How to Calculate Material Volumes
Many of us just guess the amounts of mold making and casting materials needed for a project. But in guessing we are very seldom right. We either under mix or over mix our materials. Over mixing means waste. Under mixing means more work or worse we don’t have enough stock and we are caught short. Yet a mold maker can easily calculate the amount of silicone, resin or gypsum plaster materials needed down to a fraction of a gram. Here’s how:
Please view the video to the video on the left for an explanation of tip and tricks in how to make more exacting material requirements.
You can use the calculator section of this page on the left side of the page to determine the exact quantities of mold making or casting materials needed. Just make the measurements and then plug in the sizes of your mold container and model into the appropriate box on this page. Then click calculate. It will do all the work for you.
For those who prefer the written word, here is a short explanation of the procedures.
Make a note of the volume constants:
Silicone Rubber: 0.740 ounces per cubic inch.21 grams (453 grams per pound).
Polyurethane Resin:0.544 ounces per cubic inch
Gypsum Plaster: 0.490 ounces per cubic inch