Drive Disk and Rollers

Remove Nose Cover Panel, D8810 item 3, then remove cladding panel, D8802-1.

Remove cladding panel, D8796-1.

Check Instrument balance before proceeding. Balance should be within 0.5 amp. If it is out of balance, clamp a weight onto cladding to simulate removed sections.

Clean and inspect.

Remove wipers, D6392, inspect for contaminates, and clean.

Clean friction surfaces of drive disk and rollers with solvent on a rag.

Re-install wipers.

Inspect patch and skew.

Run a piece of green engineering paper between drive disk and drive roller while rotating DEIMOS. Run other edge of same piece between drive disk and idler roller.

Measure thickness of paper on either side of each track with a micrometer. Thickness of two sides should not differ by more than 0.0002”.

Mount a dial indicator on a surface gauge. Hold against drive disk and sweep across drive roller face, through the center of the face, in an arc parallel to edge of drive disk. Do same for idler roller. Variation from one side of roller to the other should not exceed  0.002”.

Adjusting patch and skew is done per D6110 for the large rollers and D6115 for the small rollers. Note: the large roller adjustments are not determinate. The ¾-16 hex screws, D6110 item 35, hold the primary load for patch and skew. The Carr-Lane Foot, D6110 item 8, act primarily to hold the spherical bearing, D6110 item 6, together, but they also hold part of the patch and skew load.  Adjusting one affects the other.