Abomination: molding and casting

Finally I have completed the next step in my project. It is probably the hardest one of all in this process of making the clay Abomination sculpt into a usable, flexible action figure. I encountered several problems along the way and at one point I was afraid my great sculpt may have been wasted. But I have prevailed and now have a successful casting of Abomination. Final pictures are at the bottom but I have also documented the making process step by step, so take a look!




First I began by making the form for the plaster mold using a piece of sturdy foam board with clay walls bordering it. Then I mixed up some plaster and poured it in. While it was still wet I placed the clay sculpt in, frontside up. After trying to even it out and make it cover all the back areas (under the hands was difficult) I ended up with this...

His feet must be aligned with the bottom in order to make an opening to the mold. Unfortunately this first mold was a failure (you'll see why)

Next I mixed up some more plaster and created a front half of the mold. I did not yet realize the mistake I had made however. The problem was revealed after opening up the mold

Those are the soles of his feet there.

The problem was revealed when I tried to pry open the two plaster halves. I had not realized that they would be too thin and weak to stay intact, so the top half cracked into 3 pieces when I tried to force it apart.

Amazingly the sculpt was still intact aside from some minor fixes (like his head being ripped off). With just a few touch ups I restored it well enough and then was able to redo the top plaster half.

The first time I actually forgot to put clay pieces around the edges in order to make wedge spaces to make prying the mold apart easier. (in the 4 corners)

The way I ensured the strength of the plaster was by putting some of this netting cloth in the plaster layers while it was wet. This time I ended with a stronger and thicker front half.

Of course, there was another problem, the back half was too weak. So when I pried it apart this time that half cracked!

Once again the sculpt had survived so I redid it the stronger way and finally opened it up and was able to remove the sculpt, leaving two decent halves!

Now I could begin the casting process. I wanted to use silicone rubber, which would have made it easier, but I wanted to conserve that for my next project (spoiler!). So instead I coated the mold with latex that I would then fill with expanding foam.
                         That's the latex coat below.

Then I put the two halves together, mixed up some 2-part expanding Poly-foam. I was unsure whether this would work since it The stuff is a bit unpredictable and I didn't know if it would fill the whole mold, but man that stuff expanded. After pouring it in through the feet it unexpectedly started shooting out and overflowing. It has a very quick work time (less than a minute) before it starts expanding like crazy! Then all I had to do was wait a couple of hours for it to cure.

I was quite surprised by the result, he turned out a lot better than I thought and the latex looked great and worked well as a skin. The foam had expanded all the way too his hands, minus the small fingers, but that was ok for now.

I was quite amazed with the result once I freed him from the plaster. After trimming off the extra latex on the seam he looked great

The latex picked up the detail quite nicely

Here he is compared to the original clay sculpt (left), minus it's head.

I sort of forgot to put a wire armature in him so right now he is not posable. This is only a test version really so I will eventually get around to doing a recast using silicone rubber.

All in all it was a much better success than I expected! the only thing left is to paint him. That may have to wait though because I need to start my halloween project (post soon to come)

here is a video to see him in action!