At 10:34 AM 3/12/2005, Stefan Trethan wrote:
>On Sat, 12 Mar 2005 10:24:58 -0500, Dave VanHorn <dvanhorn@...>
>wrote:
>
> >
> > You may be aware of this, but some plastics, like nylon, absorb water
> > nicely, and swell.
>
>
>Yes, i was aware of nylon, i know PE ans PP and PVC are ok with water, and
>i expect PTFE to be ok.
>
>Do you know about delrin (isn't it similar to nylon??)
AFAIK, delrin is ok.. We had an embarrassing incident with a bearing that
was nylon vs delrin, because the engineer in charge insisted on using the
materials with the lowest possible coefficient of friction. The prototype
worked fine in wisconsin in the winter, but failed miserably at a demo. The
bearing locked up so tight you couldn't turn it with pliers.
Did I mention that the demo was in Cancun?