I tried making the negative mold for the Cronus prosthetic today and was pretty disappointed with the results. There are certain things you just have to learn on your own I guess and that's about the best thing I can take away from it.
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It took a while to demold, and at first I thought for sure it was garbage, but once I got it free I found it was actually workable with a little fixing, which went well - until I noticed 2 major imperfections that were just no way around. So because of two imperfection about a week's worth of work is trashed.
There's supposed to be a seam, where the negative mold meets the positive that's the edge of the prosthetic - in this case there was a massive air bubble and a half inch of the jawline was ruined. If I tried making a foam prosthetic of this - there'd be a massive ugly looking wart on his jawline or it just would've have torn the prosthetic when I removed it from the mold.
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Here a good inch along the side of the nose had been chipped away. I might have been able to get away with this, but again it was right along the seam and I really have no idea how bad this would have looked.
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The thing is the sculpture is destroyed in the demolding process - it actually has to be in order to preserve the positive mold. One problem was dealing with the UltraCal, it's a tricky thing to work with - it stays too thin to do much with for so long and when it begins to set, you just have a few minutes or the whole thing is wasted. Luckily you can just add more, but it can cause some unwanted lines in certain cirsumstances.
Also, I used these resin horns from a prosthetic I bought on the one I was making and a couple were also destroyed in the demold - so this is a bit of a setback and a massive dissappointed really.
Although, I did learn a lot in all the mistakes I made. Doesn't change that I lost a lot of work, but I know better for the next time around. I don't know when I'll have the time or materials to make another mold of Draper's head - I still have the original, but it has problems I was hoping wouldn't cause more problems, which it did - but I guess that'll be the next step.
I have some ideas on how to make it work better next time already and some ideas to remove some of the "one use only" aspects of the process. We'll see.