I thought this was an interesting discovery if you're willing to sacrifice the media
to recover
some data.
I've been trying to read some nasty old 360k 5" floppies circa early 80's,
the kind that squeek and
strip the oxide off in nice little rings. These were probably made from the same nasty
stuff they made
early 80's magtapes out of.
Thinking this might be a dirt/lubrication issue, I tried applying whiteboard cleaner to
the disk
while still in its sleeve using a lint-free cloth across the slot on both sides, rotate,
repeat
around the whole disk, and after a few head cleanings was able to recover the data (and
the squeeking
stops).
Weber Costello Markerboard Cleaner (from the label, after water)
octylphenoxy polyethoxyethanol
trisodium phosphate
ethylene glycol
monobutyl ether
it's probably the glycol acting as a lubricant