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TRAK Machine Tools
Southwestern Industries, Inc.
TRAK TRL Lathe, ProtoTRAK RLX CNC Safety, Installation, Maintenance, Service & Parts List
4.2 The Mechanical Drive Train (X,Z)
Indications:
Troubleshooting instructions indicate that the drive train is potentially the problem and other, more
easily checked, variables have been exhausted.
Roughness, looseness, tightness or jamming movement in the carriage or cross slide.
Carriage walk-up due to Z ball screw misalignment.
1.
Check for machine considerations, especially X gib adjustments and leveling. See Gib Adjustments,
Section 5.2.1.
2.
The torque required to manual turn the X and Z-axis ballscrews should be between 10 to 15 in-lbs.
These values should be consistent in both directions and along all areas of the axis travel. Values that
differ from that of above may correspond to misaligned ball screws.
The following steps take you in logical sequence through the assemblies. If the step doesn’t isolate or
resolve the problem, it will be necessary to disassemble the indicated item and move to the next step.
See Figures 17 through 22 in Section 5.0. The drawings for the 1845 can be found in the rear of the
manual.
1.
Ensure that the screws that hold the bearing housing in place are not loose.
2.
Ensure that the Clamp Nut is secured. The following applies to the clamp nut: When loosening, make
sure to back out the 10-32 screw from the clamp nut.
3.
When tightening, drag the 10-32 screw to keep the clamp nut from spreading, tighten it again after the
clamp nut is tight. Torque the 10-32 screw to 90 in-lbs. Torque the clamp nut to 50 ft-lbs.
4.
Take out the angular contact bearings in the X & Z-axis and inspect them. They should roll smoothly
and be lightly greased. If not, replace them. The Z-axis has 2 bearing housings. One housing is on the
drive train side with the other on the support housing.
NOTE:
The bearing housing and spacer rings are matched sets - keep them together.
1.
With the motor and drives removed, inspect the ball screw, ball nut and yoke for the potential problems
shown in the chart below.
CAUTION
!
Unlike a leadscrew, do not unscrew the ball screw from its nut. This will destroy the
ball screw!
Potential Problem:
Check By:
Bad ball screw
Visual inspection of the ball nut - if the nylon seal is broken or deformed, if
contamination has visibly entered the ball nut or if balls are out of the ball nut,
replace the ball screw.
Cranking the ball screw through a significant part of its travel. If it jams, feel loose or
has rough spots, replace the ball screw.
Dial indicator on a vertical flat of the ball screw indicates backlash between the ball
screw and ball nut.
Ball nut not
tightened to the
Inspection for space between the head of the bolt and the ball nut i.e. the retaining
bolt has bottomed out in its thread and is not securing the ball nut to the yoke
