[unix-pc.general] Hard Disk Won't Spin on UNIX PC

thad@cup.portal.com (Thad P Floryan) (08/20/89)

A lot of the "my disk don't spin" (sic :-) problems are caused by a
manufacturing defect resulting in "stiction".  Essentially what is
happening is the head assembly is being held to the platter(s) preventing
main spindle rotation (due to safety interlocks).  Often just twisting the
stepper motor shaft a wee bit will "break" the stiction and permit one to
power- and spin-up the drive.  Once you do this, backup your data ASAP and
start looking for a new hard drive (or have your present one re-plattered).

Without wishing to get into a long-winded discussion about the problem,
I'll keep this short and state the problem is caused by either over- or
under-lubrication of the platters.  If there's INTEREST (determined by more
than, say, 10 emails), I can summarize and post all the gory technical
details as have been recently hashed-out in another newsgroup.

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

madcat@cbnewsm.ATT.COM (Marty Donaldson) (08/22/89)

From article <21443@cup.portal.com>, by thad@cup.portal.com (Thad P Floryan):
> A lot of the "my disk don't spin" (sic :-) problems are caused by a
> .............  Often just twisting the
> stepper motor shaft a wee bit will "break" the stiction and permit one to
> power- and spin-up the drive.  
> 
I've had this problem with my second hd. Moving the stepper motor shaft has
always worked, but it's not convenient. I have since made it a practice to
always boot the diag. floppy and park the heads after I do a "shutdown".
It has not failed me yet.

Marty