Wow that's great! Job well done there. I must admit for a long time I assumed those small caps were no big deal, now I will have to look a bit more closely at failed hardware!

Success!

After installing the drive back in with a floppy inserted at boot... the cat no longer had it's tongue and it wouldn't stop talking, happily chirping away with the reference disk! 😁

Good times! 😀

P.S. If anyone is in the same situ, let me know and I can help those wishing to restore their drive.... it beats $50+ for another one!

Malvineous wrote:

Wow that's great! Job well done there. I must admit for a long time I assumed those small caps were no big deal, now I will have to look a bit more closely at failed hardware!

It's amazing how much hardware can stop responding all because of a blown tantalum or open electrolytic... it's well worth restoring failed hardware with replacement components.

Hopefully the drive will now last another 30+ years! 😁

Nicely done! 😁

What was the exact model numbers of the problematic IBM drives? And are these IBM floppy drives taking standard 1.44MB disks or are they 720KB or 2.88MB? I remember back in the day many of these IBMs seemed to use those IBM 2.88MB floppy drives (usually have a small 2.88 on the fromt of that long eject button) but these had different wiring, so couldn't be used in normal PCs without doing some rewiring. By the time one could get the adapters these drives seemed to have all but disappeared.

And I suppose the older floppy drives would be easier to repair as the later ones gradually evolved to be produced more cheaply, with more integrated and less components that could be replaced (they got less made to last long while the older ones seemed to be better engineered and more complicated in a way).

386_junkie wrote:

P.S. If anyone is in the same situ, let me know and I can help those wishing to restore their drive.... it beats $50+ for another one!

That reminds me, I need to have some work done on my model 30's floppy drive, which is currently in the same situation as your model 80's was - refusing to read anything 90% of the time, even with a good 720KB disk (since it's a 720KB drive) and I'm suspecting capacitor failure, since that seems to be what sidelines these old drives the most. Anyways, nice job! I might be sending you a PM when I decide to get back to restoring that thing... 😀

What was the exact model numbers of the problematic IBM drives? And are these IBM floppy drives taking standard 1.44MB disks or are they 720KB or 2.88MB?

I've had failures in all the variants of the floppy drives that shipped with the PS/2 excluding the 2.88mb drives. The one 2.88 I opened to see why this was the case had no lytics in it at all.

Now, I assume now that your repair is proven to work you will go back and trim the leads a little, right? Those long uninsulated leads are kinda kludgy.

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Most were scrapped because they weren't PC-compatible (differently wired connectors, amongst other things)...kinda funny when considering old games and other software used to be IBM-compatible 🤣!

But respect for anyone managing to fix an old floppy drive! 😁

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Tetrium wrote:

Nicely done! 😁

What was the exact model numbers of the problematic IBM drives? And are these IBM floppy drives taking standard 1.44MB disks or are they 720KB or 2.88MB?

And I suppose the older floppy drives would be easier to repair as the later ones gradually evolved to be produced more cheaply, with more integrated and less components that could be replaced (they got less made to last long while the older ones seemed to be better engineered and more complicated in a way).

Thanks.

I think it was mainly any and all of the drives made by Mitsubishi... the one I repaired was a 1.44MB drive.

I can't comment on any of the other drives but from what I can gather they tend to be a bit more reliable... but at the end of the day, anything that uses electrolytics will need them replaced at some point as the dielectric inside becomes less conductive.

Sutekh94 wrote:

386_junkie wrote:

P.S. If anyone is in the same situ, let me know and I can help those wishing to restore their drive.... it beats $50+ for another one!

That reminds me, I need to have some work done on my model 30's floppy drive, which is currently in the same situation as your model 80's was - refusing to read anything 90% of the time, even with a good 720KB disk (since it's a 720KB drive) and I'm suspecting capacitor failure, since that seems to be what sidelines these old drives the most. Anyways, nice job! I might be sending you a PM when I decide to get back to restoring that thing... 😀

My drive wasn't reading disks at all... so I have a strong hunch that your caps inside are on their way out. Most of these drives are pushing 30 years old... so they've put in a decent shift already.

Yea for sure give me a shout when your ready and hopefully I can give you a hand... cap values, polarity and the likes.

PeterLI wrote:

I was referring to vintage computer hobbyists.

k, didn't know that the number of IBM floppy drives that were left after the initial carnage were diluted even further due to retro computer hobbyists trashing large numbers of IBM floppy drives that had remained, but went defective after the initial carnage.

Years ago I also had the habit of doing lots of smalltalk with people who at the time were into (re)selling old computer gear and he told me he had literally trashed stacks of old IBM computers (many which had 2.88MB floppy drives, as I asked him about these drives specifically) and all went to the scrappers, but he found very few PC ones, most even didn't know these floppy drives were made with PC standard instead of the IBM standard ones. I find it kinda amazing that so many of these IBM systems apparently went to the scrappers and the resellers decided to do so because these IBM computers were IBM-incompatible 😁

CelGen wrote:

Now, I assume now that your repair is proven to work you will go back and trim the leads a little, right? Those long uninsulated leads are kinda kludgy.

Nah probably not, I trimmed the leads quite short already compared to how long they were when they arrived. There was not much room inside the housing so I had to position the caps where there were no obstructions, that and so the case could shut right. It works well, a couple more mm's of the leads won't make any difference, besides... I've got far too many repairs / projects on the go right now as it is and with little time.

386_junkie wrote:

Thanks. […]
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Tetrium wrote:

Nicely done! 😁

What was the exact model numbers of the problematic IBM drives? And are these IBM floppy drives taking standard 1.44MB disks or are they 720KB or 2.88MB?

And I suppose the older floppy drives would be easier to repair as the later ones gradually evolved to be produced more cheaply, with more integrated and less components that could be replaced (they got less made to last long while the older ones seemed to be better engineered and more complicated in a way).

Thanks.

I think it was mainly any and all of the drives made by Mitsubishi... the one I repaired was a 1.44MB drive.

I can't comment on any of the other drives but from what I can gather they tend to be a bit more reliable... but at the end of the day, anything that uses electrolytics will need them replaced at some point as the dielectric inside becomes less conductive.

I have a particular floppy drive which I tested. The floppy was inserted, but as the drive was apparently trying to read the disk, it didn't spin around.

You happen to know what might be wrong with it?
I do have an almost identical floppy drive available I could cannibalize for spares (this drive tested as working).

PeterLI wrote:

Cool! You can easily start a profitable repair service for IBM FDDs. Many have scrapped their PS/2s already because of FDD failure.

That's a shame.

The whole throw away culture gig is a sad by-product of capitalism. First sign of wear 'n' tear... chuck it out and get a new one. 😒

The more these are thrown out and not refurbished... the more valuable the one's still in circulation will be. Already the drives are fetching a minimum of about $50!

Tetrium wrote:

I have a particular floppy drive which I tested. The floppy was inserted, but as the drive was apparently trying to read the disk, it didn't spin around.

You happen to know what might be wrong with it?
I do have an almost identical floppy drive available I could cannibalize for spares (this drive tested as working).

It may not need parts.

Another fault with these drives is a mis-alignment of heads that read the disk... it would be a case of opening the drive and adjusting the drive head to be in-line with the disk, something along those lines anyway... I have not needed to do this (yet) but it may be worth googling.

386_junkie wrote:

Tetrium wrote:

I have a particular floppy drive which I tested. The floppy was inserted, but as the drive was apparently trying to read the disk, it didn't spin around.

You happen to know what might be wrong with it?
I do have an almost identical floppy drive available I could cannibalize for spares (this drive tested as working).

It may not need parts.

Another fault with these drives is a mis-alignment of heads that read the disk... it would be a case of opening the drive and adjusting the drive head to be in-line with the disk, something along those lines anyway... I have not needed to do this (yet) but it may be worth googling.

I know this particular drive wouldn't try to spin the disk around when it tried to read the disk (afaicr the "I'm trying to read the disk"-LED did light up, but it simply did not spin the disk like it was supposed to do). I do have an almost identical drive which I had tested and this one does spin the disk around, so if need be I 'could' replace a faulty part of the non-working drive with one of the other drive...or at least that's kinda what I hope is possible 😜

I don't know how to repair it's failing to spin a disk around without replacing any part of the floppy drive

Tetrium wrote:

386_junkie wrote:

Tetrium wrote:

I have a particular floppy drive which I tested. The floppy was inserted, but as the drive was apparently trying to read the disk, it didn't spin around.

Another fault with these drives is a mis-alignment of heads that read the disk... it would be a case of opening the drive and adjusting the drive head to be in-line with the disk, something along those lines anyway... I have not needed to do this (yet) but it may be worth googling.

I know this particular drive wouldn't try to spin the disk around when it tried to read the disk (afaicr the "I'm trying to read the disk"-LED did light up, but it simply did not spin the disk like it was supposed to do).

I don't know how to repair it's failing to spin a disk around without replacing any part of the floppy drive

Come to think of it... this was the same thing that was happening to the FDD I repaired. It (the LED) lit up but there was no noise coming from the drive, no spinning motor, head reading the disk... nothing.

Changing the capacitors bridged a couple that had blown open circuit and put back into tolerance a couple more... it did the job, from seemingly a dead FDD to a functional one. The capacitors charge up and store current before bursting it back out once a threshold is reached... it is likely that the motor which spins the disk is driven by one of these electrolytics.

Before going and butchering the functional drive... it may be worth your while (and a euro or 2 to buy new capacitors) just to replace them, it sounds most likely to be the fault.

Well done 😀