My polymer clay jewelry masters have no compatibility issues with the silicone materials I use to make my molds. No mold release is needed, and any heat generated by the mold material curing is never a problem. This is a big advantage for mold making. Mold making, in it's self, can be a real headache. No need to worry about my precious master being ruined. In fact, with proper storage, the same master can be re-used to make countless molds.
Polymer clay sticks well to glass. I always sculpt on clear glass, so I can peek underneath and check for voids. Once "cooked", the sculpture is easily pried loose from the glass.
Polymer clay is cured by heating in a home oven or toaster oven. The clay I use, is fully cured by heating for 15 minutes at 265 degrees, for every 1/4 inch of thickness. One trick is to partially "cook" the clay for say 10 minutes, then progress to the next step and partially "Cook" again. This can be repeated over and over until the sculpture is done and ready for full curing. Did I mention that raw "uncooked" polymer clay sticks well to cured clay? That is another advantage. You can keep adding layer upon layer to your design with no adhesive required between layers.
Once cured, polymer clay becomes permanent and hard, and can be drilled, sanded, polished, sawed, glued, screwed and painted, just like a piece of PVC plumbing pipe. Because it is the same material. Polymer clay is Polyvinyl chloride (PVC) with liquid plasticizers added to make it malleable and clay-like.
I buy my polymer clay at the local Hobby Lobby, for $8.00 per 1 pound box. Last week, I bought a new box, and the price had gone up to $12.00 for the same 1 pound box. But, considering how many jewelry sculptures I can make from a pound of clay, that's still not a deterrent. I buy Super Sculpey in the green 1 pound box. I am not concerned about the flesh pink color, since my jewelry masters are not the finished product. I am happy with the consistency, straight from the box. And I find it easy to condition, by hand, without the use of any mechanical devices. Polymer clays must be conditioned, by kneading for several minutes to soften and to distribute the plasticizers throughout the clay. But, I just pinch off the amount I need, and start rolling it between my hands. It's kind of a relaxing Zen thing, conditioning the clay, while my mind is wandering through the design process.
I am sure there are other advantages that I have forgotten to mention. So, feel free to leave your comments.
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