Yes just mentioning the brand of cassette as Ampex helps. It seems
likely yours are one of those few cassette types vulnerable to SSS. Of
the four cassettes I've seen which benefitted from baking, two were
You mention backcoating. I've seen Ampex cassettes but have never
noticed whether they had a black back coating. I did once have a
special test cassette for use in calibrating Audio Telex high speed
cassette duplicators and that definitely had a black back coating.
Perhaps it was Ampex stock.
It'd be interesting to know if others have seen cassettes with a back
coating and what brand they were.
----- Original Message -----
From: "Association for Recorded Sound Discussion List"
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To:<[log in to unmask]>
Sent:Thu, 12 Nov 2020 19:26:34 -1000
Subject:Re: [ARSCLIST] Drying Reel-To-Reel Tape in Food Dehydrators?
Hmmm... perhaps I should elaborate a bit. The cassettes I'm having a
problem with are Ampex 1.5mil cassettes, around 30 years old. They
display sticky shed in that, when I attempt to play one, either the
magnetic coating or the back coating begins depositing itself on the
playback head and high end frequency loss quickly becomes apparent.
in play long enough and the tape begins to drag as more and more of
coating transfers to everything along the tape path - the motor just
cannot keep up with the load.
I've never let it get that far but I know tape and remember the same
thing happening to 2" Ampex 456 back in 1983. I think that was well
before baking became known to work. IIRC, the problems began when
manufacturers removed whale oil from the coating chemistry and they
changed the formula. I remember once opening a new, sealed box of 1"
with the sticky shed already in place! Initially it was believed
upon opening the plastic bag around the reel of tape, the tape
immediately began sucking up moisture from the ambient air and that's
what caused the goo to form.
So, to answer your question Lou, yes I've seen shedding but, correct
if I'm wrong, shedding means that when a tape coating has been
too thickly to the mylar backing and upon first use the tape is
you get a lovely little cloud of dry backing coming off the tape. I
this happen to a reel of 2" around the same time (early 1980s) when
was touting their new tape formulation and sending out samples for
studios to try. One box was enough for me.
My personal tape archive goes back to 1950s 3M acetate reel-to-reel -
which still play well even if any splices have long since given up -
to present day cassettes.
This is a somewhat long way of saying I'll happily give baking a try
that food dehydrators have been proven to work well.
Thanks to all of you for your sage comments and advice!
On 11/12/2020 7:55 AM, Lou Judson wrote:
> I’ve never had a cassette with sticky shed. I have seen problems
with cheap shells and possibly warping. I use Nakamichis so the pads
are not a problem (Naks lift the pad away from the head and use dual
capstan tension for better contact).
> Have you seen evidence of shedding on the machine after playing? or
squeaking as they play? I have had cheap casstes and extra long ones
(such as C-100 and C-120) bind and slow down warbling in speed, and
usually winding forward and back helps, as well as slapping the
casstte flat on a desk to re-align the tape pack.
> Re-shelling is not a bad thing either, just have to be careful with
all the tiny parts.
> Richard Hess might have some deeper wisdom on this, but I have
never had a casstte need baking.
> Lou Judson
> Intuitive Audio
>> On Nov 12, 2020, at 9:37 AM, Malcolm <[log in to unmask]> wrote:
>> One of these units has been on my wants list for quite a while
along with a Keith Monks record cleaner, but in both cases life has
stepped in and said, "No, not yet. I'll get back to you." I have a
number of cassettes that display sticky shed but before baking them
I'd like to know whether there may be a problem with the shell
warping, the pinch pads falling off, etc. Taking the tape pack out of
the shell is certainly an option, but I'd rather not if I can help it.
Suggestions would be helpful. Thanks!
>> Stay safe,
>> Malcolm Rockwell
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