Re: [ARSCLIST] Leader tape

["Richard L. Hess" <arclists@xxxxxxxxxxxxxxx>]

At 10:03 AM 2007-11-21, Dave Nolan wrote:
> I believe there is yet another reason for leader - especially on acetate
> tapes.
>
> My experience is that severe dehydration and cupping of the tape is usually
> confined to the outermost layers of tape, and then usually only when the
> end of the tape has not been taped down with hold-down tape.
>
> Any tapes in our collection that were properly leadered and ends secured
> with hold-down tape exhibit zero cupping.
>
> Just wondering...(perhaps Richard or Eric can give us their scientific
> opinion):  If there is a tendency of paper leader to attract moisture, does
> that make it a low-tech way to keep dehydration of the outer layers on a
> reel to a minimum?

Hi, Dave,

I have seen the same thing with acetate tapes and those made on 7" 
reel (or smaller) recorders have very little leader in the tape 
itself. I haven't studied why the outer layers cup, but I've always 
thought that it was just that a tight wind kept them flat. I've never 
ascribed any moisture-enhancing effects to the leader.

While paper is hygroscopic, I am not sure how much more so it is than 
acetate. Even polyester (PET) is not totally impervious to moisture 
and will apparently "wick" it over time. Much less than the other two 
substances, but I believe more so than PEN that is seeing its way 
into some high-performance tapes.

Cheers,

Richard


Richard L. Hess                   email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada       (905) 713 6733     1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.