I had to find out about it the hard way, and luckily I didnt ruin my tapes in the process.
Without going into too much detail, sticky shed is what can and usually does happen to your old reel to reel tapes when they start getting older. The problem seems to arise most in the most common of tapes such as the Ampex 456 tape in the years from the early 80s on. Somewhere around this time the government tightened the environmental laws and made it impossible for the tape manufacturers to use certain chemicals to make their tape, so they came up with a new formula, used it widely and it was a few years before they found out that the tapes would not age well. Because of the new formula, the tapes would absorbe moisture and retain it. This would cause the emulsion oxides to separate from the tape, become gummy and flake off... hence sticky shed.
Well unfortunatly for me, and many others the Ampex tapes were pretty popular and I have a boatload of them.
I didnt know what sticky-shed was until I decided to dump the tapes down to my DAW and restore them. I found out really quick when I looped up the first tape and it played about 30 inches and started getting slower and slower and stopped.
Here is the machine... incedentally, for me, this is where it all began - the very same machine that I took my first toke of recording, and became instantly addicted... thats my current recording rig in the background - amazing to see them together. lol
Teac A-2340:
"Well dude, there is nothing wrong with your machine, but I still have to charge you to open it up and look and clean it up.... are you sure your tapes dont have sticky shed?"
BASTARD.
$100 too... and now I find my tapes need to be baked to even play them???
Anyway, so I did some reading up on it, and saw articals where a guys stickyshed problem was cured in the trunk of his car... another made a contraption with a box and a hairdryer.... and thats where I got the idea for my tape baking oven. I had to do it cheap, cuz I was already out $100!
No - I have a GAS OVEN. You cannot bake tapes in a gas oven... they give off too much moisture... thats exactly what you are trying to get rid of... in fact, I wouldnt try it in any kitchen oven... its too hard to keep the temperature steady. See most ovens start at 200F and its really hard to get that temperature to hold steady at the 135F that I needed to bake my tapes. Also, kitchen ovens have no convection, no moving air inside either. You need the moving air to provide the heat and carry the moisture away.
So, before I ramble on too much... as I am known for doing, here is the taping baking recipe for those who are interested.
You need:
- A cardboard box, say about 2'x3'.
A candy thermometer Use candy thermometer because they seem to have an accurate measure of lower cooking temperatures. Most of your oven thermometers really dont register until you hit 180F or more.
- A metal of plastic rack to place your tapes. I used a refridgerator shelf that was laying in the garage... for some reason.
- A small electric space heater. Mine is a GE... dont really need to knwo the wattage or anything.
- a place to set it up. Important. With a space heater running you will clear the house real quick if you decide to do this in the summer. It will get hot.
I cut a 4" x 4" hole in the long end of my box for the heater to blow into, and pierced a small hole in the side to insert the candy thermometer. That simple.
See the following pictures...hehe.. and no, I am not plugging Alesis monitors.. i like mine of course, they serve my needs, and the box came in handy too.
So there it is. The Tape Baking Contraption. You can build one too. Notice where the hole is, and where the candy thermometer goes. The heater goes in the big hole blowing the hot air in.... I had to cover my contraption with a sheet to hold in the heat. The Tape Op Mags and National Geographic combination heat-retainer simple didnt work as well.
Here is the deal.
You need to bake them for 130F - 135F for about 8 hours. Turning and rearranging the tapes once about halfway through.
Test your contraption first to make sure you can keep the heat stable inside.
I had to fool with the heater a lot to get it to hold the temperature and found I had to position the heater a few inches back from the hole to keep it from getting too hot. Try to keep them from going over 140F.
Anything under 125F and the process really isnt occurring. You are driving moisture out with heat, and "galvanizing" the oxide back onto the tape.
When you think you got the temps stable, put your tapes in. Tails in tails out doesnt matter.
Its a slow process, and 8 hours can seem like a long time.
This is what I did while I was waiting:
Yes... I was. What else could I do?? Doesn't everyone bake when they are baking tapes?
So anyway. I had to get up occasionally to check the temperature, and found I had to move the heater around sometimes to keep it constant, but it really wasnt a problem at all. I think, as with anything precious to you as your old archives probably are, its best to keep an eye on them.
1/4" tape: I did 12 full reels at one time. 8 hours. 1/2" tapes may take a while longer, but not too much. It depends on how many you are doing.
Eight hours later. In August, my garage was now 135F. Take the heat away and keep them in the box in a place where it is the lowest humidity you can find in your home. Away from bathrooms, kitchens and windows.... let them cool to room temperature... overnight is probably best.
The best part is when I tried them out the next day. I spooled up the one that played the worst. When I tried it before baking, it would literally only travel a few feet before it would just bind down. Now it played fine... and I swear it sounded better than I had ever heard it before.
I took a journey back to 19 years before when I first started screwing with this recording mess! I had literally not heard any of the material in that long.
You have to work quick, because the tape baking is not a permanent fix. it only lasts about 4 weeks or so, given conditions. The tapes will eventually revert back to their nasty sticky shed forms so its best to get started right away with your transfers.
Not to worry though. If you find you need to roll the tape again in the future, it wont hurt to bake them again and again.
Gotta run and get some rest.
Its pretty simple as you can see... nothing at all too terribly scientific about it.
Feel free to add anything if anyone has other ideas or tricks for this. If you record a lot, this will hit you eventually, you will find yourself needing to roll something really old.
If you never recorded on tape before... well, lets hope we never have to find a fix for digital sticky shed... 01001110101.. thats pretty hard to fix.
Have fun and happy archiving.
Kev
