[vcf-midatlantic] Getting Data off old Atari Floppies

[Kyle Owen]

On Mon, Dec 14, 2015 at 1:47 PM, Herb Johnson via vcf-midatlantic <
vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:
>
> > Supposedly (Based on info from Chuck Guzis/sydex, though I've never
> > tried this myself), if you dismantle the floppy by cutting open the
> > vinyl case and removing the "cookie" inside, and put it on a baking
> > sheet and bake it in the oven at 300F(?) for maybe 8 hours, they can be
> > made readable again. You may need to apply some sort of sealant to the
> > outside of the disk after baking.
>
> This is, to be polite, flawed advice. There may be some confusion about
> "baking" 1/4" audio magnetic tapes - I have no details about that process.
>
> The diskette Mylar cookie will distort with heat - period. So will the
> plastic envelope. Distortion temperatures are likely above, 120, 130
> degrees F. I don't know the minimum. Storage above room temperature is not
> recommended.
>

I thought 300 degrees F is a bit high, personally, but looking at DuPont's
datasheet for Mylar, it looks to me like it can quite easily handle it. It
has a melting point of 489 degrees F, after all. The shrinkage specs also
look quite respectable; it looks like you can expect 2% shrinkage at 300
degrees F.

That being said, most procedures I see for baking tapes rely on 130 degrees
F. http://audio-restoration.com/baking.php for instance, cites 130 degrees
F as being a good target temperature.

Regarding the envelope: he did say to cut open the "vinyl case" and remove
the cookie.

Might be worth a try on those nasty Wabash disks.

Kyle