Model G9972Z (Mfd. Since 03/20)
-27-
4-Jaw Chuck
The 3-jaw scroll-type chuck has an internal
scroll-gear that moves all jaws in unison when
adjusted with the chuck key. The chuck will hold
cylindrical parts on-center with 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-shaped workpiece. The
chuck will spin out of balance and may throw
the workpiece! Instead, use an independent jaw
chuck or a faceplate.
Insufficient
Jaw Clamping
Unstable
Workpiece
Bar Stock
Cylinder
Unsafe Jaw Position
Poor Scroll
Gear Engagement
Safer Inside
Jaw Use
Unsafe Inside
Jaw Use
Unsafe Jaw
Position
Safer Outside
Jaw Use
Poor Scroll Gear Engagement
Unsafe Jaw Position and
Poor Scroll
Gear
Engagement
Poor Grip
Unstable
Workpiece
Shallow
Bar Stock
Shallow
Bar Stock
Safer Outside
Jaw Use
Safer Inside
Jaw Use
CORRECT
CORRECT
CORRECT
CORRECT
INCORRECT
INCORRECT
INCORRECT
INCORRECT
Scroll Chuck
Clamping
Figure 22. Jaw selection and workpiece holding.
Refer to the
Chuck Installation (see Page 24)
and
Chuck Removal (see Page 25) instructions
to install or remove the 4-jaw chuck.
The 4-jaw chuck features independently adjust-
able hardened steel jaws for holding non-con-
centric or off-center workpieces. Each jaw can
be independently removed from the chuck body
and reversed for a wide range of work holding
versatility.
To mount the workpiece:
1. DISCONNECT LATHE FROM POWER!
2. Place a chuck cradle or plywood on the
bedway below the chuck to protect the
bedway surfaces.
3. Use the chuck key to open each jaw so the
workpiece will lay flat against the chuck face,
jaw steps, or into the spindle opening.
4. With help from another person or a holding
device, position the workpiece so it is cen-
tered in the chuck.
Because of the dynamic forces involved in
machining a non-concentric or off-center
workpiece, always use a low spindle speed
to reduce risk of the workpiece coming
loose and being thrown from the lathe,
which could cause death or serious personal
injury.
Tools Needed:
Qty
4-Jaw Chuck Key .............................................. 1
Dial Indicator ..................................................... 1
Summary of Contents for G9972Z
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