Seagate Reseller News: quotes without comment

[Thad P Floryan]

For the edification of all ... especially those using Seagate hard drives.

the following material is reprinted without permission from the August 1990
"Drive Service News" published by:

	Drive Service Company
	6151 Golfview Drive
	Birmingham, Michigan  48010

``
                     STICTION: What is it?

We use the term stiction fairly often.  Stiction is the term used in the disk
drive industry to identify the phenomenon where the heads get stuck to the
platters.

The primary cause of stiction is clear: too much of the wrong kind of
lubrication on the platters.  Another cause is leakage of spindle motor
lubrication onto the platters.  Lubrication builds up on the heads, creating
a little gum ball; when the hot drive is turned off, the gum ball cools and
sticks the heads to the platter. 

Stiction shows up in three ways:

	- Drive will not spin, because the heads are stuck fast to the media.

	- The stuck heads break free and take patches off the media, as
	  ripping tape off a painted wall will take a patch of paint off
	  (with a patch of plating stuck to the heads, errors multiply).

	- Heads detach from the arm.

Stiction usually occurs on plated media, almost never on oxide media.  Some
manufacturers have few stiction problems, while others have problems with all
drives using plated media.


                     STICTION: What to Do About it?

Unfortunately, YOU cannot do much about stiction.  The only cure is to replace
the platters with ones with little or no lubrication, and clean the heads.
That can only be done in a Class 100 clean room.

When a drive will not spin, you can often retrieve the data using the famous
"kick start".  Rapidly rotate or snap the drive horizontally, so that the
spindle motor acts as a flywheel.  Hopefully, the platters will turn while
the heads remain in place.  DO NOT HIT THE DRIVE; that will cause head slaps.

You may have to do this several times before the drive spins up.  Once the
drive is spinning, back up your data IMMEDIATELY.  If you turn off the drive,
the heads will probably stick again, so either keep it spinning or send it in
for repair.

Seagate 4000 series, ST251/251-1, ST277, and ST100 series drives are noted
for stiction.  Even when the problem was only electronic, as a preventative
measure we replace the plated media in these drives and rewrite the servos,
except on the ST4053, ST4096, and ST4144R, for which unlubricated media is
not available.
''

All the HD repair places in Silicon Valley with whom I checked say essentially
the same thing as does Drive Service Company.

>From my own experience and that of hundreds of thousands of others (and let
us not forget that Apple had to replace over 650,000 drives during 1989 under
warranty due to stiction), the message is clear:

	DO NOT UNDER ANY CIRCUMSTANCES BUY OR USE A SEAGATE HARD DRIVE



Thad Floryan [ thad at cup.portal.com (OR) ..!sun!portal!cup.portal.com!thad ]