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Improving the surface finish of PTFE plate

Hi,

I am trying to improve the surface finish of as-received 1/2" molded PTFE sheet/plate used as a casting surface for a polymer casting operation. The surface is pretty smooth as is, but because the plate is being used to ease release of a cast polymer and not as a bearing surface, honing the plate with a mating part is not an option.

Is it a good idea to use standard aluminum oxide or silicon carbide abrasives? Or will abrasive particles embed themselves in the plate?

Best Regards,

- Sevan

P.S. Finishing.com is a great resource. Thanks guys!

Sevan Oungoulian
Research assistant - New York, NY, USA
April 6, 2009

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PTFE is an excellent low friction surface (if not the best available!), but it is very softy and can be difficult to get a good machined surface. Any process you use will have limitations, but if you use micron sized diamond paste (as used in metallography) and be very gentle, you may get away with a good enough surface. have you considered using a different polymer, such as PVdF - this is much more an engineering polymer than PTFE and you should be able to machine the surface to a better roughness

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
April 9, 2009