Mike:
We developed a procedure at
our lab that usually works (about 80% of the time) with tapes suffering from
binder-base adhesion failure. We call the procedure "cold desiccation" and
it takes about 60 to 90 days. The two keys are to greatly reduce the RH in
a chamber to force cross linking while simultaneously reducing the temperature
to loosen the pack.
Of course if the oxide has
already come off, it doesn't work very well - don't know of anyone who can
retrieve a signal off "clear base" but it would be a neat trick (sorry, poor
attempt at humor this last part).
Peter Brothers President SPECS BROS., LLC (201)
440-6589 www.specsbros.com
Celebrating 20 Years of Restoration and
Disaster Recovery Service
In a message dated 2/2/2004 1:04:07 AM Eastern Standard Time,
ArcLists@xxxxxxxxxxxxxxx writes:
I think there are many people on the list who can gently play
tapes. I can on Studer (A810 or A807) or Sony (APR-5003V) equipment. I've
played tapes dating back to a 1935 Carbonyl Iron tape, but while I've had
to sweep up after them, I've not encountered an early tape with oxide
totally flaking off. This is very interesting.
*******************
I have found reels of the cheap green boxed "Shamrock" brown oxide mylar
tape that shed oxide in sheets leaving clear base. That is probably why
it ended up in those boxes.
The oxide sheets just fell off as the tape was unwound; no bond to the
base at all. It would be very hard to salvage.
Mike Csontos
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