"Christopher Tidy" wrote in message
...
Gunner Asch wrote:

If its not dynamically loaded..should work fine. If its loaded...it wont
last as long as other better Stuff will.

Thanks for the thoughts. It's a piston in a miniature air pump. Here's a
picture. The plastic layer is over the knurling you can see:
http://www.mythic-beasts.com/~cdt22/pump_piston.jpg

I had wondered about oil-filled nylon. It's definitely not epoxy as I've
been told it was thermally moulded.

Chris


It is too clear to be filled with anything. It could be nylon, polycarbonate
or even low density polyethylene. If you can do destructive testing,
strong acids will eat nylon, and ketones (lacquer thinner) will eat
polycarbonate. Polyethylene will be more resistant to both, but it is not
compatible with mineral oil.