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2.
Lock the X-axis by tightening both levers, Figure 3-4
().
3.
If the reference edge is already to the back the spindle
centerline, do nothing; if not, rotate the Y-axis hand-
wheel clockwise to send the workpiece backwards
(toward the column).
4.
Engage the fine downfeed, Figure 3-8.
5.
With the spindle running, lower the quill as neces-
sary using the fine downfeed handwheel; bring the
table forward (counter-clockwise), stopping at the
point where the edge-finder just makes contact (the
tip jumps out of line). Stop the spindle.
6.
While holding the Y-axis handwheel to prevent move-
ment, zero the dial, then re-tighten the dial thumb-
screw, Figure 3-4 (2).
7.
Raise the quill, then rotate the handwheel one exact
full turn counter-clockwise (0.") to bring the refer-
ence edge to the spindle centerline.
8.
Rotate the handwheel 2-/2 turns counter-clockwise
to bring 50 on the dial opposite the datum; the spindle
is now exactly 0.25" behind the reference edge.
Be sure to loosen the X-axis locking levers be-
fore moving the table, especially under power.
DRO
The DRO is in metric mode when switched on. Press the
mm/in button to display inches. By pressing and holding
the Up arrow (incrementing) or Down arrow (decrement-
ing) the display can be set to a chosen value. The longer
the buttons are held down, the faster the change in dis-
played value. Zero the display at any time by pressing
the ON/O button.
Switch off the DRO when not in use!
Replace the battery by sliding the cover (small arrow) to
the right. For longer battery life use a .5V silver oxide
battery, SR44 or equivalent.
QUILL DOWNFEED
Mills without power downfeed
The quill is controlled in two different ways, coarse and
fine.
In the drilling mode, coarse feed, the mill functions like
a standard drill press – lower the quill using any of the
three downfeed levers to rotate the lever hub counter-
clockwise. For milling operations the lever hub is disen-
gaged, and the quill is controlled by the fine downfeed
handwheel. The quill is locked by a lever at lower right of
PM-940M 0-206 v.indd
the headstock front panel, Figure 3-9.
Figure 3-8 Quill downfeed controls
The lever hub (1) is full-time connected to the quill pinion. The
fine control handwheel (2) is connected by a worm gear to the
sleeve (3), and is free to rotate — doing nothing to the quill
— unless it is coupled to the lever hub (1). Couple sleeve (3)
to hub (1) by tightening knob (4).
Coarse feed (Figure 3-8)
For drilling operations, loosen knob (4), allowing the le-
ver hub to rotate independently of sleeve (3). If desired,
set the depth stop, Figure 3-9.
Fine feed (Figure 3-8)
For milling operations calling for precise, repeatable
control of tool depth, tighten knob (4) to engage the ta-
pered face of hub () with the internal taper on sleeve
(3). Tighten the Z-axis locks, Figure 3-4.
Rotate the fine control handwheel (2) to raise or lower
the quill. Before switching to fine control, it is usually a
good idea to run the depth stop up to the top. Lower the
quill by rotating the fine control knob clockwise, position-
ing it precisely either by counting divisions on the gradu-
ated dial, or by reference to the front panel DRO (digital
readout). Use the locking lever to hold the quill firmly in
position.
If you are counting divisions be aware of backlash in the
worm drive. This means that the handwheel must always
be turning in the same direction throughout the entire
process, from setting a reference level to subsequent
cutting passes at specific depths – see the backlash dis-
cussion in "Moving the table", above. Using the DRO
4
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