Print

Print


Very interesting! Thanks for informing me. I have been immersed in film for
the past few years.... developed a new machine.
www.filmictech.com

one of the things being worked on is a new tape cleaner - reel to reel from
1/4" to 2" using pellon. not tomorrow but probably less then a year out.
the transport is the same as the film system and that was the really hard
part.

I dont know if you got my email thanking you for your annual Christmas
Update. I do read and enjoy them!
regards to all
jim


On Fri, Feb 26, 2021 at 6:07 PM Richard L. Hess <[log in to unmask]>
wrote:

> 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
>
> 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
>
>
>  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]>
> 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/
>>     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]>
>> > To:<[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/
>> >
>> >
>> >   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
>> >
>> >
>> >   For those looking for the supplementary page, it's here.
>> >   <
>> 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
>> >
>> >
>> >   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]
>> >   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.
>> >
>> > -------------------------
>> > Email sent using Optus Webmail
>> >
>>
>> --
>> 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.
>>
> --
> Richard L. Hess                   email: [log in to unmask]
> Aurora, Ontario, Canada                             647 479 2800http://www.richardhess.com/tape/contact.htm
> Track Format - Speed - Equalization - Azimuth - Noise Reduction
> Quality tape transfers -- even from hard-to-play tapes.
>
>