Southbend SB1224 User Manual

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* 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!

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

This chuck uses a direct-mount camlock system
to attach to the spindle. Direct-mount chucks
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-mount chucks
require less initial setup time because the
machinist is not required to machine a back plate
to fit the chuck.

Introduction

Reversible Top Jaws

Two-Piece

Center

Split

Chuck

MODEL SB1224

12" 3-JAW SCROLL CHUCK

Instruction Sheet

Specifications

Mounting Type ......... Direct Mount D1-8 Camlock

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)

Two-Piece Jaws

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

Camlock

Studs

Figure 1. Main features of this chuck.

WARNING: No portion of this manual may be reproduced without written approval.

Rear

Chuck Cap

Screws

Threaded

Retaining

Copyright © April, 2011 by South Bend Lathe Co.

#CR13937 Printed in Taiwan

Direct

Mount

Back

Pinion

Pins

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.

Model SB1224

Chuck Safety

INSTRUCTIONS

Mfg. Since 1/11

-2-

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).

Pre-Threaded Hole
for Lifting Eye

Way Slot

Jaw Slot

Plywood & 2x4
Chuck Cradle

Plywood Chuck Cradle
(Straight Cuts)

Plywood Chuck Cradle
(Curved Cuts)

Fabricated Steel
Lifting Hook

Solid Block
Chuck Cradle

Plywood Protection
Plate for Chucks
Installed by Hand

SMALL, LIGHTWEIGHT CHUCKS

MEDIUM-SIZE, HEAVY CHUCKS

LARGE, VERY HEAVY CHUCKS

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.

Cap

Screw

Datum Line

Flush with Chuck

Surface

Alignment

Groove

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.

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.

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.

Mfg. Since 1/11 Model SB1224

INSTRUCTIONS

Camlock Stud
Installation

Chuck Installation &
Removal Devices

Figure 2. Camlock stud installation.

Figure 3. Examples of common devices used during

chuck installation and removal.

-3-

INCORRECTCORRECT

5. Incrementally tighten the camlocks in a

criss-cross or 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.

— 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-install the stud cap screw afterward.

— If adjusting stud height does not correct

the problem, try swapping stud positions
on the chuck.

Camlock between “V”s

Stud Too High:

Turn In

One-Turn

Stud Too Low:

Turn Out
One-Turn

INCORRECT INCORRECT

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.

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—without any gaps.

Model SB1224

INSTRUCTIONS

Chuck Installation

Mfg. Since 1/11

Figure 5. Cam line positioned between the "V" marks

after the camlocks are fully tightened.

Figure 4. Inserting camlock studs into spindle bores.

-4-

Figure 6. Correcting an improperly installed stud.