Melting Clock prop - silicone or urethane?

[cbach]

I’m making a Salvador Dali Clock prop that will slowly melt over about 15 seconds. It will actually just bend in half since the top and bottom halves will be supported by a solid half moon to keep them from flexing. A pivoting flat bar will keep it solid looking till the effect happens.

My 1st question is what Shore A harness of material would be best to make it in to "melt" properly? Is silicone the best material as well? Or urethane rubber?
2nd question is can I cast in a white material and brush in the gold to get the metallic look for border?

I would appreciate it very much if anyone knew what might work best for this effect. I have the mold worked out, but since materials are so expensive…I don’t want to get the wrong flex multiple times.View attachment 1375487

 

[robstyle]

This may or may not be what your after, but, Crayola Crayons. Melt some in an old clean soup can on the stove, and thats your casting material, dump it in your mould, let it cure to room temp. I had to do an effect where a bullet was made out of a coin, smelted over an open fire, then poured into the bullet mould, demoulded and loaded into a gun all in one take. Crayola brand crayons have a higher wax content and they are already colored.

For a metlign effect if you place the clock on table surface, and heat the edge, the crayons will melt where the heat is... Same for the overhang and drip side. Blast it with heat and it wiull melt practically. Collect the melted crayons and reheat it, make a new casting... try again.