Re: Rotting 5.25 floppies

["winston19842005@yahoo.com" <winston19842005@yahoo.com>]

On Aug 5, 4:00 am, "Michael J. Mahon" <mjma...@aol.com> wrote:
> winston19842...@yahoo.com wrote:
> > On Aug 4, 8:57 pm, bloomer_au <bloo...@iprimus.com.au> wrote:
> >> Thanks for the advice guys.
>
> >> To clarify one point:
>
> >> "> Last night, after I played some Savage Island Part I, I put in a
>
> >>> different 5.25, and it did the screwing my drive routine.
> >> I'm not sure exactly what you mean by this...  Do you mean that after
> >> running this disk, disks that previously worked stop working? "
>
> >> Yes, that is what I mean :) The Scott Adams disk ran fine multiple
> >> times, but then I put this 2nd disk in. The 2nd disk wouldn't boot and
> >> I got 'check startup device!', and then when I went back to the Scott
> >> Adams disk, it wouldn't boot either. That suggested to me the
> >> mechanism of the 2nd disk introducing some crud into the drive. I had
> >> experienced this same pattern of trouble before with several 5.25s,
> >> one standalone and a kind of duodisk thing (unsure of brand) attached
> >> to an Apple II clone. So the pattern has been - disks work, then after
> >> a particular disk is put in (not the exact same one mentioned in this
> >> example) nothing works. Then after a clean or three, maybe I get to
> >> the point where the first disk is okay to be run again. Or maybe
> >> nothing ever works again. And my disks have been stored very well as
> >> far as I can tell.
>
> > Ah, the "Disk of Death" syndrome. It has been documented, by me and a
> > few others.
> > After checking some disks that come out fine, put in another suspect
> > disk. It is unreadable.
> > Suddenly, you go through several more unreadable disks, then try a
> > previous disk, suspecting that something is wrong.
>
> > It no longer works.
>
> > The "suspect" disk "crudded" up your head. When you tried subsequent
> > disks, the "crud" basically sliced into the disk surface and messed
> > them up, including previous disks. Upon close inspection, I've
> > actually seen the disk surface marred after such an incident.
>
> > You may get the drive back by cleaning, you may not. I've gone through
> > several 3.5" drives on my PC because of going through "mystery" disks
> > that did exactly the above. The disks were ruined and I've lost at
> > least two drives that way. Probably wound up ruining the head by being
> > too rough during the cleaning process after a more mild attempt
> > failed.
>
> > A note about disk cleaners - I used to trust them, but the last time I
> > used one it ruined my last 3.5" drive (a new one I had just put in
> > after the previous one failed after a couple of months).
>
> > These are the dangers of going through old disks.
>
> Although this can happen as a result of abrasive contamination
> of a disk or drive, it is a relatively rare occurrence.
>
> There is also nothing subtle about it.  The source of the
> damage/contamination will be grossly obvious if the surface
> of the disk(s) is examined visually.
>
> I would not start to diagnose with this mindset.

But once you've established a pattern of good disks, then suddenly
start having failures, you've either come across a "bad lot" of disks
or you've suddenly had either contamination of the disk drive or a
hardware failure/glitch. Of the 3, the 2nd is the most likely.

I've had a fair bit of experience with this, and have had others
confirm it as well. It happens fairly regularly when you are going
through an old pile of media.

The easy way to check is once you see a pattern of failing disks, take
the "next few" to another system/drive and check them there, if ok see
if it fails on your test system. If it does, visually inspect the disk
and perhaps try it back on the other system.

Of course, you might bugger two drives, but I really think they can be
cleaned.