I'm trying to cast small pewter medallians with detail similar to a state seal; an image with lettering around. I've tried rtv molds but they provide no detail, maybe a gas venting problem? Also tried sand mold which was a bit more successful but left a grainey texture and some detail loss.
I have no high temp facilities at this time so I'm limited to low temp alloys.
Any suggestions or comments on how to accomplish this project?
Thanks,

These low temp melters are cast commercialy in Silicon rubber molds using a centrifugal method. See Cast Tin for some of the supplies and equipment for this