making a mold

[lakefront6]

how much siklicone should I need to buy to make a mold 6"x12"x3"thick.

[dahlberg]

I would suggest going to the Alumilite site and look at the volume calculator. My guess is around three lbs, but the calculator will dial you right in
good luck,
L

[Mike - Alumilite]

The basic process the calculator will walk you through is taking the volume of the piece and subtracting it from the volume of your box. This gives you the volume of where your silicone will fill. There are approximately 21 cubic inches per lb of silicone rubber. The volume calculator does this for you if your mold box and part are either round or rectangular. http://www.alumilite.com/CalcVolume.cfm