Material Alternative for Air Bumper

[drax]

We use a air bumper( about 4" OD) that slides in a brass tube. The material that we have used for years is Micarta, which is basically wood. We had a problem with water absorbation and the part swelling and jamming in the tube. Could anyone recommend a material that would not swell when wet and have good thermal characteristics. The environment can see about 80 C. Teflon, I believe is too expensive and we tried a moly imprenated Nylon that deformed under heat. Someone suggested puting varnish over the Micarta. Could anyone suggest a material alternative to try.

thanks

 

[etch]

hmm why dont you varnish the wood with yatchmans varnish?

just a thought.