Hi Jim:

Just to be clear, are your sticky 3M tapes exclusively 226/227, or other types? Thanks in advance. 
This is a very useful discussion!

-- Tom Fine

----- Original Message ----- 
From: "Jim Sam" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, December 18, 2015 5:30 PM
Subject: Re: [ARSCLIST] Interesting sticky-shed data point


We have excellent storage conditions here and while I see SSS uniformly on
back-coated polyester tapes--most tapes 3M and here >15 years--8 hours
always is sufficient.

Jim Sam
Hoover Institution Library & Archives
Stanford University

On Fri, Dec 18, 2015 at 12:07 PM, Richard L. Hess <[log in to unmask]>

> Tom,
> The one semi interesting data point that I have is that in 2012 when I was
> at LoC, they said that they are NOT seeing the increase in baking time
> requirement that many of us on this list have noticed. I confirmed with
> them that the tapes they are transferring have been in their vaults for an
> extended period of time. They bake 8 hours and the tapes play fine with no
> residue.
> So, I take that to be at least some support for the cold, dry storage
> environment that they have buried into the hillside.
> Nothing scientific, just an overall impression based on a confirmed
> conversation.
> Cheers,
> Richard
> On 12/18/2015 2:24 PM, Tom Fine wrote:
>> One thing I'd like to see tested is whether these dry/cold vaults really
>> make any difference with sticky-shed. I know of a vault that has Ampex
>> 406 tapes, NOS, that have been stored there since the vault was built,
>> either before the tapes were purchased or soon afterwards. Acting on the
>> assumption that all Ampex-branded 406 is likely sticky-shed, especially
>> later-era 406 (which this is), I'd love for a real-deal lab to get hold
>> of one of these tapes and test if it's gone sticky. If it has, I would
>> say the cold/dry vault -- which is likely NOT GOOD for acetate tapes --
>> turns out to be no help to stave off sticky-shed. If the tape, or a test
>> batch of tapes, are not sticky, then we have a proven data point about
>> storage.
>> My overall point is, I think there are still a lot of assumptions made
>> about sticky-shed, which aren't proven and may not be true. The only
>> thing that does seem to be true is that a sticky tape can be baked and
>> it will playback in a mechanically successful manner. As I've said, my
>> experience is that the audio deteriorates after a handful of bakes, but
>> others disagree and I think we all admit we haven't done rigorous
>> science on that.
>> -- Tom Fine
>> ----- Original Message ----- From: "Richard L. Hess"
>> <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Friday, December 18, 2015 2:03 PM
>> Subject: Re: [ARSCLIST] Interesting sticky-shed data point
>> Tom,
>>> It is harder than you think. Work has been done and continues to be
>>> done on identifying, the causation, and the remediation.
>>> Since we have no new tape (only NOS) to play with, controlled tests
>>> are practically impossible. One paper I read on potting compound
>>> hydrolysis, the experimenters made new batches of the polymer to test.
>>> Needless to say, that is more difficult with tape, especially when we
>>> have anecdotal (at least) evidence that the process control was
>>> sometimes sub-optimum. And the looooong time it has been around.
>>> Cheers?
>>> Richard
>>> On 12/18/2015 8:53 AM, Tom Fine wrote:
>>>> I submit, then, that we don't have a clear understanding of what causes
>>>> sticky-shed. Since we know that baking makes the tapes playable, knowing
>>>> the cause may not matter at this point, but it would be good to close
>>>> the circle. I'm surprised the government hasn't spent more time and
>>>> money on nailing this down, given how much instrumentation and audio
>>>> tape is archived. It seems like one of the defense-contractor labs would
>>>> have the chemistry analysis and science expertise to figure this out. It
>>>> seems to have something to do with polymer science, as I understand it.
>>>> But then it may not, since we see that what's essentially the same
>>>> material (tapes from the same batch, assumed from the same rolled out
>>>> mass of slurry) may or may not go sticky or may not go the same amount
>>>> of sticky, under same storage conditions.
>>>> By the way, there seems to be a similar thing with some brown-oxide
>>>> acetate-backed tapes and vinegar syndrome. I told the tale of two
>>>> Audiotape masters made around the same time, but likely from different
>>>> batches, the A and B side masters of the MLP mono "1812 Overture." The A
>>>> side tape is badly decayed from vinegar syndrome. It is actually a
>>>> later-time tape than the B side master because it was mixed at the
>>>> studio (music master combined with SFX master to create LP master),
>>>> whereas the B side master is a first-generation recording, edited into a
>>>> master. Both are Audiotape acetate-backed tapes, which have a track
>>>> record of not going vinegar. So why did one go vinegar and one didn't? I
>>>> think it's safe to assume they've been stored together all these years.
>>>> My experience has been that Audiotape acetate-backed rarely goes
>>>> vinegar, Scotch 111 variants seem to be about 50-50 and are dependent on
>>>> storage conditions, Kodak is 100%, and Irish (pre-Ampex) trends more
>>>> like Audiotape (unlikely to go vinegar unless stored in damp
>>>> conditions). So again, why? We've talked about different impurities in
>>>> the iron oxide in any given batch. Might that also relate to
>>>> sticky-shed, that the impurities in the iron are the actual culprit?
>>>> Both conditions seem to relate to moisture being pulled into the tape
>>>> chemistry.
>>>> Some food for thought, by real scientists. Too bad no one with that kind
>>>> of expertise can get the time or funding to nail down the real answers.
>>>> -- Tom Fine
>>>> ----- Original Message ----- From: "Corey Bailey"
>>>> <[log in to unmask]>
>>>> To: <[log in to unmask]>
>>>> Sent: Thursday, December 17, 2015 11:23 PM
>>>> Subject: Re: [ARSCLIST] Interesting sticky-shed data point
>>>> Back in the day, I had a few occasions where batch numbers were not
>>>>> the same with bulk 1/4" (406 & 456) on hubs. Tape that was on reels in
>>>>> boxes, when purchased in case lots, were consistent.
>>>>> I've also had Marie's experience with Sticky Shed where the same tape,
>>>>> from the same batch (Based on the batch #'s from the tape ends stored
>>>>> with the reels), stored on the same shelf, had different levels (some
>>>>> with none) of SS.
>>>>> Corey
>>>>> Corey Bailey Audio Engineering
>>>>> On 12/17/2015 7:47 PM, Marie O'Connell wrote:
>>>>>> When I was in the States I made a largish order of about 1000 reels of
>>>>>> Emtec 911 open reel tapes.  From memory the boxes contained 20
>>>>>> reels per
>>>>>> box and my immediate boss liked me to record the batch number as part
>>>>>> of my
>>>>>> workflow.  Not all the tapes in the boxes were from the same batch.
>>>>>> We had a situation here where the Mitsui Gold CDR's, shrink wrapped
>>>>>> and
>>>>>> all, not only had pit holes in them on the gold layer, but when you
>>>>>> opened
>>>>>> the shrink-wrap and case they were full of dust!.  We sent them
>>>>>> back but
>>>>>> heard that another institution in Asia had complained about the
>>>>>> pit-holes
>>>>>> and sent theirs back after opening them.  It appears they were then
>>>>>> re-shrink-wrapped and we got them!
>>>>>> The joys of archiving!
>>>>>> Marie
>>>>>> On Fri, Dec 18, 2015 at 3:54 PM, Richard L.
>>>>>> Hess<[log in to unmask]>
>>>>>> wrote:
>>>>>> Tom, what you describe is the theory. I have heard rumours that
>>>>>>> was not
>>>>>>> the case in Opelika. Cases were filled with reels when needed. I
>>>>>>> suspect
>>>>>>> that bulk packs were perhaps a bit more likely to be all the same
>>>>>>> batch.
>>>>>>> How wide were the jumbos in Opelika?
>>>>>>> Cheers,
>>>>>>> Richard
>>>>>>> On 12/17/2015 9:27 PM, Tom Fine wrote:
>>>>>>> I thought the numbers on the box and on the stickers box indicated
>>>>>>>> batch
>>>>>>>> numbers and dates of manufacture, indicating that all pancakes in
>>>>>>>> the
>>>>>>>> box were from that batch and date. At least that's how I always
>>>>>>>> understood 3M and Ampex boxes.
>>>>>>>> -- Tom Fine
>>>>>>>> ----- Original Message ----- From: "Lou Judson"<[log in to unmask]>
>>>>>>>> To:<[log in to unmask]>
>>>>>>>> Sent: Thursday, December 17, 2015 7:54 PM
>>>>>>>> Subject: Re: [ARSCLIST] Interesting sticky-shed data point
>>>>>>>> Tom, is it a documented fact that all (12) rolls (reels or
>>>>>>>> pancakes) of
>>>>>>>> tape in a box would be from the same manufacturing/slurry batch? I
>>>>>>>> never
>>>>>>>> looked, but it would not surprise me if there were different
>>>>>>>> manufacturing runs on the same delivery carton…
>>>>>>>> <L>
>>>>>>>> Lou Judson
>>>>>>>> Intuitive Audio
>>>>>>>> 415-883-2689
>>>>>>>> On Dec 17, 2015, at 4:38 PM, Tom Fine<[log in to unmask]>
>>>>>>>> wrote:
>>>>>>>> Hi Marie:
>>>>>>>> This is very strange:
>>>>>>>>> I have also had reels of Ampex 456 come out of the same box of
>>>>>>>>>> 10 or
>>>>>>>>>> 20 and
>>>>>>>>>> purchased at the same time where 1/2 have SSS and the rest are
>>>>>>>>>> fine!
>>>>>>>>>> I've never heard of that from anyone else. That would almost
>>>>>>>>> seem to
>>>>>>>>> defy all theories of what causes sticky-shed, because one would
>>>>>>>>> assume
>>>>>>>>> by a "box" of tapes you mean a real-deal Ampex case with a batch
>>>>>>>>> number on it. If that's so, it's really freaky that some tapes
>>>>>>>>> in the
>>>>>>>>> same batch (which I think means the same production run of the
>>>>>>>>> chemical slurry) would get sticky-shed and others wouldn't.
>>>>>>>>> I'm not doubting your testimony at all, just saying that is calls
>>>>>>>>> into
>>>>>>>>> question what is believed to be the cause of sticky-shed, in that I
>>>>>>>>> can't see how the binder chemistry could differ within a batch.
>>>>>>>>> --
>>>>>>>> Richard L. Hess                   email: [log in to unmask]
>>>>>>> Aurora, Ontario, Canada                             647 479 2800
>>>>>>> Quality tape transfers -- even from hard-to-play tapes.
>>>> --
>>> Richard L. Hess                   email: [log in to unmask]
>>> Aurora, Ontario, Canada                             647 479 2800
>>> Quality tape transfers -- even from hard-to-play tapes.
>> --
> Richard L. Hess                   email: [log in to unmask]
> Aurora, Ontario, Canada                             647 479 2800
> Quality tape transfers -- even from hard-to-play tapes.