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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 Richard, 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]> wrote: > 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 >>>>> www.baileyzone.net >>>>> >>>>> 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 >>>>>>> http://www.richardhess.com/tape/contact.htm >>>>>>> Quality tape transfers -- even from hard-to-play tapes. >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>> >>>>> >>>> -- >>> Richard L. Hess email: [log in to unmask] >>> Aurora, Ontario, Canada 647 479 2800 >>> http://www.richardhess.com/tape/contact.htm >>> Quality tape transfers -- even from hard-to-play tapes. >>> >>> >>> >> -- > Richard L. Hess email: [log in to unmask] > Aurora, Ontario, Canada 647 479 2800 > http://www.richardhess.com/tape/contact.htm > Quality tape transfers -- even from hard-to-play tapes. >