Today I tinkered around with my carving wax casts. I made two casts yesterday. The first one was left in the mold about a minute or so before I emptied the excess wax out. The thickness of the wall in the spare looked like it was about 1/8th inch thick. That casting turned out to be about 1/16th inch thick! Wow! That means the spare is giving me inaccurate information! Maybe it has something to do with the temperature of the wax I am pouring? I poured the first mold at about 160 degrees Fahrenheit.
The second casting was left in the mold about two minutes. Also, I poured it at a lower temperature of about 150 degrees Fahrenheit. It came out about 1/8th inch thick. The thickness of the wax in the spare looked to be more than 1/4 inch thick!
From this small sampling, I think that both the temperature that the wax is poured, and the time that it is left in the mold, are more important indicators of wall thickness than how thick the wax wall looks in the spare! I'll need to keep track of this information.
What I really like about both of these castings is that when I thump them with my finger, they sound like plastic. They are hard. They can be carved with my paring knife. They can be drilled with a drill bit. They can be sanded smooth. This is why Martha Armstrong-Hand worked with carving wax!
The carving wax pattern can be used to make silicon rubber molds for resin casting, or plaster slip casting molds for porcelain. I am just now beginning to understand why professional designers use Industrial Design Carving Wax! This material is incredible.
It doesn't matter what you make the original sculpt from. If you can make a rough shell mold of plaster from that sculpt, then you can cast carving wax into that mold. Once you have the carving wax pattern, you can add/subtract to/from that pattern, and finish it as smooth as you want to finish it. Then you can make your final casting mold from that pattern. This is the secret of Martha's Method. I haven't seen it anywhere else.
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