You mean the pinch roller - not the captsan- I have some of the stuff somewhere from my TEAC 4-track - but I would not use chemical directly on the pinch roller any more than necessary - blasts from the compressed computer cleaner variety is better - keep all liquid out of the capstan bearing as you know.

If the tape is spooling off sticky and causing high-tension on the take-up - oww! best to pull it off. We use to use set of 16mm editing table moviola rewinds to exercise the tape first.

ITGuy,

yeah the pinch roller. I am a video guy so audio terminology does not flow off my tongue.

The sticky tapes we are going to send to be processed by a recovery company that dries them out in some way. These tapes are just primarily shedding rust.

Dave T2

As you said, its a rubber part so avoid alcohol as that would rot it.
I used to use a weak solution of washing up liquid and water. Using a cotton bud with the transport running, clean the brown/black dirt off the rubber pitch wheel.
Allow to dry, should be fine.

if its really bad and riding the tape up or down (sometimes leading to tape chewing) you may need a new pinch wheel.

Clean heads with isopropyl alcohol and cotton buds.
Maybe de-mag the heads with de-mag wand if possible.

Paul.

Trichlorethylene is what we used for both tape and film transports. OK on rubber and neoprene. Our plants were so big they'd ship it in 50 gal. drums. Don't let it come in contact with skin and use in a well ventilated area. It used to be used as a general anesthetic (chloroform).
May still be available at Ace or True Value (can't remember which) under the name "Carbo Chlor."
Don't use anything containing perchlorethylene, it's even worse.

I've seen tricks online to keep the oxide on the base. Can't give you firsthand information on that; I bet John Meyer can, however.

I think after tranferring all of these tapes, I will fill like I have taken some chloroform. Thanks for the feedback.

Dave T2

Paul,

I was using denatured alcohol on the heads. The pinch roller is relatively clean right now, but I know I have some tapes that are really deteriorating.

Thanks
Dave T2

Musicvid,

Like I said, the tapes that are too sticky to pull thru are going to a service that uses a process to "dry" them out. So I won't be dealing with fixing them myself.
THanks
Dave T2

Yeah, should be fine.

Old tapes will always loose oxide through the transport. Just gotta keep everything in the path as clean as you can! Clean after every tape pass. Good luck with the tape drying process - that should help.

Paul.

"Hey, I am doing a major archive project which involves transferring hours of 1/4" audio, most of which dates from 1983 forward. As you may have guessed, the tape is shedding bad so I have to clean the heads often. I am using denatured alcohol for that, but any suggestions on what to clean the rubber capstan with? I know not to use alcohol, so what should I use?"

First of all if the tapes are shedding a lot then they almost certainly are suffering from "sticky shed syndrome" and you should not even attempt to play or spool them until that is dealt with. All that oxide coming off the tape is what contains the information you're trying to recover.

The tapes need to be baked at 51 deg C for two hours in dry air. I've built two ovens specifically for that purpose, we discovered that adding a dessicant to the oven significantly improved the outcome. If you need any details PM me.

If you send the tapes to someone else to dry them out keep in mind you have around 2 weeks before they tape binder may absorb moisture again and become sticky. On the upside it seems the drying process can be repeated without doing harm. Never had to do this myself as it was always straight from the oven onto the deck. We still have an Otari 5050.

"It is an Otari MTR-12 in case that means anything to you"

That's a very good deck as it has rolling guides so the tape will be well treated. You can use the decks with rolling guides to spool tape with sticky shed with safety.


We just used Propanol to clean the heads and pinch rollers. Note that some rubber formulations from way back can suddenly turn to chewing gum, watch out for this, has nothing to do with how you clean the rollers. If you need new pinch rollers I've had a guy in the USA make new ones for our 5050. Not that expensive and the new rubber formulations don't turn to goo.


Other thing to watch out for is many tapes from back then used various systems of companding such as Dolby SR. I have two stereo Dolby SR encoder / decoder units. If you need one let me know. They're not all that heavy and one of mine was only $100 to transport from the USA. Last time I checked there was one new unit left in the UK going for $7K. You can tell if the tapes were recorded with SR by the alignment tones at the start, you'll get bursts of what sounds like pink noise which is used to align the SR decoder.

Bob.

For excessive shedding the tapes should be baked. We used to clean the rubber pinch rollers with 409 household cleaner and apply Scotty's rubber cleaner/conditioner as well. We'd use EverClear grain alcohol for the capstan, heads and other metal tape path parts. After stressful sessions we would drink the EverClear.

Like Bob (farss) said, DO NOT PLAY the tapes until you bake them. Most audio tape from the 70s and early 80s has this problem, particularly Ampex 456 and Scotch. Google "tape baking", it's somewhat critical to regulate the temperature, it's not something you can do with a toaster oven.

Some interesting reading while you're sitting watching analog meters. If I knew you were coming, I'd have baked a tape...

When I worked for IBM, we could order edit: 1,1,1-Trichloroethylene (Gold Can Cleaner) by the case. I think that's what's wrong with me.

Also be aware if the tapes are Ampex and shedding a white powder - this is Lead Oxide (some form of lead was used as a lubricant in the coating when Whale Oil was banned) - therefore do not ingest or breathe in, and wash hands meticulously after touching.
We found Ampex recorders with Ferrite Heads played these tapes OK after baking, but Studer heads could be damaged by the lead oxide.

I have come accross another solution to the sticky shed problem, silicon oil.
The concept is to apply an extremely thin layer over the tape so it slides over the heads and quides. The source of the silicon is nothing more than Mr Sheen. A felt pad is used to apply some as it comes off the reel.

I have only tried this once and with a tape I was having a lot of issues with and it did work a treat. What had happened to this tape was more than just it being sticky. It had been wound too tight prior to storage and the binder had been extruded out the edges of the tape. After baking the tape was jamming in the guides and the silicon from the Mr Sheen was enough to get the tape to stay in the guides.


One startling discovery we made after we'd pretty much done with the business of recovering content off 1/4" tape was that a considerable amount of video tape also suffered from this problem. What a quad head does to 2" tape with sticky shed is quite spectacular, all the oxide is just ripped off. We've also found 1" tape and UMatic tape with sticky shed. Fungal growth is also an issue and baking also helps to dry it out and then it'll come off the tape as it's spooled and played. Still a lot of head, roller and guide cleaning required though.

Bob.

... and when you 'bake' them, don't use an oven. Best is a food dehydrator, which often have round trays just right for a spool, and can be reliably set to the necessary stable 50 degrees (C).

geoff

Wow, so much knowledge and good advice, I can't respond to you all so I hope you all get to read this.
Thanks again, I knew this was the place to ask. I will not be attempting to dry the tapes. I would end up having charcoal I am sure. We are sending them to a place that specializes in this for audio and video tape. That way if it goes wrong, it is out of my hands. We have several hours and most of the tape is okay, just shedding some, but 2 or 3 reels will not pull through the deck. We have some VHS's with the same issue, but I don't know how much of that they are archiving.

Again, thanks for being willing to offer your advice and wisdom. It is not wasted.

Dave T2

Just one of those "wrap my head around this" moments ... the shedding should all be on the magnetic side, which on almost ALL reel tape decks is the side that touches the heads and the metal capstan. The side that touches the rubber pinch roller should should be a) relatively free from the shed material, and b) relatively unaffected even if it does accumulate the gunk. It's the capstan that regulates the speed, not the pinch roller. So, thorough cleaning of the pinch roller is probably unnecessary; just brush off any large globs that might appear.

Of course, there are some decks that swap the sides of the capstan and pinch roller, and there are some decks that use rubber capstans (Technics was famous for this, especially for wider tape). I don't think this applies to Otari or Studer though.

Chienworks,

On this one the rubber pinch roller is on the oxide side. I have already wiped it with a cloth a few times, and got some dust off. I say rubber, but I don't know exactly what material it is. There is a rubber one on the feed side, but that is not pinched and I think it is the tach for tape placement for cueing and such. that one is on the outside of the tape.

I have had to clean the capstan a couple of times too though even though it presses the outside.

Dave T2

Just a general note on the rollers:

Almost any of the alcohols will dry the rubber and remove the phenylinediamines that are are added as preservatives. End result: drying, shrinkage, cracking, and glazing of the rubber compounds.

Also, denatured alcohol always leaves a film or residue. Not good on capstans.

Thanks, did not know that. I will check and see if it is denatured or isopropyl that we are using.

Dave T2

I used Tascam Rubber Cleaner on pinch rollers for decades, it worked great but they stopped making it a long time ago. I've been using CaiKleen™ RBR and it works every bit as well.

http://store.caig.com/s.nl/sc.2/category.179/.f

Yes John Cline, the Tascam cleaner was TCE, iirc. Check local hardware stores for "Carbo Chlor." Same stuff, I'm almost sure. The differences between Trichlorethylene and Trichloethane were pretty much inconsequential for industrial uses. The safety precautions for each are nearly identical -- avoid skin and eye contact, avoid inhalation, use forced ventilation, lest you be rendered a blithering idiot.