Originally Posted by moparx
what about putting a small o-ring [that just fits] inside the cap ?
or use a leather punch to make a gasket out of an old inner tube [using the "hole" piece created by the punch] ?
that may seal the cap to the fitting somewhat.
just tossing something out there.
beer

Most of the caps do have a Silicone/Viton/rubber type seal but the caps being plastic and exposed to heat were a poor choice IMO.
I've found some slip over covers but I was curious if anyone knew of a source for metal caps beer

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