Gatan 656, Руководство пользователя, Страница: 36 / 49

Performance Check
26 Dimple Grinder User’s Guide
Minor damage to the axle male taper can be repaired by turning on the
motor at full speed, placing a minute quantity of diamond compound into
the female taper of a wheel and carefully lapping the two. Do not permit the
diamond compound to go beyond the wheel edge.
• If excessive run-out persists, the axle assembly must be replaced.
5.4 Vertical Movement of the Specimen Turntable
Excessive vertical movement of the specimen turntable causes similar problems
to excessive run-out of the grinding wheel axis.
To check for turntable vertical movement
1. Remove any wheel that may be mounted to the axle.
Carefully clean the axle surface with a tissue.
Caution
:
Do not flood the axle with solvent, as this may wash grit into the axle
bearings.
2. Place a stainless steel specimen mount into the centering ring and place
both on the Magnetic Table.
Use the cross hair of the microscope to center the post.
3. Set a Counterweight load of 20 g.
4. Switch off the wheel motor; turn on the turntable motor
5. Carefully lower the Platform.
6. The reading on the Dial Indicator must change by no more than 2 µm
total (TIR).
If the reading is greater than this value, you can:
• Check that the turntable surface and specimen mounts are clean.
• If the cause of the vertical movement cannot be identified, the complete
turntable assembly must be replaced.
5.5 Grinding Wheel Alignment
As discussed in Section 3.4, the contact point of the grinding wheel must be on
the rotational axis of the Magnetic Turntable. This configuration is more critical
for spherical-edged wheels than for flat-edged wheels.