One correction -- Scotch 150 is actually polyester-backed. 111 and 190 are acetate. I just noticed 
that one of the 150 reels is virgin, so I plan to test it like I tested the Maxell and Columbia 
tapes, see how it behaves with sine waves.

-- Tom Fine

----- Original Message ----- 
From: "Tom Fine" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, January 31, 2016 8:46 AM
Subject: Re: [ARSCLIST] Baking times for Ampex 456 increasing? How Much? Why?


> Hi John,
>
> Yes, the recommended storage for back-coated tapes (since many of them seem to have SSS problems) 
> is cold and dry. My contention, which I stand by having dealt with MANY acetate-backed tapes, 
> including tapes stored under such conditions, is that this is not optimal for acetate, that 
> acetate tapes don't want it dry (cold seems to be fine in either case, probably better for both, 
> especially if it's a cold and mold-free environment). Polyester non-back-coated tapes seem not to 
> care, in fact many of these types seem to be the most durable (although we've had reports from 
> Richard and others of polyester/no-back-coat types that get a very insidious kind of stiction 
> problem, requiring slow playback under very cold conditions or constant lubrication through the 
> playback cycle).
>
> My experience, owning many acetate-backed tapes for many years, and those tapes always having been 
> stored in ambient NY indoors condition, is that they want it relatively cool (ie not on the top 
> shelves of a non-air-conditioned room, or yeas in an attic) and more humid (but not humid enough 
> for mold to grow), and then they don't get wrinkled, edge-curled, etc. I haven't had too many 
> develop vinegar syndrome, because most of them are Audiotape (the only tape brands I've had 
> develop vinegar syndrome are acetate-backed Kodak [all tapes I've ever had hands on], Scotch 111 
> [only a few reels out of many I've had hands on], and Reeves Soundcraft [about half of the few 
> reels I've had hands on]).
>
> I keep saying that more research should be done whether it's really a good idea to store acetate 
> and polyester tapes under the same vault conditions. I also keep saying that I haven't seen any 
> science showing that dry conditions have any effect on staving off SSS or prolonging playability 
> of treated tapes. So my contention has been, until it's proven that very-dry conditions actually 
> benefit polyester tapes, I wouldn't keep it so dry as to damage acetate tapes, if both types are 
> in the same vault. Also, as a general rule, were I in charge of a vault, I would make it a 
> priority to do very high quality transfers of my acetate tapes because they are by now ancient in 
> almost all cases and it's unreasonably optimistic to think they will remain playable indefinitely.
>
> By the way, recent datapoint. I just went through about 30 yard-sale tapes, about half of them 
> Scotch and Audiotape acetate-backed. I found a receipt for some of the Audiotape reels, indicating 
> they were bought in the Cleveland area, so I'm guessing they migrated from the Midwest to middle 
> NJ and spent most or all of their time in ambient environments. None of the Audiotape reels are 
> warped, curled or vinegary. One Scotch 111 reel was badly warped and curled, but none of the 
> thinner Scotch 150 and Scoth 190 were warped or curled. Go figure! All of the Scotch tape was from 
> that era where the 3M company orchestra is pictured on the box, I think that's mid-50's. The 
> Audiotape packaging and the sales receipt indicated same time period. All of those were half-track 
> 7.5IPS and 3.75IPS amateur recordings of LP records, and not all that good quality. It's worth 
> saying that all of the acetate tapes were somewhat brittle (ie they snapped pretty easily when 
> bent or pulled). The same person (based on the box handwriting) must have taken a long break from 
> reel tapes and then got back into it in the 70s. In that batch, we have sticky Ampex 407, a few 
> reels of Columbia-branded tape, which I assume was made in the old Reeves Soundcraft plant in 
> Danbury CT, and early Maxell UD tape. The Maxell and Columbia tapes are in fine shape. Since I 
> didn't like any of the music on them, I tested one of each on one of my Technics 1520 machines, 
> which have front-panel recording bias and EQ. Using an external oscillator and watching the phase 
> on a scope, I found both tapes to be mechanically stable and able to set up with rock-solid meter 
> readings (meaning the tape wasn't screwed up so the bias was effecting every next bit differently 
> from the previous bit -- I've seen this with very old and very damaged Scotch 206 tape and 
> definitely with old acetate tape, which may have not been going through the transport smoothly 
> with that low tension around the heads). The Maxell tape, in particular, was well preserved; the 
> guy had kept it in its plastic bags within the boxes. The bags smelled a little bit and were 
> somewhat "greasy," so I threw them out and replaced the tape boxes as well.
>
> -- Tom Fine
>
> ----- Original Message ----- 
> From: "John Haley" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, January 31, 2016 12:57 AM
> Subject: Re: [ARSCLIST] Baking times for Ampex 456 increasing? How Much? Why?
>
>
>> Since the culprit for SS is hydrolysis, which results from the addition of
>> moisture, and we bake a tape to desiccate it, shouldn't we assume that
>> moist storage is bad for tapes that get SS, and dry storage is good, as a
>> general proposition?
>>
>> How about temperature extremes?
>>
>> My experience is that for most tapes made prior to the SS era, tapes are
>> not that picky about storage conditions, within reason.  I.e., in general,
>> they seem to have held up well through a big variety of storage conditions.
>>
>>
>> This discussion has dealt largely with troubled tapes.  What are the
>> lessons learned applicable for regular tapes, if any?
>>
>> Thanks,
>> John Haley
>>
>>
>> On Sat, Jan 30, 2016 at 10:09 PM, Richard L. Hess <[log in to unmask]>
>> wrote:
>>
>>> Hi, Tom,
>>>
>>> Steve Smolian's comment makes me think it doesn't have to be a separate
>>> plant, but perhaps a separate formula? Of course, shipping as discussed
>>> does come into play.
>>>
>>> I wonder what the different climates are that Marie's tapes have been
>>> stored in...
>>>
>>> I know many of the tapes I receive from Canada have been stored in very
>>> humid locations. I rescued some tapes from a Toronto basement sixteen years
>>> ago or so where I practically slipped on my rear in the slick mud on the
>>> floor. My wife's office is in an old house where the basement gets wet with
>>> each rain. It's an historic old house and she works for the Historical
>>> Society that owns it.
>>>
>>> Cheers,
>>>
>>> Richard
>>>
>>>
>>> On 1/29/2016 3:52 PM, Tom Fine wrote:
>>> ...>
>>>
>>>> Richard, your theory about different formulas for Commonwealth
>>>> Ampex-branded tapes may well be true, but you'd need to suss out for
>>>> sure where all that tape was manufactured. I'm not aware of any Ampex
>>>> plant except Opelika AL (formerly Orradio Industries). For that matter,
>>>> did 3M have tape-making plants other than in Minnesota? I always thought
>>>> that Ampex and 3M tapes were made in USA; Sony, Maxell, TDK and maybe
>>>> Memorex were made in Japan; BASF was made in Germany and Agfa was made
>>>> in Germany and Holland. As I understand it, there was a Russian tape
>>>> manufacturer in the Cold War era, but Soviet and Eastern Bloc recordists
>>>> also bought a lot of Agfa and BASF tape.
>>>>
>>>>
>>> --
>>> 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.
>>>
>>
>>
>
>