Some time ago, I attended a very interesting course in mouldmaking and casting which took place in London. There is a surprising variety of how one can „duplicate“ (small art-)objects. This is the first post of a mini-series documenting some of my „output“.
Today´s post is about making 1-piece-moulds in silicone. Prototypes: a chameleon and an eagle´s head.
My little chameleon from airdrying modelling clay was taped on a piece of wood, surrounded by a mould wall of cardboard which was glued to the bottom. A bit of vaseline was brushed around the chameleon´s bottom line where it was uneven – and silicone was carefully poured onto it. The silicone had been prepared before by adding a catalyst to silicone rubber and very thorougly and slowly stirring it to mix the components smoothly.
Within a day, the silicone had cured and the original piece could be removed. Tadaahh- the mould was ready to use. For my „new“ chameleon I used a polyurethane resin – which as well is a material mixed of different components that would first be liquid and then turn solid – to which I added green pigments. This mixture was poured into the mould. After a few hours, the material had hardened and could be removed from the mould – out came a cute new and very green chameleon, solid and smooth. The mould still is perfectly well in shape and I reused it twice…and then decided that for now I do have enough chameleons in my life ;-).
The second prototype, my soapstone eagle´s head, was taped to a flat surface just like the first piece. A cardboardring was placed around it and glued to the bottom, the prepared silicone was poured very slowly and carefully over the eagle´s head. The beak would be a tricky part, one can never be sure where unwanted air bubbles gather that can ruin your mould. So – with a bit of luck, after the silicone had cured, the eagle´s head could be carefully sliced out of the mould – phew, no bubble-trouble! Again, the resin was mixed and poured into the mould.
I made two casts which both turned out well. One cast with tea-crumbs as a „colour“-addition giving the head a cool granite-stone-look (even though the material is very light) And the other cast with a bit of brownish colour almost implying chocolate ;-).
I sanded both a bit – and especially the „tea-head“ I find quite nice with the grainy structure. The mould can be used again as the silicone smoothly bobbs back to its form even though it has been cut to remove the prototype.
The next post in this mini-series will be real cool: how to make a green monster hand! So stay tuned…