Talk:Sticky-shed syndrome

Possible bias
I remvoved these two lines from the "conclusions" part of the article:
 * Preservation, however, should be at the highest priority and engineers should be concerned with the maintenance of the original tape.
 * It would certainly be valuable to conclude that safe, environmental control is achievable and that baking should be reserved for only the most dire situations.

because they seemed to be biased, which doesn't seem very encyclopedic to me. Comments? Robaato (talk) 08:44, 30 October 2010 (UTC)

And some more from the "problems with baking" section:
 * This list certainly suggests that baking is not a viable solution for restoration or preservation. If any number of the aforementioned damages by baking can be avoided and the original tape can be preserved, than alternate procedures should be developed to ensure the preservation of the original tapes.

Robaato (talk) 08:48, 30 October 2010 (UTC)


 * I agree, the whole baking section reads as if it has been written by somebody with an axe to grind who is desperately trying to appear neutral and failing. Unfortunately this is one of those subjects that seems to cause people to adopt extreme positions. The article needs to be reviewed by an expert editor. I'll add a POV-check template. --Ef80 (talk) 21:38, 12 November 2010 (UTC)

Also, the conclusion seems biased too (particularly against baking and for hydrolysis). Should this whole section be marked as non-neutral? NicEMyer (talk) 18:18, 3 March 2011 (UTC)

I just think that talking about bias on a page about recording tape is too funny.Popsup (talk) 21:22, 2 October 2012 (UTC)

an email from a group I was on
I did some microscopy of various tapes I was restoring: http://ajawamnet.home.comcast.net/~ajawamnet/SSS_and_Tape_Baking.html [edit- the new link for the microscopy is http://www.ajawamnet.com/ajawamnet/SSS_and_Tape_Baking.html ]Wamnet (talk) 23:03, 1 July 2016 (UTC) not very scientific; but I ended up sending it to a few well known restoration guys; ended up with Dr. Ric Bradshaw commenting, used to be the head of IBM's tape lab.

Here's what he had to say:

""This note contains a great deal of very useful information which could really help you all unravel what is really going on...IF you could actually get some chemical and mechanical analysis of these tapes before and after baking to separate/prove the possible hypotheses that may be at work in these various tape samples.

The Ampex tapes were made using Estane 5701 I am pretty sure...possible a blend of 5701 and 5707....both contain a polyester made from butanediol and adipic acid..the primary difference in the length of the nominal polyester chain....hydrolysis of the polyester-polyurethane cleaves the intial long chain polymerat the polyester repeating units(120,000 Mw or about 340 repeating units long). When the polyester segments of the polyester-polyurethane(PU) is broken down by acid catalysts, water and heat, the coating becomes soft and increasingly cotnains a liquid residue of small polyester fragments. These can pool on the surface and then scrub during tape motion on typical laminated heads used in audio recording such that when the tape stops and reverese direction, the tape slaps down onto the collected adhesive material and picks it up as a "line" or smear of sticky material. We were able to confirm this using high resolution mass spectrometry.

I was trying to get a die made to cut samples for the dynamic mechanical thermal analyzer (DMTA) from the 1/4" tapes Richard sent me before I left IBM..it was never completed by the model shop. I sent Richard's note with the link to Wayne's photos on to Dr Dylan Boday at the IBM Materials Lab in Tucson in the hope that he might be interested in doing some analysis on these tapes samples. He is a new PhD who has joined the IBM Materials Lab in Tucson to replace Dr Wayne McKinley who will retire this year. He is a bright, young enthusiastic polymer chemist who isn't ready to shut off his inquisitive brain and run a mundane materials lab...

What you need to know is what happens to the tapes during baking....chemically and mechanically. I think I know what is going on, but my direct experience was with several binder systems used to make digital 1/2" tapes in the 70's and early 80's...and limited experience with the later versions of Ampex instrumentation and audio tapes (used by NASA). It would be a relatively straight forward analysis which Benoit was doing in France a few years ago..but never go the effort fully completed for these tapes.

What you see visually is surface embossments which show up much better with a scanning electron microscope (also available at the IBM Materials lab)..some of the tapes which had observable "dusting" on the surface are still probably degraded but the dust is not the degraded polyester fragments but the granular ureas from the polyurethane degradation. The polyester fragments are buried within the coating matrix probably due to not being baked or having been run below the glass transition temperature (below 20C) so that the coating is mechanically worn producing the dusting rather than sticky surface conditions. I note what appears to be considerable scratching of those tape surfaces consistent with that type or wear induced damage. The tough components of the binder system are the polyesters..they are rubbery even when degraded somewhat...but the urethane fragments left behind are not..they are called the "hard segments" for that reason..they impart strength but are not elastic. These materials are high melting and would act like grit at the head to tape interface...leading to digital drop outs and SNR degradation, but no squeal or detectable noise in an analogue detection chnanel with the track widths used. The effect of baking at temperatures about 45C is to soften the coating. These tapes have a glass transition temperature detectable by dynamic mechanical analysis (DMTA) typically with an onset of 30C with the viscoelastic transition point (tan delta peak max) close to 50-52 C hence your experimental observation of needing to bake the tapes at a temperature about 50C to see the change in the surface condition. What happens to the wraps of tape on the spool during baking is thermal mechanical creep to relieve the compressive and tension stresses placed in the spool of tape during winding. The surface of the tape coating softens and the topography of a worn tape flows back to a smoother surface due to the compressive forces of the over wraps in the spooled tape during backing. If you back sections of the tape as flat specimens in the oven..not wound against the backside of the overwrap..you would actually see material move to the surface...and probably very little change in surface topography...but change in gloss or reflectivity. I believe your observable staining has a similar mechanistic explanation."

As Richard and I discussed during the creation of his paper, baking does not return the polymer to it's initial condition...just can't happen this way..and once the tape is degraded it is a losing battle to try to "reconstitute it". You can alter it so that it can play, but it's initial durability is gone and it should be copied to a new tape or converted to a digital format."

Wamnet (talk) —Preceding undated comment added 14:38, 24 July 2011 (UTC).

Merger proposal
I propose that Tape baking be merged into Sticky-shed syndrome. The topic of tape baking occurs only in context of the larger syndrome, and baking is already a subsection under the latter article. The Baking article is not so large that the merging, once duplicative material wis eliminated, will cause any problems, Right now we have a situation with similar but non-identical information in two different articles. It would be easier for readers if this were all in one place.Popsup (talk) 21:27, 2 October 2012 (UTC)

✅ -—Kvng 22:21, 12 January 2013 (UTC)
 * support Why else would one bake tapes? Andy Dingley (talk) 00:12, 3 October 2012 (UTC)
 * Support The two topics are closely connected and the two articles share a lot of duplicate information. The Quirky Kitty (talk) 17:56, 12 January 2013 (UTC)
 * Support -—Kvng 21:53, 12 January 2013 (UTC)

more info
I'd like to add in this tape type to the list of offenders... ampex 478. I've been looking at this subject on various fora, & the impression one gets is that 478 is not affected; let me make it very clear, it's actually one of the worst offenders. I have got dozens of reels of 478 1/4" here, & all but three are virtually unplayable.

I am checking to see if I have any quantegy-branded 478; the quantegy/ampex 456 I have seems to be ok. it dates from 1996, right after quantegy took over ampex tape manufacture, & so the box is marked on the front & side as ampex but on the rear as having been made by quantegy. the 'finish' of the paper labels is less 'deluxe' than the ampex/ampex.

in my experience, the oxide surface is not badly damaged, but is coated by the degraded black back-coating. cleaning it off is very labour-intensive & only gives brief respite. the symptoms are squealing of the stationary parts of the tape path (NOT the reels- who wrote that??), occlusion of the head-gaps (& so, loss of signal, especially HF), & possible damage to the deck during spooling as the motors overheat. the squealing sound may be audible as modulation on the output, depending on the exact deck geometry & the amount & type of detritus building up in the tape-path.

I have read elsewhere that besides baking, good results have been achieved by cleaning the tape by spooling gently & not through the normal tape-path, & holding it in a folded terry-towel soaked in "nufinish", which is some sort of car-cleaning product.

here's a link: http://messageboard.tapeop.com/viewtopic.php?t=44638&postdays=0&postorder=asc&&start=15&sid=72bec00101450028edccc76904aedf2d

I haven't tried this yet, but I'm at my wit's end & so this is next. I have some stuff that exists on DAT backups already, so I'll try that first.

final note- ampex introduced a new formulation of video tape in about 1990, available in beta-SP cassettes. I was brought some of this by a sales-rep & we began using it at the facilities house I worked at. within days, we had problems. one machine- a sony BVW-65- picked up so much sticky residue that I had to dismantle it & clean the capstan shaft outside the machine. as I recall, this was a very costly experience for ampex. the same rep brought me one of the cases of 478 at around that time, & a case of the ampex-branded 456 in 1996. the 478 is the stock I'm having trouble with now.

duncanrmi (talk) —Preceding undated comment added 19:54, 3 September 2013 (UTC)

[update] I have devised, after more research- both reading & practical experimentation- a method for dealing with the tapes that exhibit the problem of *back-coating* separation; again, these are tapes where the oxide stays firmly attached to the tape, & the problem is of the antistatic back-coating (usually black, from the high carbon content) coming unglued & redistributing itself onto the working surface of the tape, with the binding agent causing friction/stiction problems for the deck.

in short, I pass the tape back & forth on a deck at high speed, bypassing the entire transport & just using the reel motors, while pinching the tape into a cotton pad soaked in white spirit (naphtha). I do this several times until the pads come up clean. while the tape is spooling this way, one can feel the hardened lumps of deposited back-coating pass through the pads. occasionally, with a bad tape, it is necessary to run both surfaces at high-speed across the edge of an editing blade to remove the hardened material from the oxide surface. with caution, it is possible to recover the tape to perfectly playable condition, although one should be prepared to stop & restart the playback several times to clean the play head of the small amount of debris that still accumulates even after this process. the other symptoms- stiction, squealing & so forth- are now absent. with the 478 I have been processing this way, there has been no damage whatever to the oxide surface or the content of the tapes, & I have been able to digitise the material successfully, with the caveat that some repairs may be needed as the tapes are stopped for head cleaning. I have pictures of the process if they could be of any use to another archivist/librarian.

duncanrmi (talk) 10:53, 3 December 2013 (UTC)


 * Interesting but be aware that you're probably going to run up against original research and reliable source restrictions if you add this material to the article. ~KvnG 15:05, 6 December 2013 (UTC)

I appreciate that, but there's so little research being done by anyone in this area that it's difficult to see how I could get any of my own findings or experiences ratified to meet wikipedia's lofty standards of verifiability.... but I'm happy for it to stay here on the talk page for now; anyone that's seriously interested in this matter will swing by & see it. I find myself explaining this 'back-coating' disintegration issue over & over, with folks saying "why don't you bake it?"; baking the tape would cook the carbon compound into place, on the wrong side (the oxide surface) of my tapes, & that's... um.... not ideal.

duncanrmi (talk) 23:47, 8 February 2016 (UTC)

The solution for the WP:OR etc. issues raised above is to publish your findings in a peer-reviewed journal or give a paper, e.g. at an AES convention. There are quite a few like that, and when I have time I will add references. My conclusion is that *all* back-coated tape from that era has or will develop SSS, it just may take longer. Recent work with some Quantegy and BASF digital audio tapes has proven this to my satisfaction -- tapes that would play with lots of errors before baking, and almost none afterwards. Altaphon (talk) 00:28, 27 October 2016 (UTC)

Guy X Bs, I have over 40 reel to reel tapes some dating back to the mid 60s which I recorded in Japan while the service. These tapes include Sony, Ampex, and Scotch.I have experienced in most of this old tapes your S.S.S.. Baking is one thing I will not be doing because of the bad results. So, what I have been doing is ready for this.. 1.. Running the tape fwd and back one or two times, spraying with Isopropol alcohol, cleaning all surfaces with alcohol 91 percent, then running tape. I believe it helps clearing the problem... moisture from the tape. I have converted a lot of these tapes to cd. Hopefully I will have something to listen to when really get old ha ha.If anybody out there in cyber land, I,d love learning from you. drw/hickorync .davidwinn926@gmail.com 2600:6C5E:4200:378B:F838:AC22:402A:F5B1 (talk) 04:36, 11 February 2021 (UTC)

Agfa
I have a number of reel to reel recordings made in the 1980s on Agfa tape stock. When transferred to digital in the mid-2000s a few of these exhibited tape squeal, identified here (though I didn't know it then) as a symptom of sticky-shed syndrome. Agfa is not identified as an offender in the article, but judging from my own experience I suspect there may be evidence to support its inclusion if one knows where to look for it. Lee M (talk) 23:16, 3 October 2014 (UTC)
 * There is some anecdotal evidence of problems with thinner Agfa formulations from the 80s such as PE46. Reports are thin on the ground though, which suggests that problems are much less common than with the notorious Ampex professional formulations. I've not come across any reports of misbehaving PE36 (the standard Agfa domestic/semipro tape of the 70s and 80s) but even that doesn't mean that all 40 year old tapes will play perfectly, regardless of how they've been stored. --Ef80 (talk) 21:07, 22 August 2015 (UTC)

External links modified
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 * Added archive https://web.archive.org/20071012122634/http://www.amianet.org/publication/resources/guidelines/videofacts/commonprobs.html to http://www.amianet.org/publication/resources/guidelines/videofacts/commonprobs.html

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Spelling
The form "sticky shed syndrome" (space, not hyphen) seems significantly more common, in real-world usage. 2A00:23C5:FE0B:700:D4B6:3542:D9B0:2A73 (talk) 22:26, 25 November 2019 (UTC)

"Baking is also much less effective with u-matic tapes"
Article says that "Baking is also much less effective with u-matic tapes as the cases for those tapes prevent effective heat dispersion within the tape media."

This is uncited, and if the tape was important enough to warrant the effort of baking, couldn't the cassette shell be disassembled to get around this to some extent? Ubcule (talk) 15:11, 14 December 2019 (UTC)