One way would be to use luan plywood over a form made from plywood, then all you would need to do would be us 3/4 foam cut into stone size pieces to dress it up with a little great stuff in between.

great stuff work alot like foam if allowed to fully expand, but if it is pushed down during expansion 9as for grout line) it is harder more like a plastic.

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Home is where my Haunt is!

Here is a how to on molding skulls from great stuff:

Skull Molds

However, Great stuff is pretty expensive. I thought you were going for cheap?

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- Brad

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Haunt at Red Clover
Parker, Colorado

Lowes has a case of them (about 15 or so) that are 50% off. To be totally honest, I have no idea what I'm doing. I keep going back and forth. I'm going to a meeting tonight for the folks that want it and I'm going to square out a budget with them. So, tomorrow I'm going to make my executive decision on how to make it.

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