by Mike - Alumilite » Mon Jan 23, 2012 9:57 am
I think you are close ... lets assume a qty of 5, 5" creature baits. The individual baits measure 5" long by .75 wide by .5" tall. You lay them all out and add a 1/2" around all sides to make the your mold base/box. This will be approximately your 6" long (5 + .5 + .5 = 6) and 7.5" wide (laying them all next to each other ... using your measurement) however your last dimension should only be maybe an 1" thick because you only need to cover the top of them up by 1/4" to a 1/2". So lets say your actual box would be 6"x7.5"x1". Now the material needed would be 45 cubic inches which is just over 2 lbs. BUT you also get to subtract the volume of your creature baits themselves. So I would assume 2 lbs would be plenty to make this 5 cavity mold.
You only need approximately 1/4" to a 1/2" around the outside of your pieces for your mold box. Space inbetween the actual lures themselves does not need to be more than 1/4". Pack them in there and save on the silicone.
When you start dealing with bigger muskie or saltwater baits, you will need to start increasing the size of your perimeters slightly or make sure they fit back into the mold boxes to act as a support so the molds don't flex when being poured.
Mike
Alumilite