How to calculate volume for a pourable mold

Calculate using the standard formula for volume (Length x Width x Height) for both the original item & the mold box (subtracting the volume of the item from the volume of the box to determine how much mold rubber you will need)

OR

After you have secured your original in a mold box, fill the mold box to your fill line with either dry rice or clean, dry play sand. Then, pour off the rice (or sand) into measuring cups to determine the volume you will need.

*Caution: We don't recommend using water or other liquids to determine volume because when urethane comes in contact with water, it foams like a volcano!

Different types of sealers

The type of material you original item is made of as well as the type of mold material you want to use will help determine what the best type of sealant would be for your project. We have a product called Super Seal which works really well for virtually everything you will need to seal (clay, wood, plaster, porous metals, etc.) and you can even clean it off the original with soap and water when you are done if you like. But, if you would like another option for, say, silicone mold rubber - spray acrylic works great (Krylon Crystal Clear). There aren't very many things that silicone will acutally "stick" to (silicones, glass, glaze on ceramics), but silicone can achieve what is referred to as a "mechanical lock". Picture putting a skeleton key into a lock and turning it a quarter turn...its not "stuck", but, you aren't going to be able to pull that key straight out.. it has a "mechanical lock". Silcone will go in as a liquid & firm up to a solid to form a "mechanical lock" if you put it against an unsealed porous surface.