Is plaster heat resistant?

Question

I want to make a mold, Somthing without the need to machines, nothing big just a simple mold of anything I want. I figured I can use metal to make the product, but I was wondering if plaster can resistant heat at all to be able to make a metal product from a Plaster Mold.

Anyone know?

Answer 1

If what you are melting is lead, zinc, or tin, then plaster can be used to mold it as they all melt below about 600F. Plaster of Paris starts to disintigrate at about 900F when the water of chemical composition is driven off. Molds can be made using investment (KerrLab http://www.kerrlab.com/index/kerrlab-jewelry-home/index.cfm ) which is designed for high heat and will cast brass, bronze, aluminum, gold, silver and platinum.
A similar product can be made with 50% plaster and 50% silica flour available from pottery supply companies. It is, I am told, more fragile than investment.
Investment must be encased, usually in a metal sleave because it will crack and leak if not.

Answer 2

Yes.. plaster can hold metal... i used bronze as my final project in my hot fabrications class... i made a wax structure resembling a human heart and then made a cast of plaster in a square cut in half with vaseline with a hold at the top to (get rid of the wax and pour the bronze into) then i heated up the wax inside the plaster and drained it so it was a hollow plaster mold then i wired the 2 part plaster together and poured bronze in it and let it sit in a sand box.. so Yes you can use for bronze.... double check for other types of metals and the thickness of the plaster ... but be safe as always!

Answer 3

plaster is used in bronze molds, but it is heated up to temperature before the molten bronze is poured (a ruptured mold will really spoil your day there)
i'd take a class or two on the subject of metal casting and sculpture before attempting anything though...you will need a system not readily available at home.