Does anyone have experience milling 2 part molds from POM?
I’m interested in the quality of perfect 90° angles, that can be achieved.
On the parting line any inperfection causes flashing (material creeps in-between both mold parts.)
Did anyone do this and has photos of what I can expect?
I have not done parts for molding myself but I did cut POM material. It cuts relatively easy and has mirror-like finish. My partners who work with plastics say that POM is used in medicine and you can get up to 0.01mm accuracy.
So I guess you may expect some pretty good results.
I’ve done it, what are you casting in it? I had a bit of trouble getting wax to release.(wax and plastic are cousins I guess) And the mold not holding perfectly flat, I solved these issues but Aluminium was easier to use, even with 0.6mm end mills.
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@Paul_Shaw
I’m fasting soft parts in silicone.
(non-soft materials I can sand and postprocess to get rid of flashing)
Thanks for the photo.
I see a tiny bit of flashing at the seam but then again, the surface wasn’t machined to a polish.
With enough, evenly distributed clamping force this may work out and is definately worth the effort to try it.
Thanks!
@Paul_Shaw Have you tried spraying the mold with dry PTFE? I think if you spay the mold with PTFE the parts will be removed without any force.
Yeah I used very diluted dish soap, dried in the 40 deg sun then place in the freezer post casting. The other thing with pom vs aluminium is it takes a lot longer for the wax to cool. Yeah I clamped the mould between 2 plates with bolts through them to help. I had a mistake in the cam with that one I think I had to sand the alignment pegs down to fit so it wasn’t as perfect as it could be. Also I cast the silver way to hot. It was my first attempt so I had no idea what I was doing.