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bettablue
January 29th, 2014, 08:27 AM
I am replacing the MiniScribe hard disc in my IBM 5161 expansion unit, but still want to see if I can save it by lubricating the spindle bearings. The only problem is that I can't seem to find a thread on how to properly lube these old hard drives.

Is there a good thread for lubing hard drives, or maybe even a MiniScribe service manual that covers the process?

fatwizard
January 29th, 2014, 06:59 PM
Hi Thomas.

I would doubt very much if a factory service manual would give any instructions for lubricating the spindle bearings since they would have considered that a permanently lubricated bearing, and not a field service procedure. It's something only people like us would attempt while trying to salvage an old drive that's way past it's due date. One of the members (might have been ChuckG, but I don't remember for sure) gave some tips on how he did this, and I use a similar method.

With the drive on it's top on the bench, I remove the circuit board, and using a syringe with a needle about an inch and a quarter long (I really need a longer one for this), and containing a small quantity of light machine oil, I snake the needle under the spindle hub getting as close to the center as possible. I inject a small quantity of oil. I then leave the drive sitting like that until the next day. I have actually had this work very well for me on drives with noisy spindle bearings.

However, drives that don't want to spin up after they have been idle for a time are probably suffering from stiction. Typical symptoms would be a drive where you can nudge the spindle hub to get it spinning, then after it has warmed up a bit you can shut it down and it will restart, but then won't spin up the next day. This is often caused by the heads become mired in the platter lubrication that has piled up at the parking zone. This isn't the only cause of stiction, but it is what's happening to my Miniscribe 8425. Once the drive is warm, this old lube softens and the spindle has enough torque to start the platters moving. When the drive is cold, the old lube is too stiff for the motor to break things free.

I have a Seagate ST 125 that suffers the same problem as well. Once again, I can't recall just who posted about this issue with a Miniscribe, but they recommended moving the interrupter on the stepper motor to break it free. Like nudging the spindle hub, this has to be done every time you start the drive after having been off for a while. It would be important that the drive was properly parked at shut down, or moving the interrupter could damage track zero.

Sorry to yammer on so much (tourettes of the keyboard), but I dearly love my old hard drives and would love to help keep them going.

Sadly, I haven't found a way to really overcome the stiction issue. Having to nudge the drive in some way each day you go to use the computer it's in just isn't very practical.

I really hope this helps.

modem7
January 29th, 2014, 09:32 PM
Is there a good thread for lubing hard drives,
An earlier thread that discusses the issue is [here (http://www.vintage-computer.com/vcforum/showthread.php?24710)].

vwestlife
January 29th, 2014, 09:41 PM
To get an old MiniScribe hard drive to go again, ignore the warning not to do so, and rotate the interrupter to unstick the heads from the platters. This is only a temporary fix, though, because as soon as you leave it turned off for a while, it will probably start suffering from stiction again.

bettablue
January 30th, 2014, 11:56 AM
I do believe Fatwizard has the issue nailed down. The definition of "stiction" seems to apply here perfectly. I just happen to have some diabetic supplies including some very old needles I think will be just fine for lubing the spindle. Then too, I'll follow wizards directions for taking care of the stiction issue. I really only need the drive to work long enough to copy everything on it to my new boot drive. That will save me a lot of work later.

Thanks everyone. As usual, I find your advice right on and very helpful.

bettablue
February 10th, 2014, 08:22 PM
Well, I followed everyone's advice, one at a time of course. When I removed the circuit board, I found that the disc underneath spun freely, and didn't make any noise at all. But that was spinning the drive by hand. So then I cleaned and lubed what I could, then buttoned it back up. The drive still made a hell of a racket, maybe even a bit worse, but I can't really tell, because I didn't test the drive with the cover of my expansion unit removed. To continue, I then pulled the back cover, making sure not to touch the platter assembly, and again lubed what could. This time when I put the drive back together and tried it in my XT computer, the noise was about the same, but it did finally spin up enough to boot the computer. However, it only lasted a couple of minutes before I could clearly hear the drive slow, until it finally stopped spinning altogether.

At this point, I'm giving the drive to my imagination and decided to add a bit to my knowledge by completely stripping the drive down to its separate components. At least I might be able to learn something from it before I finally give it to my local recycler. I'm keeping the front faceplate and cage assembly so I can remount the hard disc in my Compaq Portable. At least some good will come out of it.

Thanks again everyone. I kind of knew this drive was on its last leg for a while. And, I should have acted sooner, but I procrastinated, and now I'm having a lot of trouble low level formatting the Control Data hard discs I bought from a member of VCF. Tomorrow Ed, the better half of All Things DOS and I will start kind of early, so we can try to get the two 30 MB hard drives working in my IBM 5161 expansion unit. But that's a topic under a different thread. Once we get Alice working again, I'll be a happy geek once more.

Stone
February 11th, 2014, 03:30 AM
I always thought that the platters from those old drives made some fascinating display pieces. They somehow resemble heavy, golden CDs.

MikeS
February 11th, 2014, 08:05 AM
I always thought that the platters from those old drives made some fascinating display pieces. They somehow resemble heavy, golden CDs.They also make nice wind chimes, aside from the usual use as clock faces and coasters.

Stone
February 11th, 2014, 09:46 AM
Yes, they do have a rather pleasant ring.

geoffm3
February 11th, 2014, 11:35 AM
As these things age and become more rare, I wonder if it would be possible to source some replacement discs for these drives...assuming of course the heads aren't also trashed.

Stone
February 11th, 2014, 11:54 AM
Looking for any in particular? Mike and I have lots of doorstops in the wormhole. :smile:

Chuck(G)
February 11th, 2014, 12:01 PM
About a year ago, I pulled out an old Maxtor XT-1140 drive that I'd used many years ago. On powerup, it looked pretty good, but then after about a half-hour, the drive started spinning more and more slowly. I put it back on the shelf--I doubt that much could be done with it.

Stone
February 11th, 2014, 12:10 PM
I've got several of those that spin fine but won't format. I'm thinking track 0 failure.

bettablue
February 11th, 2014, 02:35 PM
They do make a nice ring when hung up as a chime, don't they?

PhilipA
February 26th, 2014, 07:44 AM
They do make a nice ring when hung up as a chime, don't they?

I keep two on my computer here.. as a demonstration that very flat objects (disc platters are incredibly flat) will "stick" together if you squeeze the air out from between them.

People think there's magnetism involved until they get to try it themselves.

--Phil

bettablue
February 26th, 2014, 09:42 AM
I keep two on my computer here.. as a demonstration that very flat objects (disc platters are incredibly flat) will "stick" together if you squeeze the air out from between them.

People think there's magnetism involved until they get to try it themselves.

--Phil

Sounds like a pretty neat science project! I wonder what else these can be used for. So far we have wind chimes, and vacuum experiment. Are there any other ideas out there? I haven't stripped the drive just yet, so I'm open to try just about anything.

SpidersWeb
February 26th, 2014, 09:46 AM
A common one is to use the platter as a clock.
Or connect the stepper motor to a microcontroller and play music with it: https://www.youtube.com/watch?v=G-rmRmm3bgY
(a few floppy drives are handy for other notes)

bettablue
February 26th, 2014, 10:04 AM
A common one is to use the platter as a clock.
Or connect the stepper motor to a microcontroller and play music with it: https://www.youtube.com/watch?v=G-rmRmm3bgY
(a few floppy drives are handy for other notes)

Keep the ideas coming! I'll choose one eventually. Along the same line, and sort of on topic... What can be done with a failing full height Tandon 360Kb floppy drive? Or is there really anything besides using it for parts to repair another of the same type?

SpidersWeb
February 26th, 2014, 10:51 AM
There is only one thing to do with a failing Tandon FH 360KB - fix it :D
Only time I'd dispose of one for parts / projects would be if the heads were physically damaged.

What's wrong with yours?