Bob Erickson at IBM Almaden's machine shop repaired the
corroded "bad" 1402 actuators (in under 10 minutes).
He used a folded piece of 400 sand paper (a fresh piece per actuator),
wiping back and forth between the contacts as the two arms were
squeezed together. Resistance dropped from >30 Megohms
down to ~0.2 ohms.
One of the actuators had to be disassembled as the problem
was not the contacts, but the stacked spring steel shims
were corroded--showing about 8 ohms before sanding.
(Odd this problem was just in one of the actuators.)
- Robert
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