past nastification the casting process we use is" lost wax". first step is to make a rubber mold either with a vulcanizer which uses pressure and heat, or a two part rubber mix for items that can't take heat. cutting the mold in two to release the item is challenging and an art of it's own. I have only cut 2 and it was a little scary with the exacto and the nature of the slippery rubber mold.
once we have a mold then we shoot waxes. basically a pressurized hot pot of wax. I think it is exactly the same set up as the plastic castors.
after shooting waxes of the desired amount, we build a tree. a central sprue with the waxes attached (with a hot pen and sticky wax). then we put the tree in another mould and cover with investment (very similar to plaster). after drying for 24hrs we put that into a computer operated oven to burn out the wax. 5-24 hrs after that we pull it out, heat molten metal, put the mold on a casting table that pulls a vacuum, and pour the metal in while still heating with a torch.
then we let it cool(some) and dip it into water to cool it off and release the investment. if everything worked we have a metal tree of whatever. then cut, trim, smooth, buff, bam finished piece
blue plastic original,purple wax, finished brass pieces
wax tree
silver destroy tree
my friend who helps me with casts blog-warning foodie,knife porn, and jewelery
http://paulvern.tumblr.com/
