Fine Downfeed - Grizzly G0827 Owner's Manual

Fine Downfeed

When the fine downfeed is engaged, the spindle
only moves up or down when the handwheel
(see Figure 51) is rotated (there is no automatic
spindle return to the top position, as with the
coarse downfeed controls). This level of control
allows the spindle height to be locked in place
with the quill lock when milling a flat surface
across the face of a workpiece.
Note: The graduated dial on the fine downfeed
handle measures spindle movement in 0.001"
increments, with one full revolution equaling 0.100"
of spindle travel. The dial has a thumbscrew that
is used to adjust the dial to "0".
Fine
Downfeed
Handwheel
Quill
Lock
Figure 51. Fine downfeed controls.
Model G0827 (Mfd. Since 11/17)
Selection
Lever
Thumbscrew
Using Fine Downfeed Controls
In the following example, the fine downfeed
controls are used to mill 0.010" off a workpiece:
1.
Use Z-axis crank to adjust workpiece surface
just below cutting tool, then secure the head-
stock with Z-axis lock lever.
2. Tighten selection lever (see Figure 51) to
engage fine downfeed handwheel.
3.
Loosen quill lock.
4.
Rotate fine downfeed handwheel clockwise
and lower cutting tool so it just touches
workpiece.
5. Move workpiece out of the way.
6. Using graduated dial to gauge spindle move-
ment, rotate fine downfeed handwheel clock-
wise 0.010".
7. Tighten quill lock.
8. Turn mill ON and perform cutting pass.
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