Who would "advocate" fast-winding or playing a sticky tape before it is baked? That is idiotic
advice and should be ignored! The tape is _STUCK_ (ie "sticky") and it will _SHED_ (ie layers of the
tape will separate) if the tape pack is molested until it has been baked and cooled. I've never,
never had a problem with tapes de-layering after they've been baked the proper time at the proper
temperature. I have had tapes (Scotch 227, 3600' reels) that still deposit moderate amounts of white
goo on the guides after proper baking and cooling, but they played back fine (there wasn't enough
goo to jam up the tape travel).
I can't understand why there is still any "debate" about this -- a sticky-shed tape needs to be
baked before anything is done to the tape pack (playback, fast-winding, etc). The good news is,
plastic reels can withstand recommended baking temps and times, and if they end up a little warped,
just gently/slowly spool the baked tape onto a new reel and dump the warped one. If the tape is on a
hub, I recommend you place a flange under the hub, bake it and then handle it very carefully because
baking tends to result in a loose tape pack.
-- Tom Fine
----- Original Message -----
From: "Nigel Champion" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, February 08, 2012 3:32 PM
Subject: Re: [ARSCLIST] Tape Backcoating
Perhaps the problem here is not that the tape was baked but that it was re-wound before baking! I
cringe when I see this advocated.
Pressure on inner windings in conjunction with sticky shed syndrome can create a core as solid as a
hockey puck, especially if storage conditions have been sub-optimal. In such situations, pinning
and delaminating is almost inevitable.
Good luck
Nigel
Nigel Champion
Archive Manager & Audio Conservator
Archive Of Mâori & Pacific Music
The University of Auckland
Private Bag 92109
Auckland 1142
Tel: 64-9-373-7599 ext 85008
Fax: 64-9-373-7441
Web: http://www.library.auckland.ac.nz/ampm/
-----Original Message-----
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of
Jim Lindner
Sent: Wednesday, 8 February 2012 6:41 p.m.
To: [log in to unmask]
Subject: Re: [ARSCLIST] Tape Backcoating
The backcoat binder system chemistry is in most cases similar if not identical to the oxide binder
system, so it sounds like you really do have a mess. Removing one without damaging the other will be
extremely difficult. It may be that using a pellon wipe to try to remove it not chemically, but
through successive wipes at high speed MIGHT remove enough of it to allow playback, but I would have
to see it to tell. It also might be that a low concentration of a solvent will remove the "low
hanging fruit" first - so again a pellon wipe with a dilution of solvent and water might work -
although you then have the rh issues to deal with, which might also cause problems. These are the
"fast and cheap" approaches that might work - but then again you have tried fast and cheap already
and have reaped the rewards.
In the past I have used modified film rewinds (with a NAB hub to accommodate tape) and placed the
supply reel on one side and the take up reel on the other side - oxide side up in your situation. In
between you have your work surface, and you now hand "polish" the tape using a solvent. Unofficially
I might suggest experimenting with the now banned 1:1:1 trichloroethane using this modified film
rewind approach. Although banned, it may still be available in small quantities from chemistry
supply facilities, and yes it is expensive. Fortunately you do not need much. Read the MSDS very
carefully, handle very carefully, adequate ventilation, follow all guidelines, hands end eye
protection, ventilator - all of it. This will be a slow hand process. As you get experience you
will be able to remove the goo and if you are careful in your application leave the stuff under it.
Too much solvent and too much pressure and you will wipe all of it. You "polish" slowly foot by foot
winding the completed and clean tape on the take up side. Based on your description you will need to
also clean the back coat side because it sounds as if you have softened it enough so that it will
reapply itself to the oxide if rewound on it directly based on the pack pressure.
Yeah, well you really do have a mess and a science project. This is just one reason why I am not a
big baking fan. There are not too many cases where I see media that is dumpster bound. Next time you
might consider cleaning before baking.
Jim Lindner
Email: [log in to unmask]
Media Matters LLC.
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On Feb 7, 2012, at 5:18 PM, Martin Fisher wrote:
> Hey Guys,
>
> What chemicals are good to strip backcoating off reel tapes.
>
> NO! NO! NO! I don't want to send them out for stripping. Way too expensive. I don't even want
> to strip the entire tape.
>
> What I need is to clean the backcoat off the oxide layer. The tape was given a "B" wind after
> developing sticky shed and, in places, some backcoating "hairs" got stuck between adjacent layers
> and adhered to the binder. This was exacerbated further by baking. The stuff just turned to goo
> and spread out on the surface of the binder like butter on bread in the oven.
>
> Alcohol works but also dissolves the binder an many instances. No way of knowing the tape stock
> since the boxes are generic, reels are haphazard but the backcoating is of the thick, matte
> gooeyer variety.
>
> Any help appreciated! :-)
>
> Martin
>
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