I think several months ago I had finished the demo of making the molds for the Angry Clobber Monkey. Go back to Monday, March 10, 2008 that was the last entry on mold making. Now the silicone has been poured, most of the time it takes 12 hours or so to set up depending on how much catalyzer you mix in. When it’s good and solid tear away the foam core and gently pull apart the mold halves. Pop out the clay sculpt and powder the mold. Now it’s ready for resin.
Resin is a pricey material, and on small budget projects we want to waste as little as possible. Here’s a technique for getting a good estimate of how much resin will fill the mold. Some people like digital scales, I’m a fan of the old school 3 Beam scale. Easy to use, I’ve had this one since 1995 it was around $200 then, and that was a big investment! It’s paid for it self many times over
Rice is a good filler for guessing weight. Fill the mold with rice, weigh the rice. I am casting the masters so I want the pieces to be solid.
When I make the prototype it will be hollow. Whatever the solid weight was go with 50% for the hollow weight.