Richard is correct about Scotch/3M auto-threading reels. They were and are
a menace. Another bad, apparently untested idea passed off as progress. I used
a few when they were introduced during the 1960s. Some years later I noticed
just what Richard mentioned: the tape on the inside of the spools was sticky
and irremediably damaged. The leaking adhesive had made the coating containing
the sound glue to the top of the layer wound below. My tapes were Mylar, not
acetate, but it didn't matter.
I just transferred a reel of acetate tape that had been stored on a
Scotch/3M auto-threading reel. It has solid sides (no windows) and
three springy clips in the walls near the hubs. From the outside, the
clips are chrome-ish. From the inside they are green.
There was some starting of blocking (layer-to-layer adhesion) of the
wraps of tape near the hub.
There was no significant vinegar smell.
The tape/reel had been stored at approx. 21C 43%RH with limited
swings for the last year, prior to that I don't know, but I think it
had been in climate controlled storage.
I suspect this odd reel is not allowing the centre of the tape back
to breathe much and concentrating whatever outgassing of the tape
pack. Also, another very loose tape pack on the outside (not in the centre).
I'm not sure what this means, but I would think this supports the
need to at least examine the acetate tapes in your collection and
also look especially if you have this reel.
Richard L. Hess email: [log in to unmask]
Media web: http://www.richardhess.com/tape/
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm