Lubing Shugart 800,801's?

From: allisonp_at_world.std.com <(allisonp_at_world.std.com)>
Date: Fri Apr 14 13:51:00 2000

> Though you may be able to "feel" your way around, maybe with a 'scope to
> check signal amplitude, I rather doubt you'll be able to eyeball in the
> index alignment, which I've found to be far and away the most common
> misalignment. The spec for that is referenced to the index pulse, and the
> timing is nominally 200 uSEC give or take 100. That doesn't sound bad, but
> since you can't see the reference, and have no calibrated reference without
> an alignment diskette, I doubt you can do it using "the force".
>
> If you remove the stepper/lead-screw-head-assembly unit, you have to set the
> azimuthal alignment as well, and that one is quite easily mucked up. Drives
> are not very tolerant of this one and a 1-2-degree misadjustment can cause
> quite a lot of error.


RE: OK.

I've done it. if everything was close or correct to startwith and the only
problem is lube then it's liitle trouble to put widows marks and
disassemble the leadscrew clean and assemble to origional positions or
very nearly so. Doing that should not affect index as that is sensor to
spindle, wich is not touched. Track 00 also no need to remove. Asmuth
as function of the head and also not disassembled so no new problems
there.

Alignment on eyeball was done on cut/try and successful enough to get by.
With a scope an eye pattern setup and several disks will do better.
All I've done over 20+ years were tested once operational with dysan test
disk and only needed a minor tweek. Why test on live then using dysan
disk...? once it's working you can be sure you not going to foul the only
test disk!

Allison
Received on Fri Apr 14 2000 - 13:51:00 BST