> >> try giving it a solid tap with the handle of a screwdriver on the side
> >> of the disk just as it makes the rubbing noise.  I've also found a one
> >> inch drop of a corner can help.
> >
> > What if it does start spinning? I didn't do this (tapping), because I 
> > believe jerking an old drive  while the platter is moving may really crash the
> > heads (am I wrong?)
> 
> If it does start spinning by itself then the drives doesn't have stiction
> and I wouldn't hit it.
> 
> Stiction is often caused by the spindle lubricant locking up when the drive
> cools down, and can be worked around by bumping the drive while the motor
> is trying to turn.  On small 3.5" drives I have sometimes fixed it by
> picking up the drive and giving it a sharp twist around the axis of the
> spindle.  Obviously it is a bit harder to do this with a drive the size
> of the RZ55...
> By the way, if a drive has to be started this way, the next thing to do
> is back it up ASAP and then get rid of it.  Once a drive has stiction it
> basically means the lubricant is stuffed.
> 
> If the drive spins up but still doesn't work, the only other things I can
> think of are double-checking your cabling (power and SCSI - including
> termination) and the drive's jumpers to see if anything's changed.
> However, the symptom of "a rubbing noise" makes me think that the fix will
> be to drop the drive - into a bin :(

	I might have something to add.  I've not used an RZ55 myself, but
I did have the experience of working on a dying RZ57.  About half the
time it wouldn't spin up, and the other half it would start to spin up
and then the motor would kick out and it would go back to rest.

	We tried dropping it a couple of times (about 6"), which
didn't help.  We also tried some of the twist movements, no go.
Finally in a last ditch of hope we got the logic board of another
RZ57 and swapped it in, and viola, the drive worked.  It appears
there was some voltage regulation or something on the logic board
keeping the thing from working.

	Another thing I have seen people do to drives that won't spin
up is to overdrive them, ie give them +7 rather than +5 volts or so.
As you might guess, this is very hard on a drive's electronics, and
should only be done long enough to copy everything off the drive.
I'm not sure I would recomend it, but if your desperate.....

	All drive damage is entirely the responsibility of the owner. :-)
-- 
Leo Bicknell - TMBG List Admin - tmbg-list-request@tmbg.org
         System Administrator / Network Technician
  bicknell@ufp.org - bicknell@vt.edu - bicknell@tmbg.org