[rescue] SA4008 disk drive belt?

[Carl R. Friend]

    On Sat, 24 Jan 2009, Skeezics Boondoggle wrote:

> [...] Or suggestions for how to safely refurbish one?

    Refurb'ing a belt, I suspect, is nigh-well impossible; you'll
likely need to locate some NOS or "find" something that works.

> It's physically in good shape, with no apparent cracks, warping or
> damage, but it slips off just a few seconds after applying power.

    Those drives, if I recall correctly, use slightly convex pulleys;
you might try putting the belt on "upside down" to see if it comes
off in the "other direction".  If it does, it's likely because the
belt is slightly stretched more along one edge than the other, and
that's causing it it "guide off center" to the point where it comes
off altogether.  Also, make really sure that the pulleys themselves
are clean with no residue of any kind on them.

> The inside of the belt has pretty much worn smooth.  There are no
> instructions in the OEM manual or readily apparent tensioning
> adjustments on the drive.

    Just because the inner surface of the belt is smooth to the
touch is not necessarily an indication that it's kaput; it's the
"derailing" behaviour that's key.  Too, and this is from menmory,
the belts were ever-so-slightly stretchy, so tensioning arrangements
might well not have been part of the design.  You should also make
very sure that both the motor and the spindle are securely mounted
to the frame and that there's not a lot of play in either's bearings.

    Good luck with it!

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| Carl Richard Friend (UNIX Sysadmin)            | West Boylston       |
| Minicomputer Collector / Enthusiast            | Massachusetts, USA  |
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