Repair or Replace Volume Control? Airline 62-181 (1931).

[Winky Dink]

This is starting to sound like a Slip Plate promo (I do not have stock in this company).

It's an industrial metal-to-metal lubricant, and it sets quite hard. I expect it to be more than adequate for my use. I originally bought it as a CRT coating (based on someone else's experience) when I couldn't find the usual materials (Aquadag etc.)

https://picasaweb.google.com/lh/phot...eat=directlink

In the short term it works well. After hooking up the rebuilt condenser block on the bench, the volume control worked properly.
-Winky

[Winky Dink]

A quick update on this. I wouldn't want someone in the future to follow the previous advice in this thread and run into the long-term failure that I had.

Over a period of months, the rheostat resistance continued to decrease. After a year it was hopeless--full volume at the lowest setting. Either the Slip-Plate continued to lose volatile components or the graphite was burnished and condensed where the sweep contacted the surface.

I decided to try plain graphite mixed with epoxy cement. I used the tiniest amount of epoxy that allow me to make a paste with graphite and applied it to a fresh piece of card stock cut in the proper shape to fit the rheostat. After many trials I found a mix that would give me a smooth increase in volume--but in only one third of the rheostat's normal rotation to reach max volume. That was good enough for me.

It's been almost two years since I did that, and it's still stable. The radio is only used about once a week, so in the very long term the rheostat could still fail. I'll let you know how it works five years from now, so stay healthy.