Jet JTM-1050VS2, Operating Instructions And Parts Manual

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11.3.3 Table gib
Adjust gib between table and saddle by turning two
adjustment screws (C, Figure 11-3) at left and right
of saddle. Use dial indicator to measure amount of
movement in table. Adjust gib until indicator
reading is within 0.003”.
Figure 11-3: Gib locations
11.3.4 Ram gib
Adjust ram gib (E, Figure 11-4) by turning the two
set screws (F).
Figure 11-4: Ram gib location
11.4 Leadscrew backlash adjustment
The milling machine table is moved by a leadscrew
and nut for each machine axis. For proper
operation, there must be clearance between
leadscrew and nut, which may result in backlash. A
second feed screw nut is provided to eliminate
most of the backlash. The following procedures
provide instructions for obtaining acceptable
backlash.
11.4.1 Cross feed backlash
Refer to Figure 11-9.
1. Use cross feed crank to move table to extreme
rear of its travel (toward column).
2. Remove pleated way cover.
3. Open chip guards (#51-53, sect. 13.3.1)
enough to expose cross feed adjustment nut
(the nut toward rear of feed nut bracket is not
adjustable; only front nut is adjustable).
4. Loosen the two nut locking screws.
5. Turn nut slightly to tighten it against opposing
nut.
6. Tighten the two nut locking screws.
7. Using cross-feed crank, move table to middle
position.
8. Set up a dial indicator to check cross feed
backlash. Gently move cross feed crank back
and forth while watching dial indicator.
Backlash should be between 0.003 inch and
0.005 inch.
9. If necessary, repeat the above steps to set
backlash.
10. Install pleated way cover.
11.4.2 Longitudinal backlash
Refer to Figure 11-9.
1. Only one of the longitudinal leadscrew nuts
can be adjusted; the other nut is fixed. The left
hand nut is typically adjustable. This can be
determined by looking at nut from underside of
table.
2. Loosen the two nut locking screws.
3. Turn the nut slightly to tighten it against the
opposing nut.
4. Tighten the two nut locking screws.
5. Using one of the longitudinal table cranks,
move table to middle position.
6. Set up a dial indicator to check longitudinal
backlash. Gently move crank back and forth
while watching dial indicator. The backlash
should be between 0.003 inch and 0.005 inch.
7. If necessary, repeat the above steps to set
backlash.