a vulcanizer is a machine like a vice with heating plates on the top and bottom. Just google it
there is too kinds one that is for gold and silver and another for pot metal; zinc and pewter (maybe some aluminum but I don't do that).
I want to do the second kind, even though i own both machines. I'm using 9inch rubber disks for spin casting.
instead of 3d printing an object (and maybe electroplating it) it would be easier to mold it from polyclay. I know this stuffs harder than pottery clay.
what I will try is pressing out some letters with the playdow child's toy set in polyclay put it on a 9/16 piece of ploy clay make it look like a Texas belt buckle then kiln it; maybe glaze it for extra strength.
because of the simple shape I think it's worth a go. I wouldn't try anything to small with tiny protruding parts although the hook that goes into the hole in belt is exactly that.
Whether it works or not I will try to answer my own question in the form so that some other people will know if it can be done.
making stuff in autocad and then 3d printing it (in wax and cast in investment or print solid form) is much better than doing it with cnc but if this method works it will be the easyist way ever.