Is this a sign of sticky shed on 3M 996?

N

N7SC

New member
Here is the problem: I bought a case of 12 pancakes of new-old-stock 3M 996 tape. These are 2500' rolls of 1/4 inch tape on NAB hubs only, no flanges. The batch in question bears date codes indicating it was made in 1991. I just started winding it on to Polyline plastic reels by screwing flanges from a spare NAB reel to the hubs then running it through my Revox A77 on to the Polyline reel at 15 ips. Toward the end of each of the three pancakes/reels I've wound so far, it starts squealing intermittently. I can silence it by spinning the supply reel by hand, a bit faster than it is unwinding on its own. Kind of pre-releasing the tape.

Also have noted lotsa krud build up on the erase head (first one the tape touches) after each reel is run through. Cleaned it completely between each reel. Thing is that there is not only the oxide-looking gunk you'd expect, but some long white threads too. Looks really weird.

I thought that the 3M 900 series tapes did not suffer from sticky-shed. In fact all my other 996 doesn't do this at all - it is trouble free and great tape. Could this be just from being left tightly wound on the hubs for so long. And could I maybe clean it up some how and get it past its problems, or am I doomed with what appears to be a case of shedding 996?
 
N7SC said:
Here is the problem: I bought a case of 12 pancakes of new-old-stock 3M 996 tape. These are 2500' rolls of 1/4 inch tape on NAB hubs only, no flanges. The batch in question bears date codes indicating it was made in 1991. I just started winding it on to Polyline plastic reels by screwing flanges from a spare NAB reel to the hubs then running it through my Revox A77 on to the Polyline reel at 15 ips. Toward the end of each of the three pancakes/reels I've wound so far, it starts squealing intermittently. I can silence it by spinning the supply reel by hand, a bit faster than it is unwinding on its own. Kind of pre-releasing the tape.

Also have noted lotsa krud build up on the erase head (first one the tape touches) after each reel is run through. Cleaned it completely between each reel. Thing is that there is not only the oxide-looking gunk you'd expect, but some long white threads too. Looks really weird.

I thought that the 3M 900 series tapes did not suffer from sticky-shed. In fact all my other 996 doesn't do this at all - it is trouble free and great tape. Could this be just from being left tightly wound on the hubs for so long. And could I maybe clean it up some how and get it past its problems, or am I doomed with what appears to be a case of shedding 996?
Click to expand...

You have the STS. Get a shot fast before you infect anyone else. Get rid of that tape if you value your machines. Getting cheap and baking will only lengthen the demise of your machines.


Don't say I didn't warn you.
 
I've never heard of 3M 996 having sticky-shed. Are you sure that is what you have? Is it labeled on each pancake and were they sealed in plastic?
 
Beck,

The pancakes were in plastic, and in very good condition. The leaders on this batch of 996 were different from the last box: On the outside they had the 3M tartan/plaid thing, and only the slitting sequence number. At first I was suspicious. But, after peeling open a pancake, I found the usual 3M data on the back of the leader, including date codes and the "996" identifier. My good box did not have the plaid thing, and all the data, including the "996" was on the outside of a plain white leader. But the date code on the good box was from very late in the production of 996, sometime in late 1995. The box with problems is from 1991. So they may have changed the way they were putting leader and data on the reels somewhere between 1991 and 1995. Oh yes, on both boxes, the batch codes on each leader matched the one printed on the blue 3M label on the box, which clearly stated "996."

I suspect that the older, problem tape was wound much tighter on the hubs. The pancakes of the newer, good, stuff I have had all shifted on the hub. Some a little, some a lot. Shifted sideways, that is, toward where the flanges would be if it was on a complete reel. In fact some were so bad that I had to try to coax the pancakes flat again to get flanges on the hubs! This says to me that they were wound less tight than the problem box, in which the pancakes were all perfectly flat and even looked and felt tighter. On some of the problem pancakes there was a bit of loose winding at the very outside of the tape pack, even with some wrinkled tape. But it was only, literally, a few turns of tape from the beginning of the tape. The squeally, problem areas seemed to be near the hub, the inner 1/4 of the reel or less. Right where excess winding pressure working for 15+ years could possibly take a toll on the condition of the tape. Maybe I ought to run a pancake through the machine only part way and see if it is shedding before it gets to the inner windings of tape.

I really hope that this is not sticky shed. I've never heard of 996 having that problem either, and I love the stuff. Now, if it is not sticky shed, just what is it? And even if not sticky shed, does it render the tape useless? Gawd, I hope not as that means a whole case, 12 pancakes, is garbage. There is so little tape out there now (until RMGI and ATR fully ramp up production and give the big Q some competition) that it seems a sin to toss out 12 reels of it!
 
N7SC said:
Beck,

The pancakes were in plastic, and in very good condition. The leaders on this batch of 996 were different from the last box: On the outside they had the 3M tartan/plaid thing, and only the slitting sequence number. At first I was suspicious. But, after peeling open a pancake, I found the usual 3M data on the back of the leader, including date codes and the "996" identifier. My good box did not have the plaid thing, and all the data, including the "996" was on the outside of a plain white leader. But the date code on the good box was from very late in the production of 996, sometime in late 1995. The box with problems is from 1991. So they may have changed the way they were putting leader and data on the reels somewhere between 1991 and 1995. Oh yes, on both boxes, the batch codes on each leader matched the one printed on the blue 3M label on the box, which clearly stated "996."

I suspect that the older, problem tape was wound much tighter on the hubs. The pancakes of the newer, good, stuff I have had all shifted on the hub. Some a little, some a lot. Shifted sideways, that is, toward where the flanges would be if it was on a complete reel. In fact some were so bad that I had to try to coax the pancakes flat again to get flanges on the hubs! This says to me that they were wound less tight than the problem box, in which the pancakes were all perfectly flat and even looked and felt tighter. On some of the problem pancakes there was a bit of loose winding at the very outside of the tape pack, even with some wrinkled tape. But it was only, literally, a few turns of tape from the beginning of the tape. The squeally, problem areas seemed to be near the hub, the inner 1/4 of the reel or less. Right where excess winding pressure working for 15+ years could possibly take a toll on the condition of the tape. Maybe I ought to run a pancake through the machine only part way and see if it is shedding before it gets to the inner windings of tape.

I really hope that this is not sticky shed. I've never heard of 996 having that problem either, and I love the stuff. Now, if it is not sticky shed, just what is it? And even if not sticky shed, does it render the tape useless? Gawd, I hope not as that means a whole case, 12 pancakes, is garbage. There is so little tape out there now (until RMGI and ATR fully ramp up production and give the big Q some competition) that it seems a sin to toss out 12 reels of it!
Click to expand...

There is sticky shed, and shitty tape. Both would be tossed if I saw this happen on any of my machines. I never heard of alot of things that can hurt me or my machines, but ignoring it may be an ugly thing. Try a new reel of tape of the same variety just to see if the machine is causing this. Then you will know for sure. There is plenty of tape out there if you look.

Good Luck.
 
Whether it is or isn't sticky shed syndrome, SSS is not a fatal disease for the tape or the machine.

Baking tapes is a highly effective method of re-drying the binder so that the oxide stops falling off the base layer of the tape!

Baking really and truly works! I know this because I have baked old SSS tapes and they played and recorded VERY normally after the treatment AND for quite some length of time too...I'm talking months and years, I shit you not.

Not too many years ago, when you had any kind of cancer, they chopped your arms and legs off to get rid of it. Medical science has evolved and many cancer patients now live without 18th century thinking.

Baking is our modern medical SSS breakthrough.

Buy a dehydrator and step into the present day. Fix your afflicted tapes and go on to make some music with all these bones and bearskins.

Cheers! :)
 
I agree with Ghost... even though I’ve never thought of 996 as a sticky-shed tape, it won’t hurt it to bake it. And it could be sticky-shed; I’ve just never seen it with 996. Any other backcoated 3M or Ampex tape made in 1991 is susceptible to stick-shed, so I’m wondering now what was different about 996 that made me think it was immune.

The long white threads you mentioned don’t ring a bell except with really old unsealed tape that has been stored in a basement will get moldy. I wouldn’t think that’s the case with the sealed tape you have.

Sticky-shed will leave a pale glue-like substance.

3M labels and seals changed a lot over the years, as have Ampex/Quantegy, so it’s hard to tell. Some of the older 226 just had a black and white striped piece of hold-down tape.

I remember when I bought my first new reel of Quantegy 456 that didn’t have the label with the date code holding down the tape. It was just a piece of blue hold-down tape (they also used green). I thought I got ripped off, so I called Quantegy. I was relieved to find out there was nothing amiss. They had just stopped using the labels that Ampex always had. BASF/EMTEC had the most official looking seals… like you were opening some top secret “government thang.”

It may be that your tape was in the tightly wrapped state so long that it just needs to be run through a few times… or worse case – a bad batch of tape, which every manufacturer has managed at one time or another.

996 is not shed-free. Quantegy 499 is the worst for normal shedding, in my experience (not to be confused with sticky-shed).

One benefit of baking a tape is that the heat loosens the winding. After baking the pancake will flop back and forth between the flanges. It needs to be rewound and respooled at playback speed for an even pack.

:)
 
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