On Tuesday, November 3, 2015 at 11:30:55 PM UTC-5, A2 wrote:




I'm starting to think aluminium might be the best as we know we can get
a polished finish. Not so sure we can get this with UHMWPE.

I was wondering if aluminium molds are routinely coated with something
like that used on non stick fry pans.


You might try UHMWPE anyway. You have to have very sharp cutters and take off about .1 mm on the final pass. And you may be able to flame polish the UHMWPE.
Unfortunately flame polishing oxidises the surface and that is not good for releasing the part from the mold.


UHMWPE is a lot cheaper than aluminume, so it might work out. You can find heaps of posts about using PE for molds on the internet all posted by people with more experience that I have.

Dan