by Mike - Alumilite » Wed Jul 09, 2014 8:58 pm
The four piece mold was an SLA (3D printed) original off of some Solid Works drawings that we did at Alumilite. Not realistic option for most unless you are ready to go into production and want perfectly symmetrical designs.
You can do this same thing manually by simply claying each section up individually. So basically, you would have your left half side of the tail section showing and everything else would be in clay or mold box. Then pour it with rubber. Then flip it, cut locators and pour the right side (same way you'd make a two piece mold). Make sure to mold release inbetween pours. Now you have your tail mold halves. Then cut locators on the vertical side (facing the body), then repeat the process for each half of the body. Where the body halves meet the tail halves, they will locate.
Once you have all four pieces of your mold, remove your original, put the tail sections together, stand it up so the hole and locators are facing the ceiling, pack some clay in the tail and sculpt a little tongue that hangs out of the tail portion of the body, then construct a mold box around the two halves of the tail section, mold release it, and pour a 5th mold of the tongue section coming out of the tail. Then cut to the tongue or simply don't pour the rubber over the tip of the tongue. This will locate in the two halves of the tail mold and give you a place to pour the tongue which will create a stem for the body pour of Alumisol to wrap around and better adhere to the tail rather than only having the tiny flat seam to adhere (which it wouldn't do very well). That's why we make the tail first with a tongue/stem that will dangle inside the body mold and be encapsulated and bonded to the body pour of Alumisol much better.
Hope that makes sense.
Now for an even easier way of doing it ... make a mold of the tail section separate, pour it separate and then simply insert in into the mold before pouring the body similar to the way I made the Bull Dawg style bait.
The first way is more professional and looks better but the second way allows you to much more easily create multiple tails with much less work and requires much less time to mold.
Mike