Hi, Jim,

That is a great thought but what we're trying to do with cooling the 
tapes is this.

It turns out that the glass transition temperature (Tg) of the mag 
coating has dropped, so  instead of being glass-like at room 
temperature, it's rubbery. Ric Bradshaw, while he was still at IBM, 
measured the Tg of one mag coating at about 8 °C  The idea of cold 
playback is to keep the tape below its CURRENT Tg, so that means 
lowering it substantially below ambient, right into the dew point of 
many studios.

The portable ice maker is a real step up to making Tim's and my idea a 
possibility, and coupling that with the block cooler might be useful. 
But it's hard to get the cooling into the heads and guides on most tape 
machines. The heat tubes used in laptop cooling are other options, but 
the problem is getting it cold enough for the tape to be below its 
current Tg. As I said, one was measured at 8 °C and one experiment at 
Indiana U had the machine and tape soaking at 4 °C over a weekend before 
it worked.

Tg is a measurable parameter but it is a symptom that is being treated, 
not the actual problem. there has been no real chemical research into 
it. There is speculation that this is an artifact of long chain scission 
in the degradation process.

Good hearing from you.

Cheers,

Richard

On 2021-02-26 4:18 p.m., Jim Lindner wrote:
> Based on the conversation, a "water block" that is used for cooling 
> CPU's might be something to consider, certainly more convenient than 
> bringing an entire machine into the cold. It depends on what exactly 
> you are trying to cool down. If it is a head I think it likely that 
> you can position a water block on the head to allow for thermal 
> conduction. The block will act as a thermocouple to pull the heat away 
> from what ever it is attached to - so it wont refrigerate anything, it 
> should work to keep the head at ambient temperature - more or less. 
> There wouldn't be any condensation issue either.
>
> Since there isnt any electricity in the block I can't see any issues 
> with hum or interference. The blocks are generally the size of a cpu 
> but the construction is very simple and one can probably cut one to 
> size with a bit of effort. The tubes to the fan could likely be easily 
> extended to a place where you cant hear it, similarly  power can be 
> supplied by a very inexpensive PC power supply located as far away as 
> you wish.  They are simple and inexpensive devices, and since the 
> amount of thermal energy you are removing is small, it may be 
> something worth trying. Most of them are also quite inexpensive. Here 
> is an example:
>
> https://www.bestbuy.com/site/corsair-hydro-series-120mm-radiator-cpu-liquid-cooling-system-black/5845215.p?skuId=5845215&ref=212&loc=1&ref=212&loc=1&extStoreId=373&ref=212&loc=1&gclid=CjwKCAiA1eKBBhBZEiwAX3gql0wPQe-FaFUhVPzdZDvCH5fwKGCBSJE6EhKdauTEHQlVvZ2_aHNUcxoCyckQAvD_BwE&gclsrc=aw.ds 
> <https://www.bestbuy.com/site/corsair-hydro-series-120mm-radiator-cpu-liquid-cooling-system-black/5845215.p?skuId=5845215&ref=212&loc=1&ref=212&loc=1&extStoreId=373&ref=212&loc=1&gclid=CjwKCAiA1eKBBhBZEiwAX3gql0wPQe-FaFUhVPzdZDvCH5fwKGCBSJE6EhKdauTEHQlVvZ2_aHNUcxoCyckQAvD_BwE&gclsrc=aw.ds>
>
> A step up in cooling power might be to add some low level 
> refrigeration to this rube goldberg idea. There are now many small 
> inexpensive ice machines made these days.
>
> https://www.bestbuy.com/site/insignia-26-lb-portable-ice-maker-silver/6331583.p?skuId=6331583 
> <https://www.bestbuy.com/site/insignia-26-lb-portable-ice-maker-silver/6331583.p?skuId=6331583>
>
>
>  A very inexpensive source of cold. I don't think I would want to mess 
> around with the closed circuit refrigeration circuit ... but as a 
> "source" of cold.... Perhaps combining 2 water blocks in series, one 
> at the point of friction and the other attached on the coils in the 
> ice machine might work to cool down the head. Definitely a DIY project.
>
> Jim Lindner
>
> On Fri, Feb 26, 2021 at 2:43 PM Richard L. Hess 
> <[log in to unmask] <mailto:[log in to unmask]>> wrote:
>
>     Sony PR-150 and Graham Newton's binocular microscope and some dental
>     tools were the first clue to me of soft binder syndrome.
>
>     Marie had said to me she's using wet playback much less. You might
>     ask
>     her to confirm, as I discussed it with her a few years ago.
>
>     Regarding IPA/ISO vs D5: D5 doesn't stink. It's not as harmful a
>     chemical to me. It evaporates more slowly, but does evaporate. It is
>     more of a lubricant than a solvent. It doesn't seem to dissolve
>     anything.
>
>     Regarding cold playback.
>
>     A friend of mine in Pennsylvania puts his machines on the deck
>     outside
>     his office on cold crisp late fall days and it works great, though a
>     killed his Studer C270 ? machine, it works well with his APR-5000. A
>     Studer A810 was unhappy in the fridge--the capstan seized up.
>
>     I have thought of the Peltier effect module and was thinking of
>     dismantling a cooler I haven't used in a quarter century but when I
>     thought about it, it didn't make sense because where does the
>     condensate
>     go? Cooling down to freezing is below the dew point of my air most of
>     the year (40 % RH and a bit higher in summer and a bit lower in
>     winter).
>
>     Using http://www.dpcalc.org/ <http://www.dpcalc.org/>
>         Air: 20 °C   30 % RH      DP: 2 °C
>         Air: 20 °C   40 % RH      DP: 6 °C
>         Air: 23 °C   40 % RH      DP: 8 °C
>
>     Providing thermal conductivity from the Peltier module to the head
>     and
>     guides is difficult. Equally difficult will be the provision of
>     thermal
>     insulation of the cooled surfaces to that giant heat generator
>     they are
>     sitting on (aka the tape deck).
>
>     Prechilling the tape might work for only a few minutes. There isn't
>     enough mass in the tape to stay cold very long.
>
>     I do like your creative thinking. I can't think of how to emulate the
>     tunnel.
>
>     Cheers,
>
>     Richard
>
>
>
>
>     On 2021-02-25 9:33 p.m., Tim Gillett wrote:
>     > Thanks Richard and all for the replies.
>     >
>     > Even though I've not modified a machine as Marie did in NZ, I
>     continue
>     > to wonder about the wisdom of the whole "lubrication" technique
>     except
>     > perhaps as a last resort when all other techniques such as
>     baking and
>     > cold play have failed, and I mean really failed not just because not
>     > implemented well enough, or the limits of baking or cold play have
>     > been reached.  Especially since apparently the problem is not "lack
>     > of lubrication" as such but more "soft binder".
>     >
>     > Richard you said, "While I love the initiative demonstrated by
>     Marie's
>     > isopropyl drip
>     > method (which she has indicated she's moved away from) I found
>     better
>     > results with decamethylcyclopentasiloxane (D5, cyclomethicone,
>     > CAS 541-02-6."
>     >
>     >   In what ways was D5 superior to Iso?
>     >
>     >   I' m also  not sure what Marie has "moved away from". The drip
>     > application technique? The use of Iso?   Wettting technique itself?
>     >
>     > Given that it's not really a loss of lubricant but "soft
>     binder", and
>     > that my experience so far has demonstrated on both cassettes and
>     open
>     > reel tapes A MARKED LOSS OF HIGHS DUE TO SPACING LOSS, I'm
>     tempted to
>     > abandon  tests with wettting the head/tape interface and instead
>     > concentrate on mere cooling of the tape especially as it interfaces
>     > with the repro head.
>     >
>     > I read of  practical problems trying to run an open reel machine
>     > inside a fridge. Do we need to limit ourselves to that approach? The
>     > entire machine doesnt need to be cooled, only the tape and repro
>     head,
>     > and the minimum number of tape guides upstream of that repro head.
>     > Why not pursue techniques which ONLY COOL WHAT NEEDS TO BE
>     COOLED and
>     > leave the rest of the machine unmodified and at usual room
>     > temperature, able to be used and monitored in the normal way?  Has
>     > anybody pursued this?
>     >
>     > A couple of initial ideas for experimentation:
>     >
>     > 1. Cool the repro head via a small Peltier effect device attached to
>     > it.
>     >
>     > 2. Pre cool the tape by refrigerating it before playing.
>     >
>     > 3. Modify the machine to make the tape run in a small insulated
>     > tunnel, from the exit point on the supply reel to running over  the
>     > repro head, which tunnel could also be cooled via Peltier effect
>     > device. This could also cool the minimum number of tape guides
>     > upstream of the repro head.
>     >
>     > Maybe such work has already been done or at least tried by
>     people such
>     > as Specs Bros? I have no idea.
>     >
>     > Comments?
>     >
>     > Cheers Tim.
>     >
>     > ----- Original Message -----
>     > From: "Association for Recorded Sound Discussion List"
>     > <[log in to unmask] <mailto:[log in to unmask]>>
>     > To:<[log in to unmask] <mailto:[log in to unmask]>>
>     > Cc:
>     > Sent:Thu, 25 Feb 2021 13:33:52 -0500
>     > Subject:Re: [ARSCLIST] Tapes for testing wet play technique
>     >
>     >   Hi, Tim,
>     >
>     >   As you know, Marie's article (with photos) is published on my
>     > website.
>     > 
>      <https://richardhess.com/notes/2006/03/09/wet-playing-of-reel-tapes-with-loss-of-lubricant-a-guest-article-by-marie-oconnell/
>     <https://richardhess.com/notes/2006/03/09/wet-playing-of-reel-tapes-with-loss-of-lubricant-a-guest-article-by-marie-oconnell/>>
>     >
>     >   There is a comparative analysis in my paper from the ARSC Journal.
>     > Not
>     >   much has changed since then and the web page you allude to is
>     meant
>     > as a
>     >   supplement to this paper.
>     > 
>      <http://www.richardhess.com/tape/history/HESS_Tape_Degradation_ARSC_Journal_39-2.pdf
>     <http://www.richardhess.com/tape/history/HESS_Tape_Degradation_ARSC_Journal_39-2.pdf>>
>     >
>     >   For those looking for the supplementary page, it's here.
>     > 
>      <https://richardhess.com/notes/formats/magnetic-media/magnetic-tapes/analog-audio/degrading-tapes/
>     <https://richardhess.com/notes/formats/magnetic-media/magnetic-tapes/analog-audio/degrading-tapes/>>
>     >
>     >   A colleague is doing limited work with PEM-46x and may publish
>     > results
>     >   later. I don't feel able to discuss it in more detail at this
>     point.
>     >
>     >   While I love the initiative demonstrated by Marie's isopropyl drip
>     >   method (which she has indicated she's moved away from), I found
>     > better
>     >   results with decamethylcyclopentasiloxane (D5, cyclomethicone,
>     >   CAS 541-02-6.
>     >
>     >   I just came across this 2008 report on D5 from Environment
>     Canada and
>     >
>     >   Health Canada.
>     > 
>      <https://www.ec.gc.ca/ese-ees/13CC261E-5FB0-4D33-8000-EA6C6440758A/batch2_541-02-6_en.pdf
>     <https://www.ec.gc.ca/ese-ees/13CC261E-5FB0-4D33-8000-EA6C6440758A/batch2_541-02-6_en.pdf>>
>     >
>     >   My degrading tapes page mentions Sony PR-150, but at one point, it
>     > was a
>     >   "poster child" of squealing tape, but later it seems some batches
>     > don't
>     >   show it. I don't mention much about PR-150 as I've expanded so
>     much
>     > on
>     >   other squealing tapes, I should expand on this, too. See if
>     you can
>     > find
>     >   some that squeals.
>     >
>     >   Cheers,
>     >
>     >   Richard
>     >
>     >   On 2021-02-25 12:06 a.m., Tim Gillett wrote:
>     >   > I've revisited playing around with Marie O'Connell's wet play
>     >   > technique but have come to a dead end as I need as a test
>     sample an
>     >   > actual squealing tape which does not respond to normal baking.
>     > Marie
>     >   > mentioned PEM 469 of which I have many reels but the samples
>     I've
>     >   > tried seem to play fine. I also have much 3M 177 but reports on
>     > that
>     >   > seem mixed. Perhaps that's related to the moderate Mediterranean
>     >   > climate here in Perth, Australia.  Richard Hess mentions 3M 175
>     > and
>     >   > some others but what would be the most common known bad cases? I
>     > may
>     >   > have some here in my collection but it would shorten the
>     process if
>     > I
>     >   > could narrow my search down to certain tape types known to
>     squeal
>     >   > regardless of baking.
>     >   >
>     >   > Thanks for any advice,
>     >   >
>     >   > Tim
>     >   >
>     >   > Perth, Western Australia
>     >   > -------------------------
>     >   > Email sent using Optus Webmail
>     >   >
>     >
>     >   --
>     >   Richard L. Hess email: [log in to unmask]
>     <mailto:[log in to unmask]>
>     >   Aurora, Ontario, Canada 647 479 2800
>     > http://www.richardhess.com/tape/contact.htm
>     <http://www.richardhess.com/tape/contact.htm>
>     >   Track Format - Speed - Equalization - Azimuth - Noise Reduction
>     >   Quality tape transfers -- even from hard-to-play tapes.
>     >
>     > -------------------------
>     > Email sent using Optus Webmail
>     >
>
>     -- 
>     Richard L. Hess                   email: [log in to unmask]
>     <mailto:[log in to unmask]>
>     Aurora, Ontario, Canada                             647 479 2800
>     http://www.richardhess.com/tape/contact.htm
>     <http://www.richardhess.com/tape/contact.htm>
>     Track Format - Speed - Equalization - Azimuth - Noise Reduction
>     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
Track Format - Speed - Equalization - Azimuth - Noise Reduction
Quality tape transfers -- even from hard-to-play tapes.