> On Apr 6, 2016, at 3:15 PM, JP Hindin <jplist2...@kiwigeek.com> wrote: > > > I had one of those Japanese Koan moments recently when someone asked me "Why > do floppy disks stop working?" and I realised I... didn't actually know. I > thought I'd throw it to the group and get some theories/proofs. > > Let's work on the assumption we're talking about 5.25" and 3.5" disks. > > Several guesses: > - Repeated use slowly wears away the magnetic media layer on the mylar. > - When left in an unprotected state, or a poor environment, damp, mold and > dust can damage the surface, either degrading the magnetic layer or causing > the gap to shrink enough that the drive head physically damages the disk? > - Quantum fluctuations in the state of the universe, caused by millions of > mostly non-interacting particles passing through a disk in any given minute, > alter the magnetic spin of the ferric atoms causing gradual data loss over > time (mostly tongue-in-cheek) > - Given the lack of use of most floppy drives they themselves pick up 'gunk' > and on first reading a diskette after a long time of disuse damage it. > > It _seems_ like when you put a 3.5" disk down for ten years and pick it back > up, a disk that used to work fine no longer does. Of course, after ten years, > it could be your own memory that's failed. > > Dare I ask, what's the consensus? > > - JP
On a related note... What causes an old mfm / roll drive to die if the heads aren't touching the surface except in the landing zone? I have read that it's not impossible for the "pigment" to lose its coercivity over time.