Model G0768/G0769 (Mfd. Since 8/15)
-33-
4. Insert (3) M8-1.25 X 35 set screws through
mounting holes in spindle backplate, as
shown in
Figure 25. Make sure chuck seats
firmly and evenly against backplate shoulder.
This 3-jaw, scroll-type chuck has an internal scroll-
gear that moves all jaws in unison when adjusted
with the chuck key. This chuck holds 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 27. Jaw selection and workpiece holding.
5. Use (1) 8mm flat washer and (1) M8-1.25 hex
nut on each chuck screw to secure chuck
(see
Figure 26). Tighten hex nuts evenly a
small amount at a time and in multiple steps.
Figure 26. Chuck secured against backplate.
Hex Nut
Flat Washer
Figure 25. Inserting chuck into backplate.
Chuck Screw
Spindle
Backplate