>> 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 :(

- David B.
  davidb@telstra.com.au

P.S.
	Sorry for jumping in, Simon - I happened to be awake and logged in...