Tony Duell wrote:
I wonder why
the squeal happens? Whether it's wear on the spring side or the
spindle side? If the former, then a donor spring
from a scrap unit could fix
things.
I would be suprised if the spindle wears, they're normally pretty hard.
Often the spring was a replaceable part in the boardswapper guide for the
drives, and I think replacing it might well cure the noise.
One fix, "back in the day" was to glue a piece of blue teflon material
onto the backside of the spring. I'm not an ME but I'm guessing this
changed the natural freq at which it would oscillate.
I don't know what the material was (other than "teflon"), but I seem to
recall at least one mfg did this. some of those memories are a bit dim :-)
-brad