Southbend SB1224 User Manual

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MODEL SB1224

12" 3-JAWSCROLL CHUCK

Instruction Sheet

PHONE: (360) 734-1540www.southbendlathe.com

Introduction

This chuck uses a direct-mountcamlock system to attach to the spindle.Direct-mountchucks provide a number of advantages over chucks that require a back plate for mounting.

The main benefit is a larger maximum working area between the chuck jaws and tailstock. The increased space is created by the absence of a back plate between the chuck and spindle.

Another benefit is that direct-mountchucks require less initial setup time because the machinist is not required to machine a back plate to fit the chuck.

Reversible Top Jaws

Two-PieceJaws

Two-Piece

 

 

Center

 

 

Split

 

 

Chuck

 

 

Camlock

Rear

Direct

Studs

Mount

 

Chuck Cap

 

Back

 

Screws

 

 

 

 

Threaded

 

 

Pinion

 

 

Retaining

 

 

Pins

Figure 1. Main features of this chuck.

Incorrect use of this tool can result in death or serious injury. For your own safety, read and understand this entire document before using.

Specifications

Mounting Type..........

Direct Mount D1-8Camlock

Chuck Outer Diameter

....................12.2" (310mm)

Chuck Bore Diameter......................

4.05" (103mm)

OD Clamping Range.......

 

0.12"–4.65"(15–300mm)

ID Clamping Range........

 

1.78"–4.61"(90–290mm)

Static Clamping Force...............................

 

9890 lbs

Maximum Chuck Key Torque..................

137 ft/lbs

*Maximum Speed..................................

 

 

1800 RPM

Chuck Jaw M12 Cap Screw Torque........

78.8 ft/lbs

Rear Chuck M12 Cap Screw Torque.......

78.8 ft/lbs

Chuck Weight..............................................

 

 

105 lbs

Country of Origin........................................

 

 

Taiwan

*Even if a tailstock and steady rest are used, the maximum speed rating may not be SAFELY reached with certain workpieces. The workpiece must be balanced and appropriately sized for the chuck and lathe, and the chuck must be properly maintained to achieve maximum clamping force. As spindle speeds increase, centrifugal force also increases. If centrifugal force becomes too great, the workpiece can be thrown from the chuck with deadly force. Always use good judgment with each setup!

Copyright © April, 2011 by South Bend Lathe Co.

WARNING: No portion of this manual may be reproduced without written approval. #CR13937 Printed in Taiwan

Model SB1224

I N S T R U C T I O N S

Mfg. Since 1/11

Chuck Safety

Trained Operators Only. Using a chuck incorrectly can result in workpieces coming loose at high speeds and striking the operator or bystanders with deadly force. To reduce the risk of this hazard, read and understand this document and seek additional training from an experienced chuck user before using this chuck.

Using Correct Equipment. Many workpieces can only be safely turned in a lathe if additional support equipment, such as a tailstock or steady rest, is used. If the operation is too hazardous to be completed with the lathe or existing equipment, the operator must have enough experience to know when to use a different machine or find a safer way.

Disconnect Power. Serious entanglement or impact injuries could occur if the lathe is started while you are adjusting, servicing, or installing the chuck. Always disconnect the lathe from power before performing these procedures.

Handling Chucks. Chucks are heavy and awkward to hold, especially if they are oily. A dropped chuck can result in amputation or crushing injuries and equipment damage.

Always use some kind of chuck cradle, protective device, or lifting assistance when installing and removing chucks.

Chuck Key Safety. A chuck key left in the chuck can become a dangerous projectile when the lathe is started. Always remove the chuck key after using it. Develop a habit of not taking your hand off of a chuck key unless it is removed from the chuck.

Proper Maintenance. All chucks must be properly maintained and lubricated to achieve maximum clamping force and withstand the rigors of centrifugal force. To reduce the risk of a thrown workpiece, follow all maintenance intervals and instructions in this document.

Speed Rates. Fast spindle speeds increase the centrifugal force on the chuck and workpiece. Excessive centrifugal force can cause the chuck to lose its grip and throw a workpiece, or cause a chuck to break apart with deadly consequences. Use slow spindle speeds when ever possible, take all safety precautions, and double check the workpiece for proper clamping and support before starting the lathe.

Chuck Capacity. Avoid exceeding the capacity of the chuck by clamping an oversized workpiece. If the workpiece is too large to safely clamp with the chuck, use a faceplate or a larger chuck if possible. Otherwise, the workpiece could

be thrown from the lathe during operation, resulting in serious impact injury or death.

Clamping Force. Inadequate clamping force can lead to the workpiece being thrown from the chuck and striking the operator or bystanders. Maximum clamping force is achieved when the chuck is properly maintained and lubricated, all jaws are fully engaged with the workpiece, and the maximum chuck clamping diameter is not exceeded.

Entanglement. Entanglement with a rotating chuck can lead to death, amputation, broken bones, or other serious injury. Never attempt to slow or stop the lathe chuck by hand, and always roll up long sleeves, tie back long hair, and remove any jewelry or loose apparel BEFORE operating.

Long Stock. Long stock can suddenly whip violently when the lathe is started, or without warning during lathe operations causing death or serious impact injury. Always use additional support with any workpiece that extends from the chuck or the end of the outboard spindle more than three times the workpiece diameter.

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Mfg. Since 1/11

I N S T R U C T I O N S

Model SB1224

Camlock Stud Installation

This section provides information about how to install and adjust the camlock studs so the chuck properly mounts to the spindle.

Note: You can skip this section if the camlock studs are already installed.

To install the camlock studs:

1.Lightly oil the threads of each stud.

2.Thread the studs into the chuck until the datum line is flush with or just above the surface of the chuck, and the alignment groove is positioned over the hole.

Chuck Installation &

Removal Devices

A dropped chuck can cause amputation, serious crushing injuries, or property damage. Always use a lifting, support, or protective device to reduce this risk when installing or removing a chuck.

Because chucks are heavy and often awkward to hold, some kind of lifting, support, or protective device should be used during installation or removal. The weight and size of the chuck will determine the appropriate device to use (refer to the following figure for examples).

Alignment

Datum Line

Groove

Flush with Chuck

Cap

Surface

 

Screw

 

Figure 2. Camlock stud installation.

3.Install a cap screw in the hole next to each stud. These cap screws prevent the studs from rotating so they properly engage with the camlock during installation.

Note: It is normal for studs to have a small amount of play or looseness after installing and tightening the cap screws.

SMALL, LIGHTWEIGHT CHUCKS

Plywood Protection

 

Plate for Chucks

 

Installed by Hand

 

MEDIUM-SIZE,HEAVY CHUCKS

Plywood & 2x4

Solid Block

Chuck Cradle

Chuck Cradle

 

Way Slot

 

Jaw Slot

Plywood Chuck Cradle

Plywood Chuck Cradle

(Straight Cuts)

(Curved Cuts)

LARGE, VERY HEAVY CHUCKS

Pre-ThreadedHole

Fabricated Steel

for Lifting Eye

Lifting Hook

 

Figure 3. Examples of common devices used during chuck installation and removal.

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Model SB1224

I N S T R U C T I O N S

Mfg. Since 1/11

Chuck Installation

To ensure accurate work, it is extremely important to make sure the spindle nose and chuck mating surfaces/tapers are clean. Even a small amount of lint or debris can affect accuracy.

The chuck is properly installed when all camlocks are tight, the spindle and chuck tapers firmly lock together, and the back of chuck is firmly seated against the face of the spindle all the way around—withoutany gaps.

To install the chuck:

1.DISCONNECT LATHE FROM POWER!

2.Use an appropriate lifting, support, or protective device to protect the ways and support the chuck.

3.Clean and lightly oil the camlock studs, then thoroughly clean the mating surfaces of the spindle and chuck.

4.Install the chuck by inserting the camlock studs straight into the spindle cam holes.

Important: Avoid inserting the studs by pivoting them in from an angle or rotating the spindle. This can damage studs or bores.

CORRECT

INCORRECT

Figure 4. Inserting camlock studs into spindle bores.

5.Incrementally tighten the camlocks in a criss-crossor star pattern to ensure that the chuck seats evenly against the spindle.

6.When the chuck is fully seated and all the camlocks are tight, verify that the cam line is between the two "V" marks on the spindle nose, as shown in the following figure.

Camlock between “V”s

Figure 5. Cam line positioned between the "V" marks after the camlocks are fully tightened.

If the cam line is NOT between the "V" marks when the camlock is tight, the stud may be installed at the incorrect height. To fix this, adjust the stud height as shown in the following figure. Make sure to re-installthe stud cap screw afterward.

If adjusting stud height does not correct the problem, try swapping stud positions on the chuck.

INCORRECT INCORRECT

Stud Too Low:

Turn Out

One-Turn

Figure 6. Correcting an improperly installed stud.

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Mfg. Since 1/11

I N S T R U C T I O N S

Model SB1224

7.Verify that the chuck fits the spindle properly by checking for any gaps between the mating surfaces.

If there are no gaps, proceed to Step 9.

If there is a gap, remove the chuck, reclean the mating surfaces carefully, and re-install.If the problem persists, refer to

Troubleshooting.

8.Verify that the chuck/spindle tapers are seating firmly together by removing the chuck, per the Chuck Removal

instructions, and paying close attention to how easily the tapers release.

If it was necessary to bump the chuck or use a mallet to release the tapers, then they are seating together properly.

If the tapers released easily with little intervention, they are not seating together firmly as required. Remove the chuck, reclean the mating surfaces carefully, and re-install.If the problem persists, refer to

Troubleshooting.

Registration Marks

Lightly stamp registration marks across the mating seams of chuck components. These marks will help you re-installthe chuck in the same position after removal, which ensures consistent chuck balance and turning results, and allows the same camlocks and studs to operate together for consistent locking and unlocking.

Camlock

Spindle & Chuck

Registration Marks

Spindle

Chuck

 

 

Halves

Marks

2-Piece

for Chuck

Direct Mount

Reassembly

Camlock Chuck

 

Figure 7. Registration mark locations.

Chuck Removal

To remove the chuck:

1.DISCONNECT LATHE FROM POWER!

2.Use an appropriate lifting, support, or protective device to protect the ways and support the chuck.

3.Loosen the camlocks by turning the key counterclockwise until the cam lines are aligned with the mark on the spindle nose.

Tip: Camlocks can become very tight. A cheater pipe may be used as a last resort to add leverage when loosening. After loosening, you may need to wiggle the chuck key in the camlock to fully disengage the stud.

Cam line aligned with spindle mark

Figure 8. Camlock is fully loosened when the cam line is aligned with the spindle mark.

4.Using a dead blow hammer or other soft mallet, lightly tap around the outer

circumference of the chuck body to loosen it from the spindle.

5.Remove the chuck from the spindle, using a light rocking motion to carefully slide the studs out of the bores.

If the chuck does not immediately come off, rotate it approximately 60˚ and tap it again. Make sure all the marks on the

cams and spindle are in proper alignment for removal.

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Model SB1224

I N S T R U C T I O N S

Mfg. Since 1/11

Scroll Chuck Clamping

This scroll-typechuck has an internalscroll-gearthat moves all jaws in unison when adjusted with the chuck key. This chuck will hold cylindrical partson-centerwith the axis of spindle rotation and can be rotated at high speeds if the workpiece is properly clamped and balanced.

Never mix jaw types or positions to accommodate an odd-shapedworkpiece.

The chuck will spin out of balance and may throw the workpiece! Instead, use an independent jaw chuck or a faceplate.

Safer Inside

Insufficient

Jaw Use

Jaw Clamping

Bar Stock

 

 

Unstable

 

Workpiece

Safer Outside

Unsafe Jaw Position and

Poor Scroll Gear Engagement

Jaw Use

Poor

Shallow

Grip

Bar Stock

Unstable

 

 

Workpiece

Safer Outside

Unsafe Inside

Jaw Use

Jaw Use

Shallow

 

Bar Stock

 

Unsafe Jaw Position and

Poor Scroll Gear Engagement

Safer Inside

Unsafe Jaw Position

Jaw Use

 

Cylinder

Poor Scroll

Gear Engagement

Figure 9. Jaw selection and workpiece holding.

Chuck Jaw Reversal

This chuck has 2-piecejaws that consist of a top jaw and a master jaw. The top jaw can be removed, rotated 180°, andre-installedin the reverse position for additionalwork-holdingoptions. When reversing the top jaws, always keep them matched with their original master jaw to ensure the best fit.

To reverse 2-piecejaws:

1.DISCONNECT MACHINE FROM POWER!

2.Remove the cap screws that secure the top jaw to the master (bottom) jaw.

3.Remove the top jaw, rotate it 180°, then reinstall it with the longest cap screw in the tallest portion of the jaw.

4.Repeat Steps 2–3 with each remaining jaw (we recommend only reversing one jaw at a time to keep all original parts together).

Short Cap Screw

Long Cap Screw

 

Rotate Top

 

Jaw 180º

Master

 

Jaw

 

Figure 10. Reversing the chuck jaws.

Remove all tools before turning lathe ON. Thrown tools can cause serious injury or death to operator or bystanders.

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Mfg. Since 1/11

I N S T R U C T I O N S

Model SB1224

Maintenance

A chuck can only achieve its maximum clamping force when its internal components are clean and well lubricated.

During operation, centrifugal force displaces and thins the lubricant inside the chuck, forcing it out over time. If the chuck is exposed to cutting fluid, this process happens even faster. If maintenance is not followed daily, the chuck will lose its internal lubrication and collect cutting fluid sludge, rust, and metal chips—whichcan cut the maximum chuck clamping force in half!

A chuck with reduced clamping force has a much higher risk of losing its grip during operation and throwing the workpiece with deadly force.

Daily Maintenance

Check/correct loose mounting bolts.

Use a vacuum, rag, or brush to clean the chuck after use.

Wipe down the outside of the chuck with a light machine oil or way oil.

Regular Lubrication

Recommended Lubricant

Chuck Grease

.............................. Bison #7-799-025

(or Equiv. Moly-DisulphideChuck Grease)

Oil .........................

South Bend Way Oil #SB1365

Lubricate the scroll thread and jaw slides regularly, using either chuck grease or way oil. To lubricate, remove and clean the jaws, clean chips off the scroll gear if necessary, then reinstall the jaws and apply lubricant to the scroll gear and jaw sliding surfaces. Move the jaws in and out to distribute the lubricant.

Chuck grease provides superior lubrication and clamping force; its drawback is that chips easily stick to it and get drawn into the chuck, leading to binding and reduced clamping force.

Way oil is a good alternative lubricant to reduce the amount of chips that stick to the chuck;

its drawback is a reduction of clamping force, making it a poor choice for heavy clamping loads.

Chuck Service

Proper chuck service requires full disassembly, cleaning, and lubrication. Perform this service every six months, or more frequently if the chuck is exposed to dirty work environments, heavy workloads, or cutting fluid.

To avoid damage when servicing the chuck:

Only clamp chuck parts in a vise equipped with soft jaws or wood/aluminum blocks.

Never use an open flame on chuck parts!

Never strike the chuck with a steel hammer. Instead use a brass hammer or soft mallet.

Never apply force to stuck components if you are unsure about how they are fastened together. Refer to the instructions.

When separating or removing mated components, do not attempt to pry or wedge them apart. Instead, patiently tap them at various locations with a brass hammer or mallet while rotating and pulling on them.

If the scroll gear or retainer is stuck, soak parts in penetrating oil or solvent (overnight if needed) to break down grease suction, then carefully rotate, lift, and tap it loose.

Items Needed

 

Qty

Hex Wrench Set (Metric).......................................

1

High Resolution Caliper 8"...................................

1

Crocus Cloth & Wire Brush............................

1 Ea

Diamond Hone or Dressing Stones............

Various

Files & Thread Chasing Tools....................

Various

Mineral Spirits and Cotton Rags.......

As Required

Calibrated Torque Wrench ...................................

1

Stiff 1" Brush for Applying Grease.......................

1

Oil .........................

South Bend Way Oil #SB1365

Chuck Grease..............................

Bison #7-799-025

(or Equiv. Moly-DisulphideChuck Grease)

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Model SB1224

I N S T R U C T I O N S

 

Mfg. Since 1/11

Disassembly

Inspection & Dressing

 

1.Verify that registration marks have been Inspect all components carefully for burrs, wear,

made on the chuck and spindle. (Refer to Registration Marks section for details.)

2.Inspect the jaws and their slots to make sure they have matching numbers or marks. If none are found, stamp or scribe your own before continuing. (During re-assembly,jaws must be installed in the same slots.)

3.Use the chuck key to back out and remove the chuck jaws.

4.Unthread all chuck fasteners and separate the chuck halves, then remove the remaining chuck components to completely disassemble the chuck (see below).

scoring, bent parts, cracks, and thread damage.

Carefully inspect the chuck jaw clamping surface for tapered wear from front to back. For minor wear, jaw regrinding may be more economical than jaw replacement. If the taper is heavy,

or grip, or work holding accuracy is a problem, chuck replacement is likely required.

Burrs, dings, flakes, high spots, or galled surfaces can usually be removed by lightly dressing them away with diamond lapping boards or honing stones with lapping oil. Be sure not to change part dimensions while dressing surfaces. Thread damage can usually be corrected with files and thread chasing tools.

Rear

Pinion

Chuck Body

and

and Fasteners

Retaining Pin

Scroll Gear

 

 

Front

 

Chuck Body

Figure 11. Chuck components.

If any parts are overly worn, bent, cracked, or otherwise damaged, they must be replaced (if available). Never attempt to repair chuck

components by welding them. If damaged parts are unavailable, replace the chuck. Continuing to use a chuck with damaged components will increase the risk of accidental death or serious injury. Do not risk it!

If replacing fasteners, make sure to use the same hardness or grade as the original fasteners that were installed on the chuck.

Cleaning

When cleaning chuck components, make sure to remove all grease, sludge, and metal particles using a brush and clear-typemineral spirits

or standard paint thinner. Avoid using whitecolored mineral spirits, acetone, brake parts cleaner, gasoline, or acids. If an incorrect solvent is used, stains, additives, acids, or contaminants can be left behind as a corrosive coating. After cleaning and drying parts, be sure to wipe down parts with an oiled rag to prevent rust.

Light rust can be removed in a blast cabinet with soda blasting media. For heavy rust, have the chuck components “hot tanked” at a local automotive machine shop (remove all non-ferrousitems first or they may dissolve).

Reassembly

Brush all internal chuck components with a generous coat of chuck grease, but do not pack the chuck full of grease. Re-assemblecomponents in the reverse order of disassembly. Make sure to follow theChuck Jaw Installation instructions to ensure that the jaws are installed correctly.

Make sure you only use approved chuck lubricants. Some lubricants can stain your chuck or have unintended reactions with cutting fluid, which will destroy their ability to properly lubricate the chuck.

To avoid stripping threads or cracking a casting, never use fasteners to draw components together and avoid using impact tools. Instead, be patient and properly seat the mating parts, then use hand tools and a recently calibrated torque wrench to tighten fasteners.

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Mfg. Since 1/11

I N S T R U C T I O N S

Model SB1224

Chuck Jaw Installation

When installing the jaws on a scroll chuck, it is important to make sure they are installed correctly. Incorrect installation will result in

jaws that do not converge evenly and are unable to securely clamp a workpiece.

To install chuck jaws:

1.Rotate the chuck key clockwise until you see the tip of the scroll-gearlead thread just begin to enter jaw guide #1.

Lead Thread

(Locations

May Vary)

Figure 12. Installing jaw #1.

2.Insert jaw #1 into jaw guide #1, and hold the jaw against the scroll-gear.

3.Rotate the chuck key clockwise one turn to engage the tip of the scroll-gearlead thread into the jaw. Pull the jaw; it should be locked into the jaw guide.

4.Install the remaining jaws in numerical order, in the same manner.

If installed correctly, the jaws will converge evenly at the center of the chuck.

If the jaws do not converge evenly, remove them. Make sure the numbers of the jaws and jaw guides match, then re-installthe jaws and make sure each one engages with thescroll-gearlead thread during its first rotation.

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Model SB1224 I N S T R U C T I O N S Mfg. Since 1/11

Troubleshooting

Symptom

 

Possible Cause

 

Possible Solution

 

 

 

 

 

The chuck key

1.

Jaws poorly positioned.

1.

Re-installjaws in correct order and position.

is hard to turn,

2.

Lack of lubrication; rust, burrs, metal

2.

Disassemble, de-burr,clean, andre-lubricatechuck

or it binds

 

chips, or contaminants inside chuck.

 

with chuck grease.

at some jaw

 

 

3.

Jaw guides, scroll gear, or pinion

3.

Replace damaged parts, or replace chuck.

locations.

 

 

distorted, worn, or broken.

 

 

 

 

 

 

 

Chuck mounts

1.

Chuck is loose or cocked on spindle; gap

1.

Remove chuck then clean and dress all mating

or seats

 

between spindle/chuck mating.

 

surfaces of spindle & chuck.

incorrectly;

2.

Chuck is too large for lathe.

2.

Install smaller lathe chuck so spindle and bearings

gap exists

 

 

 

will not become overloaded and vibrate.

between chuck

 

 

 

3.

Lathe spindle is loose.

3.

Check and adjust lathe spindle end-playand

and spindle;

 

 

 

bearing preload.

chuck vibrates

 

 

 

 

 

 

 

during

4.

Camlock studs are at fault.

4.

Remove chuck and inspect/adjust/replace camlock

operation

 

 

 

studs for wear or damage as required. Re-install

without a

 

 

 

chuck with registration marks aligned.

workpiece

5.

Lathe spindle is loose.

5.

Check and adjust lathe spindle end-playand

installed.

 

 

 

bearing preload. Adjust as required.

 

 

 

 

 

6 .

Poor chuck/spindle taper fit causes

6 .

Isolate component at fault by installing a different

 

 

radial or axil runout from chuck shifting

 

chuck. If problem persists, lathe spindle may be at

 

 

when camlocks are tightened.

 

fault. If problem goes away, chuck may be at fault.

 

7.

Chuck is distorted or cracked.

7.

Replace chuck.

 

 

 

 

 

 

 

 

 

 

Workpiece

1.

Workpiece is too long for jaw clamping

1.

Use tailstock, rests, and outboard spindle support;

has runout;

 

only.

 

use slower spindle speeds.

clamping

2.

Workpiece is improperly clamped or is

2.

Remove jaws, then clean, de-burr,andre-install.

accuracy or

 

misaligned.

 

 

repeatability is

 

 

 

3.

Jaws are positioned in the wrong jaw

3.

Re-installjaws in their correct guides.

poor; turning

results are

 

guides.

 

 

poor.

4.

Top jaws are loose or improperly seated

4.

Remove jaws, clean jaw teeth and guides, then re-

 

 

in their master jaws.

 

install jaws using the correct torque for fasteners.

 

5.

Chuck is loose; mounting is off center or

5.

Refer to troubleshooting for chuck mounting

 

 

improperly seated.

 

incorrectly.

 

6.

Lathe spindle, tailstock, or cross slide is

6.

Align lathe components.

 

 

misaligned with lathe bed.

 

 

 

7.

Lathe bed is twisted.

7.

Place shims under lathe to level bed ways.

 

 

 

 

 

The workpiece

1.

Workpiece requires additional support

1.

Use tailstock, rests, and outboard spindle support.

slips in the

 

in addition to chuck jaws.

 

Use slower spindle speed.

jaws.

2.

Incorrect jaw or workpiece clamping

2.

Re-positionjaws and workpiece for maximum scroll

 

 

 

position.

 

gear and jaw engagement. Verify that workpiece is

 

 

 

 

not too large or heavy for chuck.

 

3.

Two-piecejaw is loose; top jaw

3.

Remove jaws, clean mounting surfaces, and re-

 

 

improperly seated in master jaw.

 

install with the correct cap screw torque.

 

4.

Insufficient pinion and scroll gear

4.

Lubricate chuck, and re-tightenthe chuck key.

 

 

torque.

 

 

 

5.

Jaws or jaw screws bind before full

5.

Service the chuck as described in this document.

 

 

clamping force is achieved.

 

 

 

6.

Cutting overload.

6.

Reduce cutting depth or feed rate.

 

7.

Jaw teeth worn; 2-piecejaw is loose.

7.

Have jaws reground, replace jaws, or replace chuck.

 

 

 

 

 

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