The previous sculpture can be found here and the fibreglass mould making can be found here. This was an experiment with intrinsic painting and silicone pigments and although I think a number of things could be better about the finished effect there are a number of things I also quite like about it.
After finishing the sculpture and making a two part fibreglass mould I then spent some time cleaning the clay out of it. I'd advise spending some time doing this else the clay will end up on the finished product and obscure the detail that you spent time sculpting. Once this was all clean I then painted silicone, layer after layer into both halves of the mould:
I then bolted the mould back together and ran silicone through the mould to seal the silicone skin.
After doing this I created a mechanical bond so that the silicone skin would be attached to the urethane. I then set about mixing expanding urethane foam and pouring it into the mould.
WARNING: expanding urethane foams are toxic. Do not attempt this without proper masks. Make sure you are gloved, wear long sleeved clothes, sealed shoes and some kind of eye protection. Read the MDS and TDS and seek instruction.
First I poured the foam components into two separate containers, as rigid foams are not a 1:1 ratio mixture. Then I quickly mixed the foam together. I did this by hand and poured in two batches.
The foam rapidly expands and would have busted apart a mould that was not bolted together. This is also a good thing as every bit of the cavity in the head was filled up with foam. Alana took some pictures and made a short 'arty' video of the expanding foam doing its thing:
After the foam had expanded we noticed that insects were attracted to it for some reason:
The bottom bit that 'bubbled' out of the top of the mould was then hacksawed off. After doing this it is not a bad idea to seal the bottom of the foam that will face downward as bits of foam debris break off everywhere. The finished silicone bust was then pulled out of the mould. I think I could have created a mechanical bond all around the edge at the bottom of the silicone positive as it has a bit of a 'skirt' thing going on. After pulling it out I had to go buy scissors to trim the mould seam You can see the mould seam here, much better than I thought I'd get but still a mould line:
This trimming work took me some time:
After doing this I then mixed up a small batch of silicone and brushed it along the mould seam on the silicone corpse bust. Then I brushed the silicone with a couple of smoothing and dulling agents to blend it in with the existing silicone. Then finally viola!
Actually all up it took me a fair bit of time to do this, as well as a lot of learning, practice and research. Counting sculpting, mould making, cleanup, painting in silicone, pouring foam then seaming it took me ten days to get this done, but worth it because of what I learned along the way!
Hope you like it!
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