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Bad head alignment on 800k floppy drive
Posted by: Ttpilot on 2024-05-24 16:05:00
I recently acquired an SE. The floppy wasn’t working, so I got it out and lubed everything and replaced the wet-cardboard eject gear, which had stripped. The drive takes in disks now, but I always get the message “this disk is unreadable by this Macintosh”. I get this same result from any floppy, including the original system disks. I inserted a blank disk and selected the “initialize” option. The heads moved, then the disk was ejected. The heads touch if the carrier is put in the loaded position, but could they be misaligned
somehow? I’ve attached a video fwiw
Posted by: codevonlux on 2024-05-24 19:25:36
Did you move the Zero Track Sensor (ZTS) during the cleaning? If so then it is most certainly misaligned. Check Zero Track alignment in https://tinkerdifferent.com/threads/superdrive-floppy-maintenance.549/page-2

I followed these steps and fixed a few 800K/1.44M drives.
Posted by: Ttpilot on 2024-05-24 20:27:45
I don’t think I did, but I did remove the stepper motor assembly for cleaning, following instructions on several YouTube channels
Posted by: Ttpilot on 2024-05-25 15:39:26
Did you move the Zero Track Sensor (ZTS) during the cleaning? If so then it is most certainly misaligned. Check Zero Track alignment in https://tinkerdifferent.com/threads/superdrive-floppy-maintenance.549/page-2

I followed these steps and fixed a few 800K/1.44M drives.
I haven’t touched the zero track sensor, but I noticed that the heads don’t meet flat to each other in the closed position. Could that be a problem?
Posted by: codevonlux on 2024-05-25 20:57:17
The photo does not look good. Did you bend the upper part of the head too hard when you clean the head?

Here is a photo of a working 800k drive:


IMG_0950.jpeg
Posted by: Ttpilot on 2024-05-25 21:11:12
The photo does not look good. Did you bend the upper part of the head too hard when you clean the head?

Here is a photo of a working 800k drive:


View attachment 74173
I must have. Clumsy me vs extremely fragile computer part 😱. Should be fun trying to straighten that
Posted by: codevonlux on 2024-05-25 21:13:45
I did destroy one head before the same way. I is pretty much gone. Good luck.
Posted by: Ttpilot on 2024-05-26 13:00:33
I did destroy one head before the same way. I is pretty much gone. Good luck.
Here’s another one. I’ve also got an SE FDHD, but it doesn’t have a functional hard drive. The only boot disk I’ve got is an 800k System 6 floppy. The computer reads it and starts the OS. The menu shows up on the screen; eventually it stops and says it wants to make a small correction to the disk. On my only boot disk? No way. So I don’t know if there’s a problem with the floppy or the drive
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