I got my vacuform machine two weeks ago and I’ve played a bit with it, but mostly I’ve been getting my plaster molds ready. That is, until yesterday when I set the machine up to vacuform both halves of the flea and some low-relief louse legs. I used a thicker Vivak (.040) because the draw was a deep 5″. Our operations manager, Rich Boardman came in and helped me with the first pull.
We got the Vivak nice and hot until it sagged, turned on the vacuum, and slammed it down over the molds. It went down only about 3″ and there wasn’t any detail to speak of. I had a heat gun going to heat the molds and used it to re-melt the plastic all the way around and bring it down over the molds. The detail was less than impressive and I felt the casts were not usable.
I get grumpy when things aren’t going so well, but I know it is also a necessary time when creative problem-solving has to kick in. I had already tried to cast in epoxy, but being unable to control the thickness of the cast, I gave up on that idea. Now, I took the reject vacuform casts and tried to fit them into my silicone molds. They were nice and tight and were close enough so that the molds didn’t distort, so I took them out of the molds and mixed up a large batch of epoxy with oil paint. I poured the epoxy into the mold and quickly pushed the vacuform cast into it. The epoxy squeezed out the sides, filling the mold with a thin layer of epoxy backed by the Vivak cast.
I’m still working out this idea, but I’m encouraged by the initial results. Today, I will color the inside with colored silicone caulk and tomorrow, I will epoxy the two halves together.