When I do moldy tapes, I use a NIOSH dual-cartridge respirator.
Don't risk your health.
On 2017-09-27 11:29 PM, Corey Bailey wrote:
> Hi Eli,
>
> Sorry, I didn't see your question about the "Soaking". I had a tape
> similar to your problem tape and here's what I did: I used a round film
> can and (literally) submerged the 7" reel of tape in medical alcoholfor
> about an hour. You can submerge the tape for longer if you think it
> needs it because (IMHO) pure alcohol does not harm PVC base audio tape.
> Others may differ. After the "Soaking", I unwound the tape, slowly, by
> hand, while wiping with pellon. Much the same as you describe except I
> use a modified 8MM film editor for this task. I had to replace every
> leader on this particular tape and there were lots of them. Mold is
> serious business. Much of it is microscopic and the spores get
> everywhere. If you are indoors, you need a "clean room" that is isolated
> from everything else. I set up outside, away from anything that may be
> subject to mold contamination. Only after I was confident that I had
> conquered the mold contamination, did I consider baking the tape. In
> this case, the tape did not need to be baked. The tape (Again, IMHO) was
> Scotch 206 and played fine after restoration*. * Restoration included
> lubricating the entire tape...Another topic for another time.
>
> Corey
>
> Corey Bailey Audio Engineering
> www.baileyzone.net
>
> On 9/27/2017 1:27 PM, Eli Bildirici wrote:
>> Shai wrote:
>>
>> "The bleed through could also be print through. It actually doesn't
>> look as
>> bad as I thought. I would start with a low temp bake (about 40
>> Celsius) for
>> 24-48 hours.Next I would try to unspool and clean a short length of
>> tape to
>> see if any flaking occurs. If not I would clean the rest of the tape and
>> try to play. If it still give trouble I would rebake for antoher 24 hours
>> at 55 Celsius."
>>
>> Thanks. What we've had to do however, as nearly all of our content
>> left to digitize and catalogue
>> are on 7" reels, is first transfer them onto a 10" one, as that's what
>> fits in our dehydrator:
>>
>> https://imgur.com/sCyrUqK
>>
>> I'm realizing based on these comments though that this is far from
>> ideal (and follows logically, at that), so if anybody has advice as to
>> particular models of dehydrators that can accommodate reels of this
>> size, I'm all ears.
>>
>>
>> Corey - can you elaborate on the 'soaking' process? What we've been
>> doing until now is using a dedicated R2R solely for cleaning, playing
>> through a tape while holding a bit of Pellon with some 99% isopropyl
>> alcohol against it as it spools. Soaking it without unspooling is of
>> course very different - how long do you think? How deep? Should it go
>> straight from having been soaked (ideally) into the dehydrator?
>>
>> Would you guys propose checking the tape whilst it's being baked every
>> 24 hours?
>>
>> Increasingly, many of our reels left to process appear to have a bunch
>> of different, unrelated segments strewn together, sometimes in the
>> wrong direction and rarely with any kind of indication as to what's on
>> there. Often if not always, if leader is used to separate the segments
>> at all, it is paper. In case there is no mold, but the tapes are
>> shedding, should
>>
>> I looked at Richard Hess's site yesterday and found this reference:
>> http://richardhess.com/notes/formats/magnetic-media/magnetic-tapes/analog-audio/degrading-tapes/
>>
>> I don't think there's a way to identify tape stock by sight though, so
>> it looks like this doesn't help me much. I've been going through the
>> Specs site, meanwhile. Among the more interesting things is the
>> implication that this white residue I'm seeing...isn't actually mold?
>> But instead may "indicate breakdown of various chemical components":
>>
>> http://www.specsbros.com/white-paper-basic-inspection-techniques-to-sample-the-condition-of-magnetic-tape.html
>>
>>
>> I'm not sure what, if any, ramifications this could have.
>>
>> E
>>
>> September 27 2017 2:53 PM, "Corey Bailey" <[log in to unmask]>
>> wrote:
>>
>>> Hi Eli,
>>>
>>> You have a host of problems with this reel of tape (preaching to the
>>> choir here): Mold, Shedding
>>> which may require some baking, and segments separated by paper
>>> leader. Paper leader is not bad by
>>> itself but, in this case, it's adding to the problem because of mold
>>> and moisture absorption.
>>>
>>> 1) Address the mold. Baking a moldy tape will contaminate your oven.
>>> Avoid (if you can) any water
>>> based mold killing products. Pure alcohol work well as a first or
>>> second application. Soaking the
>>> tape with alcohol may reduce the sticky layer problem to the point
>>> that it can be carefully unwound
>>> to move on to step 2.
>>>
>>> 2) Replace the paper leader with plastic leader. I've also used blank
>>> Polyester tape (reversed) as
>>> leader. Then, continue with mold removal because you want to remove
>>> ALL of the mold.
>>>
>>> 3) Bake the tape if you think it is safe to do so. Bake looow (Temp)
>>> and sloow: Less than 49C
>>> (120F) for as long as it takes. 24 to 48 hours would not be uncommon.
>>> I would suggest using a
>>> dehydrator for this particular application or, any unit that you can
>>> safely dispose of because
>>> contamination may be unavoidable, rendering the baking device
>>> unusable for anything else.
>>>
>>> Check with Peter Brothers to see if Specs Bros. may have some advice:
>>> http://www.specsbros.com
>>>
>>> You may have to decide which is more important: Saving the tape or
>>> saving the equipment. Corporate
>>> America, in my experience, would decide that the process is too
>>> expensive and chuck the tape.
>>>
>>> Advise is free so, contact me off-list if you like.
>>>
>>> Sorry,
>>>
>>> Corey
>>>
>>> Corey Bailey Audio Engineering
>>> www.baileyzone.net
>>>
>>> On 9/26/2017 1:56 PM, Eli Bildirici wrote:
>>>
>>>> We all just double-checked and it looks like polyester rather than
>>>> acetate. My guess is the angle
>>>> of my phone and the way the sunlight was hitting the tape made it
>>>> look wrong. Do you have any
>>>> advice re baking?
>>>>
>>>> September 26 2017 4:27 PM, "John Chester" <[log in to unmask]> wrote:
>>> On 9/26/17 4:10 PM, Ted Kendall wrote:
>>>> If you are getting what I think you mean by bleedthrough, bits of >
>>>> oxide have already lifted and
>>>> stuck to the back of adjacent turns. If > you have played it, it's
>>>> probably too late to do much,
>>>> but you could > start by baking and see what can be salvaged.
>>> The loose end of the tape which I see in the photos is red oxide with
>>> no backcoating. Tapes
>>> without backcoating rarely need to be baked. If any of the tape on
>>> this reel is acetate base, it
>>> should absolutely not be baked. To check for acetate base, hold the
>>> reel up to a light -- if you
>>> can see light through the tape pack, it's acetate.
>>>
>>> The nightmare scenario is a mixed reel that's got sticky-shed tape on
>>> the outside, and acetate tape
>>> further into the reel. In that case, you pretty much have to decide
>>> which you will save, because
>>> you probably can't save both. Baking will ruin the acetate, and
>>> unspooling the sticky-shed tape
>>> without baking may leave large chunks of oxide stuck to the backcoating.
>>>
>>> -- John Chester
>> Eli Bildirici
>> (347) 837-8337
>
--
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.
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