Jet JTM-1050, Operating Instructions And Parts Manual

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3. Lower quill to fullest extent.
4. Remove two lower screws from variable speed
housing (A, Figure 21).
5. Remove six screws (B).
6. Remove top assembly (C) and tap to clear
dowels.
7. Replace timing belt.
8. Reverse procedure to reassemble.
Figure 20: Timing belt replacement
13.6 Drive belt replacement
Refer to Figure 21.
1. Disconnect machine from power source.
2. Remove motor.
3. Remove three screws (A, Figure 21). Thread
the screws into the adjacent tapped holes and
back off the cover (B).
Figure 21: Drive belt replacement
4. Remove two screws and bushings (C) from
tilting plate.
5. Remove four screws (D) and one screw (E).
6. Remove four screws from variable speed
housing (F).
7. Remove top housing (G) and tap to clear
dowels.
8. Replace belt.
13.7 Brake shoe replacement
Refer to Figure 22 .
1. Disconnect machine from power source.
2. Remove top section.
3. Remove two screws (A, Figure 22).
4. Remove clutch hub assembly (B/D).
5. Replace brake shoes (C).
Figure 22: Brake shoe replacement
13.8 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 results in backlash. A
second feed screw nut is provided to eliminate
most of the backlash. The following procedures
provide instructions for obtaining acceptable
backlash.
13.8.1 Cross feed backlash
Refer to Figure 23.
1. Use cross feed crank to move table to extreme
rear of its travel (toward column).
2. Remove pleated way cover.
3. Open the two chip guards (#61/62, sect.
14.3.1) 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.