Re: Group purchase of Lisa, Lisa 2, Apple II, Apple III, Early Mac Software CD?

["Michael J. Mahon" <mjmahon@aol.com>]

Declan MacLeod wrote:
> In article <j8udnX8sKLnXDIbfRVn-gg@comcast.com>,
>  "Bill Garber" <willy46pa@comcast.net> wrote:
>
>
> > "Tim Haynes" <timhaynes@alumni.no.spam.please.uwaterloo.ca> wrote in message
> > news:cvg2cq$qlh$1@rumours.uwaterloo.ca...
> > :
> > : It wasn't mishandled or anything - just went bad.  Odd that I could get a
> > : directory listing, but nothing else.
> >
> > That IS very odd, indeed. Have you tried making a global
> > image of the CD and burning it back onto better media???
>
>
> I've had a bunch of properly-cared-for CD-Rs go bad.  Apparently 
> adhesive labels are bad juju.  Maybe Sharpies as well...

Roger the problem with adhesive labels.  Apparently, it is all
but impossible to get them _perfectly_ centered, regardless of
the device you use.

When they are not perfectly centered, they cause the center of
gravity (and thus the center of rotation) of the disc to not be
in its geometrical center--or, more to the point, in the same
place it was when it was burned.

The resulting track wobble exceeds the ability of the laser servo
to compensate, and causes unrecoverable errors.

All of the above applies to recordable DVDs, as well--even more so
because of the greater track density.

Sharpies are a problem with CDRs, but not DVD+/-Rs, because the
reflective layer of a CDR is one varnish-thickness below the surface,
while in a DVD there is an appreciable layer of plastic between the
reflective layer and the back surface.

The good (?) news is that a CDR or DVD that has been made unreadable
by an adhesive label can be restored to good health by _completely_
removing the label (_without_ any damage to the underlying varnish,
in the case of a CDR).  Of course, this is easier said than done!

I've had luck with careful, slow peeling on DVDs with a "painted"
label side.  The matte-finish ones are much harder, but I understand
that warm soapy water can be used (though I don't see how it will
cut all the adhesive...).  Alcohol can also be used safely with
DVDs (put perhaps not with CDRs).

If anyone has a good method that works, I have over a hundred DVD+Rs
that I painstakingly put lovely adhesive labels on that I would now
like to remove.  ;-)

-michael

New Applesoft BASIC interface for NadaNet networking!
Home page:  http://members.aol.com/MJMahon/