Mold material for lost-wax casting?

August 8, 2005 7:41 PM

How do you make a mold for lost-wax casting?

My dad wants to cast the pawn from the Lewis Chessmen set in bronze. I picked up a reproduction pawn made out of marble dust and resin. He's intending to do this using the "lost wax" method of casting...but he's wondering what material he should use to make the initial mold of the pawn.

Anything else he should know about this process, or other insights?

posted by Vidiot to sports, hobbies, & recreation (3 comments total)

first, make a mold of the pawn with silicone rubber. second, make a wax" pattern" (copy)using the silicone mold.third,
invest the wax pattern with refractory plaster. fourth, melt/burnout the wax(it is lost) and fill the (hot) plaster mold with molten bronze. The fine folks at R.G. have much more in the way of advice and materials.
posted by hortense at 8:51 PM on August 8, 2005

Dude, the wiki on it is quite good, too.
posted by dreamsign at 10:44 PM on August 8, 2005

This is Dad. I've cast all the pieces except for the pawns; used a kit intended for casting in plaster.

The molds barely held up with the hot wax for the 4 pieces of the rest of the set; will definitely not hold up for all the pawns.

So, as Vidiot said, I now have a pawn to use.

RG: have you dealt with them? With silicon rubber (aren't those two materials completely different (I'm an engineer at a plant that makes organo-silicones))?

Thanks, steve45750
posted by steve45750 at 9:16 PM on August 12, 2005