Hi John,
Thanks for your words on using the tape tensioning method which I
hadnt heard of. I did have a similar sticking and tearing problem
with some 8mm camcorder tapes many years ago but the source of the
problem was obvious. There was white coloured mould stuck to the edge
of the tape pack.
What I dont understand here with Richard's tape is the seeming absence
of any material causing the winds to stick together. Whatever the
cause I'd expect to see some evidence of that material on the tape
pack.
Tim.
----- Original Message -----
From: "Association for Recorded Sound Discussion List"
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To:<[log in to unmask]>
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Sent:Wed, 4 Nov 2020 10:51:38 -0500
Subject:Re: [ARSCLIST] Sticky DAT tape.
Hi Richard:
Is it the reel flanges causing the problem, pressing against the tape
at
that spot, or are the windings actually stuck together at that spot?
If
reel flanges, it is worth breaking the top half off? Your problem
sounds
very similar to the same problem we encounter here, from time to
time,
with mold sticking the windings together on metal particulate formula
8mm videotape which is also very thin. Below was my post on AMIA-L
for
this solution. If you've pretty much given up, you might want to try
this as a last ditch effort. Have never done this with DAT tapes
though,
just 8mm videotape......
Kind Regards,
John Schroth
Media Transfer Service
Basically put, the mold has formed, dried and is sticking the outer
edge
of the tape windings together. Since the base on 8mm tape formats is
so
thin, it easily tears horizontally at many spots where the edges are
stuck together by the mold. You don't see this in many other formats
because the tape base is often thicker and more robust. In my
experience, baking does not help loosen the windings and since the
tape
is not suffering from binder hydrolysis, there's nothing gained by
baking.
We have worked for many years to develop a process for separating the
windings that are stuck together on 8mm tape. I first came across
such
tapes almost 20 years ago. A client brought in a bunch of 8mm tapes.
Immediately, the first several tapes tore when we put them in our
decks.
Not wanting to cause further damage, I convinced the client that we
should try sending the tapes to Vidipax, hoping they could work with
them there. Although the engineers at Vidipax made an attempt they
were
having the same results. The engineer there said that they could
spend
some time working on them further but my client didn't want to spend
any
further money. I know that if there were the funds and the interest,
the
great Jim Lindner would have found a way around this issue. They sent
the tapes back and I told the client that we would store them until
we
found a solution.
Several months later we had a large collection of 8mm tapes that came
in
with the same issue. I told the client it would take some time, but
we
would come up with a solution as we could not find any other lab that
was willing to work with these tapes. So I decided to get some 8mm
tape
stock, grow mold on them, let the mold dry and start experimenting.
It
took a long time but we finally developed a process to work around
the
shearing.
A lot of the work is done by hand and requires a lot of patience.
It's
takes about 3-4 labor hours per tape and a ton of space but to date,
the
process is 100% effective with very little coincidental damage to the
tape. It involves a very high degree of break pressure applied to the
payout tape spool as the tape is removed from the spool, just under
the
amount that would stretch the tape. The high degree of tension
applied
causes a harsh angle (almost 90 degrees) as the tape comes off the
payout reel. The harsh angle, in combination with the high degree of
tension to the tape at that angle, safely separates the windings that
are stuck together without the tape tearing/shearing. As you unspool
the
tape you need a place to safely place the loose tape that comes off
the
spool. We have large circular support columns throughout our space
that
are 30' apart. We tape the end of the videotape to one of the columns
and safely unwrap the tape back and forth around two columns as we
unspool the tape. We never touch the tape itself, we're just pinching
the spool between our fingers as we unwind the tape off onto the
columns. As a safety measure, we very carefully use painters tape or
other very light adhesive type tape to secure a very small portion of
the backside of the tape to the column with each wrap as sometimes we
will get an occasional tear and without securing the tape to the
columns
it would all fall to the floor. Then we clean the empty spools and
cassette from the old mold. Finally we carefully and very slowly
hand-wind the tape back on the spool. Many may question the almost
archaic method we're using, but it works and we've been able to
rescue
every single tape that's come through our doors with this problem.
I don't recommend trying this with an important tape. It's not easily
done, you'll get a ton of tears at first - it takes a lot of
experience
to get the pressure and the method right. We have tried many jig
setups
between motion picture film winders to do this more efficiently but
so
far we have not yet found a way to perfectly clamp both the payout
and
takeup reels with this high degree reel of tension, without the reels
coming off center and wobbling as you wind them, thus damaging the
tape
edges as one is winding. I also feel it's important to do this by
hand
because I can directly feel the tension I'm applying to the tape, so
I'm
not taking it past the point of stretching. We're still working on a
better answer for a more efficient winding system but until then, we
can
take in any mold effected 8mm tape, safely unspool it, clean payout
and
takeup reels and the cassette housing, repack the tape so it won't
tear
when playing back and either return the tape to the client for
digitization, or digitize the tape hare at our facility.
On 11/4/2020 7:22 AM, Mint Records wrote:
> Baked for 4 days. Unfortunately it doesn't seem to have worked - or
sticky
> shed wasn't the fault in the first place. I don't know anymore. I
edited
> the tape back together, and deceased to hand wind the tape to see
how it
> was reacting. It gets to the same spot on every turn and the tape
sticks
> and starts to tear again. I'm not sure what i can now do. Perhaps
it's
> beyond help. I'm not sure 4 more days baking will do the trick. It
seems to
> be that it is stuck fast at the top of the reel every so often,
which then
> just rips the tape. A big giveaway that this is the case throughout
the
> tape is that the pack just doesn't move.
>
> Unless anyone has any bright ideas, I think It may be the end of
the road
> for this one.
>
> Richard
>
> On Sat, 31 Oct 2020 at 07:41, Mint Records
<[log in to unmask]>
> wrote:
>
>> Thanks all. Have been baking now for 12 hours.
>>
>> Will let you know how I get in in about 4 days time!
>>
>> Richard
>>
>> On Sat, 31 Oct 2020, 05:20 Marie O'Connell, <[log in to unmask]>
wrote:
>>
>>> I second Matthew - proceed with caution, much caution.
>>>
>>> I would not attempt to take it out of the casing due to the
thinness
>>> of the tape. I would bake it in increments, eg 12 hours, then
another
>>> if needed and so on.
>>>
>>> Have faith, be brave! You can do it.
>>>
>>> Let us know and BEST of luck!
>>> Marie
>>>
>>> On Sat, Oct 31, 2020 at 5:41 PM Matthew Sohn
<[log in to unmask]>
>>> wrote:
>>>> Corey Bailey said: "I have not hadthe success baking DAT tapes
that
>>> Richard Hess has had."
>>>> I say:Well, Richard only cited one instance, which had a 100%
success
>>> rate.
>>>> On Friday, October 30, 2020, 11:33:06 PM EDT, Corey Bailey <
>>> [log in to unmask]> wrote:
>>>> Check your machine!
>>>>
>>>> A DAT that is suffering from SSS or other problems can (and
will) clog
>>>> the heads of your machine which will cause problems with other
tapes
>>>> that may be good. Unfortunately, there is no good way to tell in
advance
>>>> if cassette based media has problems. Fast-forwarding &
Rewinding before
>>>> playing will exercise the tape. Plus, with some listening
practice, you
>>>> can tell a good tape while Fast-forwarding & Rewinding. I have
not had
>>>> the success baking DAT tapes that Richard Hess has had. I've
personally
>>>> had less than a 50% success rate when baking DAT's. That said, I
didn't
>>>> bake them as long as Richard so, that may be the difference.
Know that
>>>> if you attempt to splice a DAT, you will mess with the control
track so,
>>>> the loss will be more than the amount you removed depending on
how the
>>>> error correction circuitry handles the loss.
>>>>
>>>> CB
>>>>
>>>> Corey Bailey Audio Engineering
>>>> www.baileyzone.net
>>>>
>>>> On 10/30/2020 7:10 AM, Mint Records wrote:
>>>>> Hi,
>>>>>
>>>>> Came across an oddity this morning. I've been transferring some
DAT
>>> Tapes
>>>>> when all o f a sudden one snapped. It's a brand i'd never come
across
>>>>> before called "PYRAL". On taking aprt the shell it's clear that
the
>>> tape is
>>>>> stuck together - The original break was a tear across rather
than a
>>> snap
>>>>> and when i tried to loosen the tape on the reel, more started
to tear.
>>>>>
>>>>> It has the appearance of sticky shed, but i've never come
across this
>>> in a
>>>>> DAT before.
>>>>>
>>>>> Has anyone else come across this? Can the tape be baked? If so,
for
>>> how
>>>>> long.
>>>>>
>>>>> If not sticky shed, any other ideas? There is no sign of
anything
>>> being
>>>>> spilt on the tape. All the labels on it are clean and original.
>>>>>
>>>>> I would like to rescue what I can from it although I know a
>>> proportion will
>>>>> now be irretrievable.
>>>>>
>>>>> Thanks
>>>>>
>>>>> Richard
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