exxos's Atari, Amiga & retro forum

Steve wrote: 11 Oct 2021 16:58 Hi guys,

I'm doing some maintenance on a Sony MP-F11W. Followed @exxos guide on it, replaced caps and did all the routine stuff. I noticed the heads are actually making physical contact with the floppy surface, thus failing tests. I understand I can adjust the top head with the spring notches, but it seems that the bottom head is actually hitting the disk! There is even a dark line burned into the head that you can see where it has probably been ruining disks for years.

I can't understand how it is physically possible for the bottom head to be touching the surface of the floppy like that. Any suggestions?


PXL_20211011_155345404.jpg

rubber_jonnie wrote: 05 Nov 2021 09:50 From what I've read, the heads touch the media to read/write, but don't when moving from track to track, so over time they can get dirty.

The black line you're seeing is likely a thin layer of the metal oxide and can be cleaned with IPA and a cotton bud, I've seen it many times.

If after cleaning and servicing it still doesn't work, there isn't a great deal you can do with it.

stephen_usher wrote: 05 Nov 2021 10:03

rubber_jonnie wrote: 05 Nov 2021 09:50 From what I've read, the heads touch the media to read/write, but don't when moving from track to track, so over time they can get dirty.

The black line you're seeing is likely a thin layer of the metal oxide and can be cleaned with IPA and a cotton bud, I've seen it many times.

If after cleaning and servicing it still doesn't work, there isn't a great deal you can do with it.

Ah, you’ve been reading about the early floppy drives which had the ‘head load’ signal and solenoid to raise/lower the head. By the time of 3.5” drives this had gone away to save on cost. The heads are permanently on the surface and held there by a spring. When you eject the disk the transport cage lifts the top head/pressure pad off the disk.

Sometimes that residue takes not only IPA but also an extended period of gentle rubbing with a cotton bud or the flat face of a piece of paper to polish the surface if the drive has been left like that for decades. However, if it looks clean and still doesn’t work then it’s bye-bye drive.