What's the best way to make a custom mold shape?

Question

I want to make a mold of my own design, the problem is how do I do it? I have tried using modeling clay to make the shape of the item so I could make a mold from the clay after I bake it. The problem is the clays form is only as good as I can make it, so it looks rather sloppy. What should I use and/or how should I be doing it to make something I can use to make a custom mold from?

Answer 1

The question is what are you trying to cast it in and what exactly are you trying to do? You use different kinds of molds for different kinds of castings.

If youre casting latex you can use a plaster mold if you're castingcertain plastics or foams you can use a urethane based mold but you still have to back it with something hard so you still may want to bust out the plaster.

The monster makers has some molding info as well as the monster list of halloween projects. Also do a web search for mold making and see what comes up.

Good luck

Answer 2

What do you want to mold?

What material do you want to mold?

If you are just starting out, I suggest starting with a simple press mold of a real object or one you've sculpted in clay. If you are successful, you can move on to two-piece molds and so on. Start with some simple plaster that takes about 20 minutes to become hard.

Answer 3

I make my models of plasticine clay, which allows constant reworking of even minor details until acceptable. If properly shaped, a sectional plaster mold can be made off of it, but I usually make a latex negative to pickup all the details, back that with plaster for strength. I cast wax positives, plaster copies and investment cores.