Any tips on how to repair cracked rubber CRT masks like the green ones that surround the CRT in Zenith porthole TVs?

Carl

I would try rubber cement like the kind you would use on tire repair. And then paint it to the color you need it to be.

The green mask around Zenith tubes is plastic. Not rubber.
Bill Cahill

Yea, I know it plastic. My porthole has a plastic one. Iv'e got a seeburg trashcan jukebox and the dome was cracked real bad on it. And the rubber cement worked great on it.

I wonder if using a fiberglass cloth repair like used on auto bodies would fix the mask?
I would think it would strengthen the mask. Certainly would require some sanding and painting.

Carl

That could work too.

I had a cracked mask on my DuMont. After gluing it back together I reinforced it on the back with some epoxy putty. But in my case the back of the mask did not sit against anything, so there was room for the blob of epoxy putty.