I vaguely remember the "sticktion" problem.  This occurred when the drive
would be powered down for some reason and then would refuse to spin up when
power was applied to it again.  I think or CE's were saying there was some
kind of grommet that deteriorated over time and just stuck to the spindle
shaft when the drive was powered down and it colled a bit.

At about that time the Eagle disk drive started appearing and this actually
caused me some worry.  Up to that point, all the disk drives I had used had
removable packs (one way or the other of the 7933, we knew how to do it.)
The vast majority of problems with the disk drives were power and head
related.  If you had a disk drive break down on you, you could remove the
pack and put it into a spare drive and get production going.

With the Eagle drive, this option was no longer viable; if the drive packed
it in, it was reload time.  This was a bit of a change and it took some
getting used to.  It seems a little funny, 20 years later.

Denys...

-----Original Message-----
From: Steve Gray [mailto:[log in to unmask]] 
Sent: Thursday, March 06, 2008 11:45 PM
To: Denys Beauchemin; [log in to unmask]
(snip)

Then there's the time I pull-started a 7933 spindle motor using one of
my shoe strings, like pull starting a lawn mower.  The 7933s ran for a
long time and the ball bearings in the motor heated up.  When powered
down for a PM, they cooled.  Sometimes when trying to spin them back up,
they wouldn't get up to speed quick enough during the self test so the
self test would fail, not allowing the drive to be used.  I removed my
shoe string, wrapped it around the large nut on the bottom of the disk
pack spindle motor, turned on the drive and pulled as hard as I could to
help the motor get up to speed.  It worked.  Spindle motors didn't fail
that often, so we didn't stock one in our HP office.  Once the drive was
up to speed and passed its self test, the drive could be used for a few
days while I ordered a spindle motor to replace the defective one.
 

Regards,

Steve Gray
Abtech Support
 

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