🚀 go-pugleaf

In article <4002@uhccux.uhcc.hawaii.edu> mikem@uhccux.uhcc.hawaii.edu
(Mike Morton) writes:
>I've had intermittent problems with an 80Mb internal drive in an SE/30.
>It sporadically won't boot.  When it's refusing to boot, running HD SC Setup
>off a floppy tells me there are no "suitable" SCSI devices attached.

This problem seems to be cropping up more and more frequently these days
(I've seen it three times in the last month) so I think it's time to tell
the whole story.

Many drives, not just the Quantums, can suffer from a problem known as
"Stiction."  This is when the head and the media stick together (because they
are so smooth). This is just enough to prevent the drive from spinning up
when it first gets turned on.

The cure for this is quite simple: Simply rap the drive on the side when you
turn it on. Don't be afraid to hit it (after all, if it won't boot, you've
got very little to lose). This will jar the heads loose from the platter,
and the motor will be able to start it up. Note that if you hear it spinning
up when you turn it on, stiction is NOT your problem and hitting the drive
won't help at all.

Interestingly enough, this problem was at the root of LaPine's developement
effort. They built a lifter machanism to move the heads away fromthe disk at
spindown, but they never did get it working quite properly. Now LaPine is
just a memory, so stiction may yet be with us for a while...

>Question: If you seem to have trouble only when booting, should you leave
>your flaky drive on non-stop while waiting for a replacement?  Or will this
>cause the problem to get worse?

If stiction is your problem, this is definitely the answer. It won't have
any effect on the drive at all. Of course, you should get a new drive as soon
as you can.

---
Alexis Rosen
temporarily at spector@vx2.gba.nyu.edu
alexis@rascal.ics.utexas.edu  (last resort)