Quote:
Originally Posted by Sickie Ickie
How did you make the molds for the skulls?
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I used 1 part clear silicone in a tube (ala home depot) with some glycerine and acrylic paint to help it cure. (5 drops of glycerine per ounce, 1 drop paint per ounce) the paint does double duty, it helps the silicone to cure and also helps you know when everything is mixed together.
the skull I used for this mold was foam, it was horrible to work with, the silicone would not release from the skull after it cured, I ended up applying several coats of latex paint to the foam skull and then a very light coating of vaseline to help the demold process. (if you use too much vaseline, you wont be able to get the silicone on to the skull)
If you use a plastic or resin skull, you will not have any trouble with the silicone sticking.
I applied a thin first coat with the silicone using my fingers so that I could work it into all the small cracks and grooves, once that cured, I plastered on a second thick coat.
once the mold was complete, I made a shell out of 4 layers of cheese cloth and plaster of paris it will help hold the shape of the mold while the foam is curing.
If anyone is going to attempt using great stuff to make foam skulls, a couple words of caution, first, spray the the mold with water before filling the mold with greatstuff and then once the mold is filled, spray the greatstuff with some more water, this is the only way I have got greatstuff to work, otherwise it doesnt cure for me.. also, if you decide to go the greatstuff route, there is a 98% chance your skulls will not hold thier shape, the only way I can explain it is that they shrink, causing wierd deformaties, for my project, a perfect skull was not needed, but if I wanted a perfect skull, I would skip greatstuff and use 2 part marine pourable foam
Here is a link for more information on making molds with silicone caulk.
http://forums2.gardenweb.com/forums/...385422593.html
Hope that helps.