wb1j+@andrew.cmu.edu (William M. Bumgarner) (08/02/88)
a squealing drive usually means that the bearings are going bad. If it is under warranty, replace it before the warranty runs out... if not, don't worry about it for a while. We had a Jasmine DD80 do that; it lasted for over two months before the damned noise got too annoying to deal with. Jasmine quite graciously replaced it. b.bum
jimc@iscuva.ISCS.COM (Jim Cathey) (08/03/88)
In article <AWxSJSy00VsG428qIH@andrew.cmu.edu> wb1j+@andrew.cmu.edu (William M. Bumgarner) writes: >a squealing drive usually means that the bearings are going bad. If it is >under warranty, replace it before the warranty runs out... if not, don't >worry about it for a while. The traditional cause of hard disk squeal is not the bearings, but a static discharge brush pressed against the spindle of the drive. The 'fix' is usually to just rip it loose. No one seems to have an adequate explaination why you need/don't need this thing. This squeal isn't harmful to anything except your nerves. Of course, your bearings _could_ be bad, but it's unlikely. +----------------+ ! II CCCCCC ! Jim Cathey ! II SSSSCC ! ISC Systems Corp. ! II CC ! TAF-C8; Spokane, WA 99220 ! IISSSS CC ! UUCP: uunet!iscuva!jimc ! II CCCCCC ! (509) 927-5757 +----------------+ "With excitement like this, who is needing enemas?"
mo@well.UUCP (Maurice Weitman) (08/04/88)
wb1j+@andrew.cmu.edu (William M. Bumgarner) writes: >a squealing drive usually means that the bearings are going bad. I beg to differ. While I haven't read the original query, a squealing drive doesn't *usually* mean bad bearings. Bearings *rarely* are the problem. It's most likely the static wiper brush, which in most drive designs is a superfluous element, and may be removed without ill effects. Check with the manufacturer. -- Maurice Weitman ..!{dual,hplabs,lll-crg,ptsfa,glacier}!well!mo | <- this is not a pipe 1634 Walnut Berkeley, CA 94709 (415)549-0280 Quote: "If we're not listening, we'd have to be pretty blind." J-L Gassee Disclaimer: Any errors in spelling, tact or fact are transmission errors.
bytebug@dhw68k.cts.com (Roger L. Long) (08/04/88)
In article <AWxSJSy00VsG428qIH@andrew.cmu.edu> William M. Bumgarner writes: >a squealing drive usually means that the bearings are going bad. If it is >under warranty, replace it before the warranty runs out... if not, don't worry >about it for a while. No, it's usually the little static discharge clip that rests on the drive spindle that causes the squeak/squeal. You can usually (if you have an inclination to do so, and 2 months of squealing would certainly give me an inclination to do so) open up the drive and adjust the tension on the static clip to make the drive quiet again. -- Roger L. Long dhw68k!bytebug
dxjsb@dcatla.UUCP (Jack S. Brindle) (08/04/88)
jimc@iscuva.ISCS.COM (Jim Cathey) writes: > The traditional cause of hard disk squeal is not the bearings, but a static > discharge brush pressed against the spindle of the drive. The 'fix' is > usually to just rip it loose. No one seems to have an adequate explaination > why you need/don't need this thing. This squeal isn't harmful to anything You might want to think twice before doing this, and be sure you back up the disk real well if you decide to do it. As the disk spins, the action of the air passing the platters causes quite a bit of static electricity to build up. The graphite button that presses against the spindle allows the static to discharge through a controlled path. If you remove the button, the discharge will still occur, but through places you may not like. The upshot of this is that data will start becoming corrupting or just disappearing from your disk. This can occur quite rapidly, actually. Try it and see the effects after a week or so. (This is where the backup comes in...). There ARE ways to resolve the squeal, such as moving the botton slightly so that the contact point with the spindle is different. Some of the disk manufacturers also have a silicon or graphite grease of some sort that should eliminate (or at least quiet) the problem. Hope this helps. Jack Brindle.
bldflame@pnet06.cts.com (Stuart Burden) (08/05/88)
wb1j+@andrew.cmu.edu (William M. Bumgarner) writes: >a squealing drive usually means that the bearings are going bad. If it is >under warranty, replace it before the warranty runs out... if not, don't worry >about it for a while. > >We had a Jasmine DD80 do that; it lasted for over two months before the damned >noise got too annoying to deal with. Jasmine quite graciously replaced it. > >b.bum This is not always the case. Most of the time, a squeaking hard disk, will be due to the the wearing of the static brush. I encountered this problem on 5 seperate occasions with SuperMac drives. SuperMac have amazingly modular architechture for thier HD's. Basically it is three parts (controller, power supply, hard disk chamber), so it was really easy to pluck the little squealing beast from it's resting place. If you are at all squeamish about opening your breed of HD, then your dealer will probably be able to replace/remove the static brush for you. I gather the idea of the static brush is to eliminate (ground) any static build-up, so it won't go skating across the surface of your HD destroying data on the way. If you look at the circuit board side of your hard disk, you will see what looks like an opening in the board. There is a little cap like affair sitting on top of a bearing.. that is usually the cause of the screech. The NEC chambers that come with the dataframe XP 40's has a little screw that holds it in, so it is easy to remove. I removed mine only after it was blessed and anointed by my SuperMac dealer, so you might like to check on anything that would cause the warantee to be voided (like clipping the staticbrush off, if it is soldered to the PCB etc). Now children, don't you try this at home... :-) Hope this help, Stu. __________________________________________________________________________ ______________ - -- --- / __________ / "Now we send forth Jen. - --- / / # # / / Watch over his dangerous quest" --- -- -- / / / / / - - --- --- / / \__/ / / _________________________________________ -- -- --- - / /_________/ / ARPA: hodge!pnet06!bldflame@crash nosc.mil -- --- -- / # ___ / UUCP: hodge.cts.com!pnet06!bldflame - --- - - /---------------/ INET: bldflame@pnet06.cts.com -- --- - /_______________/ _____________________________________________ All of these opinions are mine and therefore a reflection of my own sanity not necessarily that of anyone else on the face of this earth :-) __________________________________________________________________________
anson@spray.CalComp.COM (Ed Anson) (08/05/88)
In article <7627@dcatla.UUCP> dxjsb@sunb.UUCP (Jack S. Brindle) writes: > >jimc@iscuva.ISCS.COM (Jim Cathey) writes: >> The traditional cause of hard disk squeal is not the bearings, but a static >> discharge brush pressed against the spindle of the drive. The 'fix' is > >You might want to think twice before doing this, and be sure you back up the >disk real well if you decide to do it. I don't know about your disk, but this brush is not universally required. I effectively removed it from my DataFrame 20 a couple of years ago, and it has worked flawlessly (and quietly) since. I seem to recall that it was the manufacturer that recommended this operation. For what it's worth, I didn't actually remove the brush. I simply bent back the copper so that the operation would be reversible. I would recommend that approach, in addition to a full backup. Of course, a full backup is always recommended, anyway. -- ===================================================================== Ed Anson, Calcomp Display Products Division, Hudson NH 03051 (603) 885-8712, anson@elrond.CalComp.COM
ray@mfgfoc.UUCP (Ray Lillard) (08/05/88)
From article <7627@dcatla.UUCP>, by dxjsb@dcatla.UUCP (Jack S. Brindle): > > jimc@iscuva.ISCS.COM (Jim Cathey) writes: >> The traditional cause of hard disk squeal is not the bearings, but a static >> discharge brush pressed against the spindle of the drive. The 'fix' is >> usually to just rip it loose. No one seems to have an adequate explaination >> why you need/don't need this thing. This squeal isn't harmful to anything > > You might want to think twice before doing this, and be sure you back up the > disk real well if you decide to do it. As the disk spins, the action of the > air passing the platters causes static electricity to build up. I removed the @@^%@%@^% spring nearly two years ago on a DataFrame 20 and haven't lost one bit since. I removed it on the advice of a friend who specializes in disk repair and data recovery from crashed drives. Question: Why doesn't the platter discharge through the spindle and bearings to the housing? Is the platter otherwise insulated from the chassis of the drive? I have never taken one of these things apart to look. -- Raymond Y. Lillard FOCUS Semiconductor Systems Inc. net: (sun!daver!mfgfoc!ray) 570 Maude Court att: (408) 738-0600 Sunnyvale, CA 94086 USA
rnv@motsj1.UUCP (Ron Voss) (08/06/88)
In article <7627@dcatla.UUCP>, dxjsb@dcatla.UUCP (Jack S. Brindle) writes: > > jimc@iscuva.ISCS.COM (Jim Cathey) writes: > > The traditional cause of hard disk squeal is not the bearings, but a static > > discharge brush pressed against the spindle of the drive. The 'fix' is > > usually to just rip it loose. No one seems to have an adequate explaination > > to discharge through a controlled path. If you remove the button, the > discharge will still occur, but through places you may not like. The upshot I read somewhere that in the absence of the brush, the static discharges through the bearings, and is not "dangerous" to your data. Anyone know for sure?
cej@ll1a.UUCP (Jones) (08/10/88)
In article <531@motsj1.UUCP>, rnv@motsj1.UUCP (Ron Voss) writes: > I read somewhere that in the absence of the brush, the static > discharges through the bearings, and is not "dangerous" to your > data. Anyone know for sure? It depends. It depends on how much static the platters of *your* drive will build up. It depends on just how conductive the lubrication of *your* drive's bearings is, which can depend on the age of the drive. And it depends how much of a charge can be on the platters of *your* drive before it disturbs the R/W circuitry. From my experience (8 years of hardware support on AT&T, HP, DEC, and CDC products) on literally hundreds of hard drives of all sizes and shapes, I can say, that, yes, it is true, you can *sometimes* remove the spindle ground on some drives and they still work fine. And, yes they are *often* the cause of the "squeak" noise on small hard disks. (Anything used with a Mac is "small" in my mind. "Big" drives are always free standing.) *HOWEVER*, some drives fail constantly without the ground, while the exact type and model of drive, two feet away, works fine without it. And, the fact a drive that works without the ground today does *NOT* mean that it will continue to in the future. (Yes, I have seen several examples of this.) And while you can "read-only" test the drive after you remove the ground, once it is in use, it's first failure could well be on a write. (Though static is far more likely to affect a read operation.) In short: Don't remove it, it's a bad idea. [ Two other ways of looking at it: 1. If it was just a useless hunk of metal, the "bean-counters" would have removed it from at least *some* of the drives on the market. They all ground the spindle in some manner. 2. You back-up your hard drive, right? And, if you don't wear a ground strap, you at least discharge yourself before you play with your memory chips, right? Think of the spindle ground as something in the same class. You *may* not need it, but if you, you *don't* want to find out the hard way. ] ...ll1a! cej [Just me, not AT&T] Llewellyn Jones HASA Qualified - U.S. Approved