This is an example of what it takes to make a mold. As you can see it's a multiple step process.

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Step 1. SCULPTING

First I sculpt figurine in oil-based clay. Hardness of clay is a mete of preferences. Harder clay does keep details better but it's harder to work with. So, I try to make it as easy as I can without sacrificing quality. During sculpting process I always have to keep in mind where the seem-line will go. To make pieces more three dimensional sometimes I use an "add-ons". Like on this cherub figurine I decided to make a dove an add-on. All that needs to be decided during sculpting stage.

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Step 2. MAKING A WASTE MOLD

I use oil-based clay, preferably of a different color to clay around my figurine, along the seem-line. Add-on piece treated the same way but separately. After that I mix plaster and brush it on my figurine. When I build up layer about 1/4" I usually add extra plaster by hand. When plaster is set I remove clay from seem-line and make keys. I usually use hand drill for it. Then I apply thing layer of vaseline on the service of my waste mold and repeat process from other side.

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Step 3. CASTING FIGURINE IN WAX

When plaster does set up I open waste-mold and remove clay figure from it. Then go over it and re-detail waste-mold as much as I can. When I am done waste-mold look like that - see (Fig 5). Then I submerge it under water for 15-20 minutes to saturate plaster with water (Fig 6). That will prevent hot wax go in to pores and stick to my mold. Then I remove remaining water and strap it tight see (Fig 7). By that time I have a pot with melted wax ready and pour it into waste mold.

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Step 4. REDETAILING SCULPTURE IN WAX

After I get my sculpture cast in wax, I go over it re-detailing it again. Wax can hold details much better then clay can. That allows me to make much finer details. "Ad-ons" are attached using plaster. That allows me to key attachment in to piece exactly.

Step 5. MAKING A MASTER MOLD

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Step 6. SHAPING A MASTER MOLD

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