Xref: utzoo comp.sys.att:9501 unix-pc.general:5383 Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!fernwood!portal!cup.portal.com!thad From: thad@cup.portal.com (Thad P Floryan) Newsgroups: comp.sys.att,unix-pc.general Subject: Re: yet another UNIXpc HD tale Message-ID: <29585@cup.portal.com> Date: 4 May 90 08:31:11 GMT Organization: The Portal System (TM) Lines: 69 Re: yet another UNIXpc HD tale comp.sys.att,unix-pc.general wjc@ho5cad.ATT.COM (Bill Carpenter) in writes about his problems with a Seagate ST251 HD. Sigh. :-( I had ten (10) of those suckers go belly-up on me, all after about 14 months (two months after warranty expiration). And I was in contact with the QA mgr of Seagate in Scotts Valley CA and design engineers also at that facility to rectify the problem. Let's just say that I'll *NEVER*, *EVER* buy anything mfd or sold by Seagate again; and I was deeply saddened to hear of Seagate's acquisition of Imprimis (CDC's disk drive facility). At present I stick with quality drives such as Maxtor, Quantum, and Conner. As I've posted to numerous newsgroups over the past several years, the problem is a manufacturing defect; specifically "stiction" caused by excess lubricant on the platters causing the heads to be "stuck" when they're parked. Not to bore everyone again (though I have probably close to 1Mbyte archives on disk problems of this nature), the solution is to either junk the drives or to have them replattered; nothing else will FIX a drive with the problem. There IS a temporary solution which will permit you to spin-up the drive and retrieve your files. Believe me, I was sweating icicles before I stumbled on this solution several years ago. *ALL* hard drives WILL FAIL; the only unknown is "when?" Thus, I have NO sympathy (anymore :-) for anyone who doesn't have and uphold a HD backup regimen. With all that said and done, here's how you can get the drive to spin up to where you can retrieve your files: Remove the ST251 drive from your system. Turn it upside down so that you see the printed circuit assembly. Notice there's a center spindle which is the main shaft, and off to the corner is another spindle which is the stepper motor shaft. Put the tip of your index finger on the stepper motor shaft and twist it back and forth a few times; you don't have to twist too far, and BE GENTLE ... your data IS still on the drive! Remount the drive into your system, power up and boot, then get your files off ASAP. What you do with the drive after this point is up to you. There are many companies which will replatter your drive. The specific problem (as seen under microscope) with the ST251 is excess lubricant collecting in the PARK area ('cause the heads during normal operation push the excess out beyond cylinder 0 and INTO the center area (the PARK zone) much like windshield wipers on a car's window) and a meniscus forming which effectively "glues" the heads into the PARK area. As I wrote to Usenet (and later found plagiarized in several technical mags), you can demonstrate the phenomenon using two glass plates and a few drops of water: place the dry plates together and note you can slide them around easily; now put a few drops of water between the plates and just TRY to move or separate them. Most of the ST251 that fail are assembled in Singapore based on hundreds of e-mail replies I've received; assembly line workers are over-lubing the platters and the (sloppy or non-existent) QA doesn't detect the problem since it's not until the drives are in service for awhile that a noticeable excess accumulates in the PARK area. The lubricant is "normally" one or two mono-molecular layer(s) thick; the defective drives exhibit signs of more than 5 layers of lubricant. The lube CANNOT be removed inexpensively hence the need to replatter if you still wish to keep the drive. Thad Thad Floryan [ thad@cup.portal.com (OR) ..!sun!portal!cup.portal.com!thad ]