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Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469
Great discussion! I was looking for a list of the Ampex tape
products similar to the links regarding 3M and Agfa/BASF/IGF tapes?
Also, has anyone seen a site with photos of different tape formulas
that would help identify unknown tape brands/types?
Thanks
Steve Koto
On Apr 3, 2008, at 7:28 AM, Richard L. Hess wrote:
I think the listing on the Ampex site of SSS tapes hits the high
points.
There are multiple issues.
At this point there is one major failure mode for polyester (PET)
base film magnetic tape:
BINDER / COATING SYSTEM DEGRADATION
This can manifest itself in many ways:
(a) Soft Binder Syndrome - I see this as generic where the binder
softens
- on some tapes the glass transition temperature falls to
below room temp
- one instance Tg was +8C measured
- cold playing may work on tapes that don't have other
problems / solutions
- cold playing seems to work now on Sony PR-150 and 3M 175
(b) Sticky Shed Syndrome
- While the binder has gone soft there is far more shedding
than the generic SBS
- Baking or Pellon wiping appears to cure this. I prefer baking
- Baking times are going up
- This appears to work with all of the tapes (except perhaps
Q15) listed on
the Ampex site
(c) Loss of Lubricant
- While theorized, no tape has yet been identified chemically
with LoL
- LoL in concept can be explained by not loss of lubricant
but increase in friction
see (a) and (b) above
(d) Squeal that doesn't respond to (a) or (b) above that while
probably not (c) can
nonetheless be played with additional lubrication be it
isopropyl (Thanks, Kiwi) or
D5 (Thanks, Scott). Search MARIE in my blog
(e) In at least one instance with Shamrock 031 it did not respond
to the indicated treatment
in (a) or (b) but higher speed playing on a different
topology machine Search SHAMROCK
in my blog
Cheers,
Richard