Yes! that is the word I was looking for.:thmbsp:

"Phenolic sheet is a hard, dense material made by applying heat and pressure to layers of paper or glass cloth impregnated with synthetic resin."

jr

Jr and Charles' discription of the scuff pads is right on. I couldn't think of the word phenolic either in my post. In better light the discs are not maroon as I stated but a dark mahogany brown with a shiney coating on the front and flat black on the back.

-Steve D.

On this Vacseal stuff, does it dry hard? I can imagine if it does not remain soft and squishey on a surface that does not now have a leak, then if one develops it will not be "sucked" into the leak and seal it. Kinda like the self sealing tires, the stuff inside is always sticky. I wonder is a good chemical clean of the area, and application of a silicone glue or something that remains rubbery is not the best to apply to a surface that may or may not leak at a known spot......

I felt the Vacseal on one of my tubes about a month after sealing. It had cured beyond the "almost tacky" stage, but it didn't feel as hard as, say, cured varnish. This was casual feeling with a fingertip, not scientific inspection, and there's no way to know what's going on under the surface, of course.

I've been told that these leaks, when they happen, are at the microscopic level. If you apply something like glue, my question would be whether it's truly impermeable in the first place. A rubber balloon seems impermeable when you blow it up, but it eventually deflates because gas passes through the material.

We're all just guessing until John & Bob can apply some science to the question. I put Vacseal on my tubes on the theory that it probably won't hurt and it just might help. They don't leak now, but they had gotten through the previous 50+ years without leaking, so the fact that they haven't leaked yet tells us nothing. Vacseal is expensive stuff, but cheap compared to the cost of a good 15GP22.

Phil Nelson

I may be off base here, but I believe that the very tiny leaks that we are trying to stop on CRTs are much too small for a liquid like vacseal to be "sucked into". I look at it as a dense low-vapor pressure coating that essentially provides a second containment wall, in case the first fails. I have painted it around CRT neck pins, base pins and tip seals as a preventive measure. I have no statistically significant proof that it did any good, but in those small quantities, it is pretty cheap per application.
jr

You're not off base. But, Vacseal is intended for small leaks. If the leak is too large it gets sucked in too much and doesn't plug the hole. In smaller leaks it thickens as the solvent evaporates and gets too thick to pass further.

Vacseal is intended to be cured at temperatures above 200C. It cures below that temperature, but not as well. The very property that makes it a good sealant prevents the solvent from evaporating rapidly once a skin has formed. Heat helps.

Unopened bottles have a shelf life of 3yrs. Cans, 3 months. I've had opened bottles that refused to cure even with heat. I suspect it cures much the way shellac does, and doesn't.

The datasheet says that the surface will always seem a little sticky so don't worry about that.

John

OK So who was the winner? Only one bidder took it for 5K.

Yep, first bid at 45 seconds left then he hit it with another bid in the last 5 seconds to block any other potential last minute bids.

Hes fairly local so thats nice.

Not me...

Charles

Not me either. I was tempted, but didn't feel right dragging it across country.

John

Well, I wish I could say that it was me. I was tempted as well but don't have that kind of money and as mentioned above, don't have the means to cart it for all of those miles. It sure is a piece of history. And I would guess considering what it is, it was worth that money.

Let's hope the new owner surfaces and that we find out the status of the CRT. Sure would be nice if it works! That chassis would be a candidate for a very slow restoration with the stuffing of original capacitors. Wadda ya think?