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Thanks Corey and Richard,

For the tapes(s) that wont separate without damage I'll try the heating as 
well as the chilling technique and report back.

Tim.



----- Original Message ----- 
From: "Richard L. Hess" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, October 17, 2018 8:08 AM
Subject: Re: [ARSCLIST] Soundmirror paper 1/4" tape


> Hi, Tim,
>
> The only thought I had is that there was moisture intrusion into the tape 
> pack at some point to cause this. This could have been moisture on its own 
> or with biological or chemical contaminants that acted like an adhesive or 
> caused the tape coatings to act like an adhesive.
>
> It is just a guess with no real science to back it up.
>
> Yes, I would try baking to separate, but that's not always useful, either.
>
> The other thing that has occasionally worked with blocked tapes is 
> chilling them for a while, both to drive out moisture and get some 
> micro-movement layer to layer which may "unhook" the little bonds.
>
> If you hear a zipper noise, you are damaging tape.
>
> Good Luck!
>
> Richard
>
>
>
>
> On 2018-10-16 4:58 PM, Tim Gillett wrote:
>> Hi Corey,
>>
>> No, definitely not normal sticky shed or even any stickiness.
>>
>> My tentative guess is that with time and pressure the rough surface of 
>> the paper backing has imprinted itself onto the adjacent layer's smoother 
>> oxide surface so that many tiny "interlock" or clasp points have formed. 
>> On the sections where the winds have separated without damage, the 
>> interlocks have released and now there is no longer a stiction in those 
>> sections. I can rewind the tape back from where the tape stopped and it 
>> winds perfectly. No stiction. For a paper tape, the pack is quite good. 
>> When I run the tape forward, as soon as it gets to the point where I 
>> stopped separating the wind, the adhesion resumes.
>>
>> It's complicated by various sticky tape splices which have gone gooey and 
>> oozed, causing adhesions at those points but that's a separate issue.
>>
>> Yes there are unrecorded sections which I can experiment with.
>>
>> Thanks,
>> Tim
>>
>>
>> ----- Original Message ----- From: "Corey Bailey" 
>> <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Wednesday, October 17, 2018 4:12 AM
>> Subject: Re: [ARSCLIST] Soundmirror paper 1/4" tape
>>
>>
>>> Hi Tim,
>>>
>>> It's hard to recommend a solution without visually assessing the 
>>> problem. For polyester base tapes that have layer-to-layer adhesion, I 
>>> usually have to bake them at a lowered temperature (118° F. or less) for 
>>> 6 to 8 hours and then I will check the tape again. For paper backed 
>>> tape, baking may not work. Is there an unrecorded section that you could 
>>> use for testing? For me, baking audio tape is reserved as a last resort. 
>>> Layer-to-layer adhesion is the one exception.
>>>
>>> Cheers!
>>>
>>> Corey
>>>
>>> Corey Bailey Audio Engineering
>>> www.baileyzone.net
>>>
>>> On 10/16/2018 6:11 AM, Tim Gillett wrote:
>>>> Thanks Gary,
>>>>
>>>> Yes having had experience with one tape like this 15 years ago (from 
>>>> the same person's archive) I'm aware of the centre track, the tracks 2 
>>>> and 3 capture and the azimuth corrector technique. It's just a shame I 
>>>> wasnt aware of this sticking problem back then as I guess if I'd 
>>>> unwound them then it wouldnt have been as much of a problem as has now 
>>>> become 15 years on.
>>>>
>>>> I only recently discovered that the tapes have been stored in less than 
>>>> ideal conditions with high humidity and evidence of mould on some tapes 
>>>> (but apparently not on any of these Soundmirror tapes that I can see.
>>>>
>>>> Yes hoping Richard Hess or maybe Peter Brothers might have experience 
>>>> with this sticky problem.
>>>>
>>>> Regards,
>>>>
>>>> Tim.
>>>>
>>>>
>>>> ----- Original Message ----- From: "Gary A. Galo" <[log in to unmask]>
>>>> To: <[log in to unmask]>
>>>> Sent: Tuesday, October 16, 2018 8:57 PM
>>>> Subject: Re: [ARSCLIST] Soundmirror paper 1/4" tape
>>>>
>>>>
>>>> Hi Tim,
>>>>
>>>> This is a strange problem. I've worked with quite a few Brush 
>>>> Soundmirror tapes in our archive, and the only spots where I found any 
>>>> sticking was on a couple that had leader tape spliced on at the 
>>>> beginning. But, it was confined to that spot, and not all the way 
>>>> through.
>>>>
>>>> Regarding playback on modern equipment, I use tracks 2 and 3 of a 
>>>> 4-channel head. They fit right over that single half track on the 
>>>> Soundmirror tapes. The stereo playback allows proper azimuth 
>>>> adjustment, and gets you inside of most of the edge curl that may have 
>>>> occurred. It may also get you inside any oxide shedding that may 
>>>> happen, if that stickiness is confined to the edges. Then I put the two 
>>>> channels through a phase corrector before summing them to mono.
>>>>
>>>> Richard Hess may be able to better address the sticking problem.
>>>>
>>>> Best
>>>> Gary
>>>>
>>>> Gary Galo
>>>> Audio Engineer Emeritus
>>>> The Crane School of Music
>>>> SUNY at Potsdam, NY 13676
>>>>
>>>> ________________________________
>>>> From: Association for Recorded Sound Discussion List 
>>>> <[log in to unmask]> on behalf of Tim Gillett 
>>>> <[log in to unmask]>
>>>> Sent: Tuesday, October 16, 2018 8:32:39 AM
>>>> To: [log in to unmask]
>>>> Subject: [ARSCLIST] Soundmirror paper 1/4" tape
>>>>
>>>> Hello,
>>>>
>>>> I'm having problems with some very early Soundmirror tapes using a 
>>>> paper backing, circa late 40's early fifties I guess. I suspect they 
>>>> havent been wound or played for many decades. They contain live 
>>>> recordings of mainly classical oratorio concerts.
>>>>
>>>> The tape wind is semi sticking to the next wind in varying degrees 
>>>> depending on the tape in question. With a couple I've been able to 
>>>> slowly wind them off without tape breakage or loss of oxide. Once they 
>>>> have been unstuck and spooled onto the take up reel they remain unstuck 
>>>> and play well. I've been able to repair old splices and clean off old 
>>>> spreading adhesive.
>>>>
>>>> But this one is more sticky and further into the reel I go it has 
>>>> started to really stick to the next wind and rip off small pieces of 
>>>> oxide (I guess more tension from being under a constant torque wind for 
>>>> many years has made the inner layers stick more to each other).
>>>>
>>>> Any hints on treating the tape to help it wind off without damage, or 
>>>> with less damage? Heat, humidity etc?
>>>>
>>>> Thanks,
>>>>
>>>> Tim Gillett
>>>> Perth,
>>>> Western Australia
>>
>>
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> -- 
> 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.