I have some non-working auto-inject floppy drives...

[Dennis Nedry]

They prompt me to format every disk I put in. After formatting, the format fails when it goes back to check.

Does anyone have any suggestions? All motors seem to be functioning properly and I have thoroughly cleaned the drives out and re-greased key points with white lithium grease. It seems to be a problem with the heads or circuit board.

MOST of my auto-inject drives are like this. They come jammed with dust bunnies, I clean them all out, and they still don't work.

[Scott Baret]

Are you trying them all on the same computer?

[Unknown_K]

Whta machine did you test them on?

[Dennis Nedry]

I have tested with these machines, but I didn't try every drive in every machine:

Mac IIci
Performa 450 (LC III)
Mac IIsi

Probably more, but that's all that comes to mind... I have tested exclusively in Macs that came with auto-inject floppy drives to begin with. (No "lips" on floppy slot of case.)

[equill]

The sure diagnostic of auto-inject drives is that the hole for manual-eject is in line with the drive's slot. Manual-inject drives have the hole below the slot and just off centre. The IIci is a good bet for testing auto-injects because it normally has one, and its ROM should be savvy. Your experience smacks rather of drives needing a thorough degunking and relubricating.

de

[Dennis Nedry]

Yep, I can tell the difference between auto-inject and manual-inject, and that's a good point you make about the manual eject location. I believe that these are all 1.44 MB drives; I have no reason to believe that they're 800k and I know they're not 400k because there are 2 heads.

Even after thorough cleaning and lubricating, the drives still don't work. I have attempted cleaning the heads directly with alcohol with no better results. I've fixed drives before with this method, but I have a few that just don't seem to work for some reason. It seems that I have about a 50% failure rate with floppy drives in Macs I get, and I can fix about half of them, so I'm stuck with 25% bad drives... This seems kind of like a high failure rate, so I thought I'd ask if anyone has any ideas.

[equill]

If you don't already know of this, by a one-time stalwart of 'Fritter's columns and LEM, it may be of use to you.

de

[Unknown_K]

Somebody posted in a different forum a while back that the 400/800K drives used a floppy cable with a yellow stripe while the superdrives had a cable with a red stripe (cables were different, and maybe told the machine which drive type was connected).

Just an idea.

[Dennis Nedry]

Interesting info from equill and Unknown_K. I'm pretty much certain these are 1.44 MB drives, and the cable I was using most recently has a red stripe. I didn't know about the stripes, though - that's very interesting.

The methods described of cleaning and greasing are exactly what I have done, even the part about WD-40 to clear the old grease, then applying new grease. White lithium grease is what I used which I believe is the original kind used.

I have a feeling that it's a problem with the heads, and possibly a problem with how much pressure the heads are having against the disk surface. On one drive, I wasn't completely convinced it was even touching. That particular one may have been a cheaper manual-inject drive come to think of it.

[tomlee59]

It sounds as if you have done the obvious things. If a thorough cleaning does not allow you to read a disk that has been formatted in that self-same drive, then you have a more serious problem.

From my experience, the next thing you should do is follow up on your earlier observation, and look carefully whether the head is in fact making good contact with the disk surface. In particular, take a close look at the flat copper-ish spring that connects the head assembly to the rest of the drive. Is it creased or torn? If a floppy's metal shutter snags on the head (not as uncommon as one might wish), an overeager user can easily wrench the head assembly. If the head isn't torn off altogether, the spring can tear or otherwise get damaged, preventing the head from properly loading against the disk surface. If the damage isn't too great, you might be able to bend it back into place.

[shred]

It's interesting that you're having problems with the auto-inject drives. I used to find them quite reliable. I couldn't say the same for the manual-inject ones though!

One thing I have found that is "weird" about Mac floppy drives is that when you format a disk, the Mac always seems to take a look at the disk first. Often the Macs don't like what they see and then fail to format a perfectly good disk in a perfectly good drive - in fact they don't even try to format it, but eject it with an error message.

The fix is to erase the disk with a degaussing wand (used for fixing CRT monitors) or a bulk tape eraser. The same disk that no Mac can format will then format perfectly and go on to be used reliably for a long time to come. I "repaired" countless "faulty" floppy disks using this technique back when floppy disks were all the rage (and the disks were quite expensive).

... and if the head gimbal (that copper spring thing the head sits in) is bent or damaged, I don't like your chances of repairing it!

[Dennis Nedry]

Good news

One of the drives mysteriously started to work. I believe I may have gotten WD-40 on the heads and over time it may have evaporated.

The one that didn't look like the heads were touching: Turns out that the eject motor was hung up just right preventing the carriage from going all the way down. This drive is also fixed and the motor is functioning properly.

I think I have at least a couple other drives requiring help, so I'll have to look though and find them.

Thanks again for your help with this!

[Charlieman]

Good luck with the rest, Dennis. A problem that others have not mentioned is a broken size detect sensor (ie a 1.4MB disk is identified as an 800KB disk).

Many years ago, a colleague gave me a 1.4MB auto-inject drive where the head assembly springs had been damaged. The owner had attempted to fix the problem by sticking a UK two pence coin onto the disk head to weight it down. I still own the drive for spares, but I have spent the two pence.

[uniserver]

i just worked on 2 ( super drives on from Classic and one from FDHD) and a Mac SE with 2 800k drives,
i had issues where the drives were not working before and after clean and lube, i found when you take the 2 phillips screws out and pull the top and bottom head out as an assembly there is a spring that is normally completely out of sight unless you pull the whole head assem out...

the spring has a 3 position perch, low/med/high tension settings for clamping pressure across the 2 heads top and bottom,

I found that what ever the setting is, usually low or Med, just move the spring to the next setting (more tension)
the spring seems like they put a dab of epoxy on it, but if you grab ahold of it with some small (electronics) needle nose pliers,
the epoxy will let loose and then you can reposition the spring,

in my case i was able to get all the drives to work, found all this out by trial and error, and literally tearing one of the drives down to all its basic parts.

thanks!