: Build Log
Making scale pilots and replicating them.
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Apr 22, 2011
, 02:06 PM
USA, TX, Fort Worth
Joined Sep 2004
What can you say but Wow! Beautiful work Warhead.
My mold turned out fine so I figured I would go ahead and show how I cast a figure. Its simpler than making the mold.
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I've removed the legos
and pried the mold pieces apart. The silicone really wants to stick together and this time the guy didn't want to come out either. Gradual stretching and gentle prying here and there rather than force gets it out.
I spray on a coat of auto primer. It gives a nice paintable surface to work with. Also it helps aviod the imperfections that sometimes show up on the surface of the foam.
Here's the two part foam I use from Smooth-on. Again a 25$ trial size that lasts and lasts for what I do.
I use syringes to measure out equal parts.
Stir in a cup for 45 seconds.
and pour in immediately. There's virtually no pot life to this stuff.
It starts to expand immediately. It hardens quick, but I find it is still fragile for a couple of hours.
If my patience holds out I try to wait 3-4 hours before I mess with it.
Silicone comes right out of the plaster backing, then it's easy to gradually peel the silicone off the casting.
Take the flashing off with a little file and use some lightweight spackle to fill in any imperfections and seams. At this scale, the tip of the nose usually gives me trouble.
Try try again. Here's the rogues gallery of my frankenstein experiments before I settled on a material and technique for casting.