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My experience with baked 456 and 407 tapes has been that the little shreds Curtis is describing do 
sometimes happen and I agree with Richard as to the cause. On my Ampex AG-440B, I looked carefully 
at what was happening and I think the tape gets into some bad "country lane-ing" because it probably 
wasn't slit very well and the process of sticky-shed and baking seems to make it less "square" (or 
"rectangular") by a small amount. Who knows why. Those old 456 tapes are just plain bad news. My 
stock advice is -- bake it once, make a really good transfer (excellent playback, excellent ADC, 
high resolution digital file) and then figure that's about as good as you're going to do. Unless 
it's the master tape for "Dark Side of the Moon" or something equally famous, that's probably 
enough. Keep the tape, of course, but use your resources for other things once you get it to 
playback well.

-- Tom Fine

----- Original Message ----- 
From: "Richard L. Hess" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, April 01, 2013 12:40 PM
Subject: Re: [ARSCLIST] Sticky SHRED


> Hi, Curtis,
>
> I've been baking longer, but edge shedding as you describe is common if the tape is slit a bit 
> wide (hard to measure, but that is why the event is so random--it might be one reel out of a jumbo 
> roll where the slitting blades were mis-adjusted).
>
> I don't think 24 hours (my norm these days) would show a difference as I saw this off some 
> 1/2-inch 456 just recently, but it was only the edge.
>
> It is frightening, but I'd just vacuum up the little hairs and be done with it. Remember, those 
> are about a mil wide and you're dealing with nominally 82-mil (minimum spec'd is 75 mil from 
> Ampex) track width that doesn't even go completely to the edge, so you probably don't have any 
> sound on the little hairs. (I did want to write "hares" in honour of the season. <smile>)
>
> I would check for debris in the corners of the guides (where the face meets the top and bottom 
> caps) which can exacerbate this hair-shred but, overall, if it's coming just from the edges, I 
> think you're safe.
>
> I see 456 doing this more (though I've seen it more on 1/2-inch than 1/4-inch). It has also 
> happened on Agfa and BASF, but not regularly.
>
> I don't have this variant specifically listed, but you might find this resource of use:
> http://richardhess.com/notes/formats/magnetic-media/magnetic-tapes/analog-audio/degrading-tapes/
>
> Good luck!
>
> Cheers,
>
> Richard
>
> On 2013-04-01 12:10 PM, Peoples, Curtis wrote:
>> Hi Richard,
>>
>> I believe the tape is Ampex 456, not positive though. The studio generally bought Ampex 456 tape. 
>> It is a ten inch, quarter inch reel (two track master recording). For this collection, we bake 8 
>> hours at 130 degrees. We have found this to be a suitable process for this collection.  The 
>> shredding appears to be from the edges. We are transferring on a relatively new Otari MX 5050. 
>> The machine was cleaned so I don't have pics of the shred. They are usually about 3 inches long 
>> before breaking and are about the thickness of fine hair.
>>
>> Best,
>>
>> Curtis
>>
>> -----Original Message-----
>> From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf 
>> Of Richard L. Hess
>> Sent: Monday, April 01, 2013 10:48 AM
>> To: [log in to unmask]
>> Subject: Re: [ARSCLIST] Sticky SHRED
>>
>> Hi, Curtis,
>>
>> Please provide specifics as to type of tape, width, reel type, baking process and duration.
>>
>> Also photographs are really useful.
>>
>> Is the shredding from the edges only or across the entire width of the tape?
>>
>> What is the playback machine?
>>
>> Cheers,
>>
>> Richard
>>
>> On 2013-04-01 10:35 AM, Peoples, Curtis wrote:
>>> Hi Folks,
>>>
>>> We have a collection of tapes that have sticky shed and we are baking and transferring them. 
>>> Things are going as planned except for one tape. It is shredding into fine hair like stands. I 
>>> thought it needed to be baked longer so I baked it a second time. Same problem. I have seen tape 
>>> shed before and this looks different.
>>>
>>> Any help identifying the problem is greatly appreciated.
>>>
>>> Best,
>>>
>>> Curtis L. Peoples, Ph.D.
>>> Associate Archivist, Crossroads Music Archive,
>>> www.crossroadsofmusic.ttu.edu<http://www.crossroadsofmusic.ttu.edu/>
>>> Unit Head, Crossroads Recording Studio,
>>> http://library.ttu.edu/crossroadsrecordingstudio/
>>> Director, TTU Americana Ensemble,
>>> http://ttuamericanaensemble.weebly.com/index.html
>>>
>>> Contact Info:
>>> Southwest Collection, Texas Tech University P. O. Box 41041 Lubbock,
>>> Texas 79409-1041
>>> Email: [log in to unmask]
>>> TEL: 806-742-3749 ext. 278
>>> FAX: 806-742-0496
>>>
>
> -- 
> 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.
>