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PM 728V-T v2 2020-10
Copyright © 2020 Quality Machine Tools, LLC
The corresponding adjustment for the Y-axis is shown in Fig-
ure 4-4.
Figure 4-4
Y-axis leadscrew nut adjustment
Use a ratcheting wrench with a 4 mm hex insert.
DOWNFEED RETURN SPRING
The quill should automatically retract when the coarse down-
feed levers are released following a drilling operation. If it does
not, check for binding in the quill lock. The return spring, Figure
4-7, is held by a spring cup which is locked to the spindle by
a special C-clip beneath the spindle cap, Figure 4-6. Spring
force is not adjustable.
Figure 4-6
Removing the special C-clip
SERVICING QUILL & SPINDLE
In the normal use the quill assembly needs only oiling on
its sliding surface. The spindle runs on pre-lubricated deep-
groove ball bearings and needs no routine attention. If the
bearings need to be serviced or replaced, remove the quill/
spindle assembly as follows:
IMPORTANT:
Use wood blocks or other means to
protect the
table
, and to prevent
unexpected downward movement
of
the quill assembly.
1. Remove any installed R8 device from the spindle.
2. Lock the spindle with the C-wrench, then unscrew the spin-
dle cap (17 mm flats) from the spindle.
3. Remove the drawbar.
4. Press down on the return spring cup while removing the
C-Clip, Figure 4-6.
5. Remove the return spring, Figure 4-7.
6. Using a 2.5 mm hex key remove the two button head
screws securing the DRO scale and stand-off block to the
quill assembly.
7. Loosen the quill lock lever, then remove the quill assembly
from the headstock.
For access to the leadscrew nut, remove the two screws se-
curing the flange casting at the front. Unscrew the leadscrew,
then slide the saddle/table assembly forward as in Figure 4-5.
Figure 4-5
Withdrawing the Y-axis leadscrew
Return
spring cup
Spindle
cap
Figure 4-7
Quill return spring
