Floppy Disks - Maintenance / Storage / Cleaning Tips
 

This is just a curiosity question.

Recently I got a couple of hundred floppy disks. Most of these don't work when I insert them, littered with bad sectors. However I then put in Workbench 1.3 disk from 1987 and this loaded without any trouble.

This was stored in the same batch (so same ambient). So I was wondering; is it a question of some disks being of better quality then others?

Or this is more related to how data was written to this disks? i.e. -disks written with some disk-drive result with checksum errors when read from a different disk-drive?

Yes, disks had differing quality, but Commodore tended to use low-quality disks, so it doesn't make sense that that one disk should survive.

Also, it seems how many times a disk is written to makes a difference, Ive got stuff thats been written once back in the day and it still works, then lots of disks that have been written over again and again that have loads of errors on them.

I took this video while my drive was making some strange sounds when fed a particular disk;

https://www.dropbox.com/s/vpv6brokgt...iga01.mp4?dl=0

So what exactly is happening here? Where do these noises come from? When I insert a good disk the drive makes no sound, loads nicely. But there are some disks which make disk drives make these strange such sounds.

What causes such sounds?

Maybe mould or other debris on the disc surface? Try pulling back the shutter and see whether the surface looks smooth or if there are matt blotches on it (which would be mould).

The noise can be given by the central metallic circle that has detached itself from the magnetic tape.

But why would a disk with mould or debris make such noise? How does this effect the mechanics of the drive itself?

So that would mean that while the central metallic circle is spinning the magnetic disk is actually not. Is this so?

In this case disk is completely throw away material.

If there was mould on the disc surface underneath the shutter window (but only around that part, not spread all over the surface), when that part moves under the drive head you may hear it, and being rougher it may slow disc rotation slightly. Since the drive spins at ~300rpm (5 revolutions per second) you might hear that rubbing sound pulse about five times per second as the disc spins.

In some cases, if you leave the drive rotating long enough surface debris can eventually be "polished" away by the heads. So if you're trying to create an ADF file from the disk, you might find that after several tries all tracks reliably read without errors, whereas at first it failed.

Great thread title.

Maybe viruses? If the Workbench was kept write protected from day 1, it should be good. Are some of the disks High Density disks? I've heard they don't last as long as the DD ones??

So I cleaned one of the disks with surgical spirit, format with verification worked plus I copied files to it without issue. Next I'll try same method on a disk that makes these strange noises.

Updated to something more descriptive; hopefully...

I use this thread since opening a new thread would be meaningless IMHO :rolleyes

About Amiga cracked floppies, there's an age after which they don't work anymore ? :blased

I mean, it's probably passed actually 30 years since a floppy is written for the first time .... what should i expect when reading it again nowadays ? :confused