
The spindle is a motor driven shaft that turns the
arbor upon which the brake drum or rotor is mounted.
By turning the drum and holding a cutting tool against
the inner braking surface, metal can be removed.
Do not try to move any feed levers or dials
without the drive motor running. Damage
may occur to the gear trains.
Spindle Feed
By operating the spindle feed lever, the spindle will
move the mounted brake drum to the left. This feeds
the braking surface across the cutting tool as the drum
moves away from the tool. Spindle feed may also be
done manually using the spindle feed handwheel.
Spindle feed refers to the distance the spindle is
pulled per revolution. This speed is adjustable on all
models except the 7500:
Important: Spindle feed must be adjusted with the
lathe running.
1. Rotate the spindle feed dial to the desired feed
rate. The rate is adjustable to any point between
0.002” (0.05 mm) and 0.020” (0.50 mm).
Spindle Speed
Spindle speed is measured in RPMs and is adjustable.
Refer to the specifications listed on page 4 for the RPM
rating of each grove on the V-belt pulley for each
model.
Spindle Speed Adjustment
This V-belt adjustment must be made with the lathe
off.
1. Release the belt tension by moving the V-belt
adjusting lever to the right (clockwise).
2. Move the belt to the pulley groove that will give
the correct spindle speed for the cut to be taken.
3. Reapply tension to the V-belt by moving the
adjusting lever back to the operating position.
Cross Feed
The cross feed draws the tool bit across the face of a
brake rotor or flywheel when the cross feed drive is
engaged (models 4000, 4100, and 7500). The cross
feed may also be operated manually using the cross
feed handwheel (all models).
Feed speed refers to the thousandths of an inch the
cutting tools move per revolution of the spindle. The
CAUTION
Arbor
Keep the arbor tapers and seats clean
Witness Marks
Typical Inner & Outer Adapters
Seating Tapers
Machined Surfaces
Page 9
AMMCO Drum & Disc Brake Lathes • 5
cross feed speed is adjustable on the 4000, 4100, and
7500:
1. Using the 3-position lever, select Fine (0.002”
[0.05 mm]) or Coarse (0.010” [0.25 mm]). The Neutral
position is the off position (no movement). The cross
feed may also be operated manually.
V-Belt Tension and Adjustment
A loose belt can cause slippage when taking heavy
cuts. A belt that is too tight can cause vibration and
possible sub-standard finishes on machined drums and
rotors. Check and adjust belt monthly.
There should be between 14” to 12” of play in the belt.
1. Position the v-belt speed adjusting lever to the left
(counterclockwise) to the fully engaged position.
2. Loosen the adjustment nut.
Figure 5 – Engage lever and loosen nut
3. Push in on the belt approximately 14” to 12”
(0.64 to 12.7 mm) and hold.
Hazard Areas must be protected during lathe operation. Keep shields and guards in place. Keep fingers
out of these areas and away from rotating parts.
4. Retighten the adjusting nut.
Figure 6 – Press the belt in and tighten adjusting nut
Poly V-Belt Tension
For poly v-belt adjustment, use the same procedure
as for the standard v-belt, with these exceptions:
1. The poly v-belt should be adjusted to deflect 332”
with a 5 pound push on the belt. The ideal tension is
the lowest tension at which the belt will not slip under
the highest load.
2. Check and adjust as required the tension during
the first day of operation. Do not overtighten.
Basic Operation of Handwheels
Clockwise rotation of the spindle feed handwheel
retracts the spindle in towards the lathe.
Clockwise rotation of the cross feed handwheel
moves the cutting tool in towards the lathe.
Figure 7 – Clockwise rotation of handwheels
Counterclockwise rotation of the spindle feed hand-
wheel extends the spindle out away from the lathe.
Counterclockwise rotation of the cross fee hand-
wheel moves the cutting tool out away from the lathe.
Figure 8 – Counterclockwise rotation of handwheels
WARNING
V-belt
Adjustment Nut
Speed Adjusting Lever
Push in
1
⁄4” to1⁄2”
Spindle Feed
Handwheel
Cross Feed
Handwheel
Spindle rotates when
motor is turned on.
Spindle Feed
Handwheel
Cross Feed
Handwheel
Page 10
6 • AMMCO Drum & Disc Brake Lathes
Reconditioning Brake
Drums
Preparation
1. Measure the diameter of the brake drum with a
brake drum micrometer.
Figure 9 – Measure drum diameter
2. Determine if the drum will be within maximum
rebore limits after reconditioning.
Note: Most often, the DISCARD diameter is cast into
the brake drum, not the maximum machining diameter.
3. Inspect brake drum. Do not attempt to machine a
drum that is damaged or in poor condition.
Mounting Drums
1. Loosen the boring bar clamp nut and push the bor-
ing bar all the way into the clamp.
2. Mount the drum on the arbor using the proper
adapters, cones, and spacers. Use examples in Figure
10 for guidance.
3. Wrap the drum silencer band snugly around the
drum. Be sure it covers up to the right-hand edge.
Figure 11 – Attach silencer band
Important: The spindle feed handwheel will not oper-
ate unless the spindle feed engagement lever is in the
OFF position. Feed should only be adjusted when the
spindle is turning.
4. Position the cross slide and spindle by turning their
respective handwheels to their maximum clockwise (in)
position. Then back off the cross feed handwheel 2 complete turns and the spindle handwheel 4 complete turns.
Figure 10 – Typical drum mounting configurations
Hubbed Brake Drums
A
C
B
L
K
D
F
Tapered cone adapters fit in the bearing seats, making contact near the middle of the bearing race whenever possible
rather than near an edge. Various adapters and spacers may
be used to fill out the shaft of the arbor.
Hubless Brake Drums
A
C
B
E
H
D
F
A cone fits into the center hole of the drum from the inside
to center the drum on the arbor. Select a hubless adapter
which will fit inside the drum, against the flat lug hole surface and either straddle the bolt holes to avoid mounting
against a burr, or remove the burrs. Slip the hubless
adapter onto the arbor followed by a spring, the cone, the
drum, and another hubless adapter. Fill out the shaft with
spacers as needed.
J
I
G
Key to Mounting Adapters, Cones, and Related Parts
A. 1” Arbor G. Spring
B. Arbor Nut H. Inside Floating Adapter (sm.)
C. Self-Aligning Spacer I. Outside Floating Adapter (lg.)
D. Lathe Spindle Nose J. Centering Cone
E. Spacer K. Large Double Taper Adapter
F. Protective Boot L. Small Double Taper Adapter
Note: The self-aligning spacer should always be used next
to the arbor nut when tightening. To avoid overtightening,
wrench tighten the arbor nut counterclockwise until the
drum and adapters begin to turn on the arbor, then continue to advance the wrench
1
16 of a turn. DO NOT over-
tighten the arbor nut.
Arrows for reading scale
Dial
Buckle Finger
Silencer Band for Drums
Page 11
AMMCO Drum & Disc Brake Lathes • 7
5. Position the boring bar by loosening the boring bar
clamp nut and sliding the boring bar inward toward the
drum until the tool bit is close to the drum.
The boring bar position is changed whenever a drum
of different diameter is machined.
The entire boring bar clamp may also be swiveled to
achieve the best cutting position.
Figure 12 – Positioning the boring bar
6. Turn the drum by hand to make sure that everything is clear.
7. Turn the lathe ON.
8. Advance the tool bit manually until it just contacts
the drum surface momentarily and makes a scratch
cut.
Figure 13 – First scratch cut
9. Loosen the dial lock screw on the cross feed handwheel and set the dial to the diameter of the drum as
measured with the micrometer. Tighten the lock
screw.
This setting will be the reference used to help deter-
mine the drum recondition diameter.
Figure 14 – Set drum diameter measurement
10. Back the tool bit off and turn the lathe OFF.
11. Loosen the arbor nut, rotate the drum 12 turn
(180°) on the arbor and inner adapter, and retighten the
nut.
12. Turn the lathe ON.
13. Turn the spindle feed handwheel 12 turn in
either direction and make a second scratch cut.
Figure 15 – Second scratch cut
14. Turn the lathe OFF.
15. Examine the scratch cuts.
If the first and second cuts are opposite one another
(180° apart), remove the drum from the arbor, check
the mounting adapters and arbor for nicks, burrs, or
chips, remount the drum, and repeat scratch cut
process.
If the scratches are side by side, proceed to step 16.
16. Turn the spindle feed handwheel until the deepest worn groove of the drum lines up with the point of
the tool bit.
17. Advance the tool bit into the bottom of the
groove by rotating the cross feed handwheel counterclockwise.
Note: These operations may be done with the lathe
running.
The depth of cut dial will show the approximate
reconditioned diameter of the drum. This measurement must be compared with:
A. The maximum rebore limits cast into the drum.
B. The measured diameter to determine the best
amount of material to be removed in one pass.
18. Determine the depth-of-cut by these general
guidelines:
• Roughing cuts should be no deeper than 0.020” .
• Finish cuts should be no shallower than 0.004”
deep.
19. With the lathe running, set the depth-of-cut dial
to the depth desired and lock the cross feed by tightening the lock knob.
First
Scratch Cut
Dial Lock
Screw
Second
Scratch Cut
Page 12
8 • AMMCO Drum & Disc Brake Lathes
Figure 16 – Lock cross feed
20. Set the spindle feed speed while the lathe is running by unlocking the feed dial lock screw and turning
the dial. Tighten the lock screw when speed is set.
The rough cut feed range is between 0.006” (0.15
mm) (6 on the dial) to 0.020” (0.50 mm) (20 on the
dial).
The finish cut feed range is between 0.002” (0.05
mm) (2 on the dial) and 0.006” (0.15 mm) (6 on the
dial).
21. Set the feed shut-off by sliding it on the shaft to
a point that approximately equals the depth of the drum
and tightening it in place. The feed will stop when it
reaches this point.
Figure 17 – Set spindle feed shut-off
22. Engage the feed lever to begin drum reconditioning.
Reconditioning Disc Brake
Rotors
Preparation
1. Inspect the rotor carefully for scoring, rust ridges
(at the inner and outer circumference of the rotor), and
hard spots. Any excessive wear or deformity should be
noted and, if not within acceptable limits, the rotor
should be replaced.
2. Use a micrometer to check the thickness of the
rotor at no less than 3 points around the circumference
about 1” (2.54 mm) in from the outer diameter.
If the rotor thickness varies between readings, it
should be reconditioned. However, if the thickness is
less than the minimum established by the manufacturer, or if it will be less after reconditioning, the rotor
should be replaced.
Note: Most often
the DISCARD thickness dimension is
cast or stamped
into the rotor, not
the minimum
machine-to thickness.
Figure 18 – Measure rotor thickness
Twin Cutters
A twin cutter tool is used on the 4000, 4100, and
7500 to recondition both surfaces of a brake rotor at
the same time. The twin cutter replaces the boring bar
on top of the cross feed after removing the upper and
lower tool bar clamps.
Model 6950 Twin Cutter—4000 & 7500
1. Mount the twin cutter on the cross feed with the
stud bolt extending through the cast slot. The slot
helps center the twin cutter to the rotor.
2. Secure the twin cutter to the cross feed with selfaligning nut and washer assembly. Tighten the nut
firmly.
Figure 19 – Install the twin cutter
Cross slide self-aligning nut/washer
Twin cutter
Cross slide self-aligning nut/washer
Upper and lower
boring bar clamps
Cross Feed Lock
Knob
Feed shut-off
Spindle feed lever
Spindle feed dial
Feed dial
lock screw
Page 13
AMMCO Drum & Disc Brake Lathes • 9
J
A
D
E
G
C
B
A
H
F
E
G
C
B
F
A
J
I
A
K
C
B
J
A
A
B
C
G
F
H
E
I
C
B
E
F
H
F
B
C
G
E
A
H
G
C
B
A
A - 1” Arbor
B - Arbor Nut
C - Self-Aligning Spacer
D - Spacer
E - Spring
F - Small Hubless Adapter
G - Large Hubless Adapter
H - Centering Cone
I - Small Double Taper Adapter
J - Large Double Taper Adapter
K - Adapter, Used as Spacer
Rotor Mounting
Review the descriptions of mounting a brake drum on
page 6. The same directions apply when mounting a
brake rotor. Hubbed rotors are mounted on adapters
that fit into the bearing races. Hubless rotors use a
cone in the center hole and a hubless adapter on each
side of the rotor. Spacers are used to fill out the arbor
shaft so that the arbor nut can be tightened. The
setups illustrated in Figure 20 are typical of the many
mounting configurations necessary to meet the
requirements of brake rotor reconditioning. The
adapters, cones, and spacers supplied with the lathe
will allow reconditioning of the majority of the rotors
found on current production vehicles. Optional
adapters, cones, and spacers are available to meet special needs.
Note: Adapters may also be used as spacers to fill out
the arbor shaft if care is taken to prevent damage to
their machined surfaces.
The patented self-aligning spacer prevents diagonal
thrust on t he adapters. The self-aligning spacer should
always be used adjacent to the arbor nut.
C
I
B
H
Page 14
10 • AMMCO Drum & Disc Brake Lathes
Set Up and Reconditioning Rotors
1. Install a silencer band on the mounted rotor.
Stretch the band around the rotor and hook the metal
loop over a lead weight.
Figure 21 – Attach silencer band
Always wear safety glasses or a face shield. Cutting
or grinding on an exposed surface such as a rotor
will produce flying chips and debris.
Hazard Areas must be protected during lathe operation. Keep shields and guards in place. Keep fingers
out of these areas and away from rotating parts.
2. Center the twin cutter to the rotor. Loosen the
stud nut and adjust the twin cutter so that the rotor is
centered between the tool bits. The slot of the twin
cutter should be approximately parallel to the lathe
spindle. Tighten the stud nut firmly.
Figure 22 – Center the twin cutter
3. Install the safety shield. Review the cautions and
dangers section and the general safety information at
the beginning of this manual. The safety shield is easily screwed onto the twin cutter in the threaded mounting hole provided.
Figure 23 – Attach the safety shield
4. Adjust the drive belt to match the rotor size. Use
the outer pulley groove for passenger car and most
light duty truck rotors. Choose one of the inner pulley
grooves when machining medium duty and larger truck
rotors and some solid rotors.
Figure 24 – Adjust drive belt location
5. Make sure that the tool bits clear the rotor surfaces and the silencer band. Give the rotor a full turn by
hand and watch for clearance all the way around.
6. Turn the lathe ON.
7. Turn each tool bit control (the outer knurled knobs)
clockwise until the tool bits just contact the rotor surfaces.
8. When the tool bits make contact, rotate each of
the inner depth-of-cut collars to zero and back the tool
bits away from the rotor.
From this point on, all tool adjustments will be made
with the tool bit controls. Then inner depth-of-cut collars will be the reference and should not be moved.
Figure 25 – Tool bit controls
WARNING
Silencer band
Twin cutter
Stud nut
Tool bits
Safety shield
Twin cutter
V-belt in outer pul-
ley groove
Inner depth-ofcut collars
Tool bit controls
Hold knob with one hand
– turn collar
Each increment =
0.002” english,
0.05 mm metric
Page 15
AMMCO Drum & Disc Brake Lathes • 11
9. Turn the cross feed handwheel until the tool bits
are at mid-point of the rotor face.
10. Turn the left hand tool bit control until the tool bit
contacts the rotor surface and makes a scratch cut.
After the cut is made, back the tool bits off and turn the
lathe OFF.
Figure 26 – First scratch cut
The scratch will usually appear as an incomplete circle. This is caused by runout or wobble due to rotor
condition, or by the way the rotor is mounted on the
arbor.
11. Check rotor mounting by loosening the arbor nut
and turning the rotor 180° by hand on the arbor. Make
sure the inside adapter does not rotate along with the
rotor. Then retighten the arbor nut, turn the cross feed
handwheel back 1/2 turn, turn the lathe ON, and repeat
step 10 to make a second scratch cut.
Figure 27 – Rotate rotor 180°
Figure 28 – Second scratch cut
12. If the scratch cuts are side-by-side, the runout or
wobble is caused by rotor condition. A dial indicator
may be used to compare rotor runout with manufacturer’ s specifications.
Figure 29 – Using a dial indicator
13. If the scratch cuts are opposite one another
(180°), the rotor may not be properly mounted on the
arbor. Remove the rotor and examine the arbor and all
adapters for nicks, burrs, chips, dirt, or rust. Inspect the
rotor hub for loose or damaged bearing cups. Clean,
repair, remount, or replace as necessary.
14. Recheck the setting of the depth-of-cut collars
which were set to zero earlier by moving the tool bits
inward until they just contact the surfaces of the rotor.
The collars should be at zero. Reset the collars if necessary.
15. Turn the cross feed handwheel clockwise until
the tool bits are near the rotor hub.
16. Turn the lathe ON.
17. Turn both tool bit controls to the desired depth-
of-cut and lock them in position by tightening the red
lock knobs above the tool bits.
Note: Either rough or finish cuts may be taken to
resurface a rotor. Generally, finish cuts should be
0.004” (0.10 mm) to 0.006” (0.15 mm) per side. Very
shallow cuts of less than 0.004” (10 mm) per side tend
to reduce tool bit life because the heat generated during reconditioning isn’ t transferred to the rotor efficiently. Rough cuts may be taken from 0.006” to
0.010” per side.
18. Engage the automatic cross feed by moving the lever to the desired
speed. The cross feed will
stop automatically when
the cutting tools have
moved all the way across
the face of the rotor.
Note: For roughing cuts,
move the cross feed lever
to the FAST position.
Figure 30 – Engage automatic cross feed
First scratch cut
Rotate rotor only 180°
Loosen arbor
nut, do not turn
inside adapter
Second
scratch cut
Scratch cuts opposite
each other
Dial indicator
Fast
Slow
Neutral
Page 16
12 • AMMCO Drum & Disc Brake Lathes
Model 7900 Twin Cutter – 4100
The 7900 twin cutter mounts on the cross feed tool
post to resurface both rotor surfaces simultaneously.
Each tool bar is individually adjustable (in thousandths
of an inch or millimeters) to permit precise depth-of-cut
settings.
The tool bars mount on top of the tool bar support,
carbide tips up, and are used to recondition both brake
surfaces of a rotor at the same time.
Figure 31 – 7900 twin cutter controls
Installation
1. Remove the self-aligning nut/washer assembly
retaining the boring bar clamp.
2. Remove the clamp and boring bar.
Note: Older lathes have a tool post pivot screw which
must be loosened before the lower clamp can be
removed.
3. Place the tool bar support over the cross feed tool
post stud and replace self-aligning nut/washer assembly.
4. Align the tool bar support parallel with the arbor
and wrench tighten the nut.
Preparation
1. Inspect the rotor carefully for scoring, rust ridges
(at the inner and outer circumference of the rotor), and
hard spots. Any excessive wear or deformity should be
noted and, if not within acceptable limits, the rotor
should be replaced.
2. Use a micrometer to check the thickness of the
rotor at no less than 3 points around the circumference
about 1” (2.54 mm) in from the outer diameter.
If the rotor thickness varies between readings, it
should be reconditioned. However, if the thickness is
less than the minimum established by the manufacturer, or if it will be less after reconditioning, the rotor
should be replaced.
Note: Most often the DISCARD thickness dimension
is cast or stamped into the rotor, not the minimum
machine-to thickness.
Rotor Mounting
Follow the rotor mounting guidelines and examples
provided on pages 10 and 11 and mount the rotor on
the arbor.
Set Up and Reconditioning Rotors
1. Install a weighted silencer band on vented rotors,
a non-weighted silencer band on non-vented rotors, or
an optional friction rotor silencer to dampen vibrations
during machining.
2. Use the cross feed handwheel to position the tool
bar support about 12” from the rotor or silencer band.
3. Loosen the tool post nut and center the tool bar
support to the rotor. Wrench tighten the nut.
If the tool bar support cannot be centered with the
rotor by moving the tool bar support, it may be necessary to move the rotor in or out by using the spindle
feed handwheel to make the adjustment.
4. Install the tool bar, carbide tip up, on the right side
of the rotor slide with the T-bolt and clamp. Slide the
tool bar into the clamp.
5. Repeat step 4 for the left side tool bar.
6. Turn the end knob of each tool bar micrometer
counterclockwise to fully withdraw the tool bit holders.
7. Position the left tool bar approximately parallel to
the outer brake surface so that the tool bit is 1/8” away
from the brake surface and reaches to the groove at
the base of the brake surface. tighten the T-bolt nut.
8. Repeat step 7 for the right tool bar.
Figure 32 – Positioning the tool bars
9. Turn the cross feed handwheel counterclockwise
until the tool bits are about 12” in from the outer edge
of the brake surface.
10. Turn the lathe ON.
11. Turn the end knob on the left boring bar microm-
eter clockwise to advance the tool bit until it lightly contacts the outer brake surface and makes a scratch cut.
Inch/Millimeter
Micrometer Dials
Set to
0.004”
Set to
0.1 mm
Adjustment Knobs
Page 17
AMMCO Drum & Disc Brake Lathes • 13
12. Turn the lathe OFF.
13. If the tool bit did not scratch the brake surface
all the way around, there is runout in the rotor and/or
runout cause by improper rotor mounting. To determine if the runout is caused by improper mounting:
A. Turn the end knob on t he left tool bar
micrometer counterclockwise 1 full turn to back
the tool bit away from the brake surface.
B.Turn the rotor slide handwheel clockwise to
move the tool bit 14” toward the arbor.
C. Loosen the arbor nut and rotate the rotor 180°
on the arbor. Do not allow the adapters to turn.
Retighten the arbor nut.
D. Turn the lathe ON.
E. Turn the end knob on the left tool bar
micrometer clockwise until the tool bit makes light
contact with the brake surface. Turn the end knob
of the left tool bar micrometer counterclockwise
to withdraw the tool bit from the brake surface.
F. Turn the lathe OFF.
If the 2 scratch cuts are side-by-side, the runout is in
the rotor and not the mounting. Continue with step 14.
If the 2 scratch cuts are 180° apart, the runout is
caused by improper mounting. Remove the rotor and
adapters from the arbor, inspect the arbor and adapters
for nicks, burrs, chips, or rust, inspect the rotor bearing
races for looseness, clean all items, and remount the
rotor. Check for runout again. If runout is corrected,
continue to step 14.
Hazard Areas must be protected during
lathe operation. Keep shields and guards in
place. Keep fingers out of these areas and
away from rotating parts.
Figure 33 – Scratch Cuts
14. Turn the lathe ON.
15. Turn the end knob on the left tool bar microme-
ter clockwise until the tool bit lightly contacts the brake
surface.
16. Hold the end knob of the micrometer in place
and rotate the depth-of-cut dial to zero.
17. Turn the end knob on the right tool bar micrometer clockwise until the tool bit lightly contacts the
brake surface.
18. Hold the end knob of the micrometer in place
and rotate the depth-of-cut dial to zero.
Note: Once both depth-of-cut collars are set to zero,
use only the end knob to advance or withdraw the tool
bit. The collar will rotate with the knob to show the
depth-of-cut. Any other disturbance of the collar will
lose the zero position.
19. Turn the cross feed handwheel clockwise until
the outer tool bit reaches the groove at the rotor hub.
The right tool will automatically be positioned beyond
the inner brake surface.
20. Turn the end knob of each tool bar micrometer
individually to set each tool bit to the desired depth-ofcut. Remove only enough material to clean up each
side.
21. Engage the automatic cross feed to begin the
cut.
22. When the tool bits have cleared the rotor, disengage the cross feed and turn the lathe OFF.
23. Inspect the brake surfaces. If part of the surface
was not cut, leave the tool bars locked in position, turn
the lathe ON, slowly turn the cross feed handwheel
clockwise until the outer tool reaches the groove at the
rotor hub, and repeat steps 20, 21, and 22.
WARNING
Page 18
14 • AMMCO Drum & Disc Brake Lathes
Maintenance and Service
Before making any inspection, adjustment,
or repair, make sure lathe is turned OFF and
disconnect the power source.
Wear protective clothing, equipment and
eye protection when making any adjustments or repairs to the machine.
Oiling
The lathe is shipped from the factory with the correct
amount and type of oil. Check oil level frequently, and
refill as necessary with EP-80-90 gear oil.
Figure 34 – Oiling
After every 500 hours of use, drain the oil and refill to
the appropriate level on the dipstick with clean EP-8090 gear oil. Use the oil drain plug on the front of the
lathe to drain the old oil.
Figure 35 – Drain plug location
The Infimatic®Variable Feed Gearbox and the disc
brake feed mechanism assemblies are filled with a special lubricant and need no further internal lubrication.
Lubricate the cross feed once each month with an
automotive chassis grease. Pump the grease into the
fitting until clean grease comes out the relief slot at the
base of the fitting.
Use a hand pump grease gun only. A high pressure
gun can burst the lathe casting.
Figure 36 – Cross feed grease fitting
Grease the lead screw drive monthly. Locate the lead screw
drive by pulling the protective boot back.
Figure 37 – Lead screw drive
Oil exposed metal parts periodically to prevent rust.
WARNING
WARNING
Grease fitting
for cross feed
Dipstick
Oil level
Oil drain plug
Relief slot
Feed mechanism lead screw
Page 19
AMMCO Drum & Disc Brake Lathes • 15
Cleaning
Keep the lathe as clean as possible for trouble-free
operation, as well as safety and longer lathe life. Use a
brush to sweep metal chips and dust off the lathe.
Do not use compressed air to blow the lathe clean.
Chips and dust may be driven between machined parts
and into bearings, causing undue wear.
Care of Arbors and Adapters
Although the adapters, arbors, and spindle are made
of top grade steel and are turned, hardened, and precision ground to close tolerances, great care should be
taken in their use, handling, and storage. Even the
smallest nick, scratch, or loose chip can cause incorrect
rotor or drum alignment, resulting in inaccurate reconditioning.
Remove all adapters from the arbor after reconditioning a drum or rotor and wipe them clean – especially
the inboard adapter. When a finished drum or rotor is
removed from the arbor, the inboard adapter may
move slightly away from the face of the arbor and allow
metal chips to fall into the opening, causing a poor
mounting for the next drum or rotor.
Regularly inspect the faces and seating tapers of the
adapters for nicks and scratches, correct any flaw with
a fine stone. If the damage cannot be corrected,
replace the adapter. Handle the adapters and arbors
with care and store them on individual hooks. Do not
throw them into a box. The adapters are designed for
mounting drums and rotors only. Do not misuse the
adapters.
Shear Gear Replacement
The shear gear is located in the drive housing under
the dot plug cover. It is designed to “ strip out” and
prevent gearbox damage should a tool accidentally jam.
Remove the dot plug button. Remove the C-clip.
Remove the shear gear. Remove any stripped teeth
from the drive housing. Install the new gear. The concave side of the C-clip faces the gear to maintain pressure. Replace the dot plug button.
Page 20
911005 51 10/12 © Copyright 1992 Hennessy Industries and AMMCO All Rights Reserved Printed in USA
Loading...