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1. The original sculpture is created through extensive research. Many hours of changing and refining are required to get a finished work in clay or wax. This can and often does takes months of work.
2. Flexible molds must be made of the original. This is done by placing a layer of clay around the original sculpture. A plaster support mold is made around this layer of clay. Then the plaster shell and clay are removed. When the plaster shell is replaced around the sculpture without the clay, the de-aired rubber can then be poured into the area that used to be filled with clay. This rubber is left to cure for a day, then cut open to remove the original sculpture. It is cleaned, then put together with the plaster support mold around it. Now this rubber mold is ready to be poured with wax to recreate the original sculpture. (A bronze such as "Lady Logger" is made with eight of these molds.)
3. Wax is melted in a pot to about 190 degrees, and is then poured into the mold, left for one or two minutes and then poured out. After a cooling period, the hollow wax duplicate can be removed. Any sculpture cast in bronze that is over one inch thick must be cast hollow. Thicker pieces cast solid will distort badly as the hot metal cools.
4. The wax reproduction at this point is chased (flaws, pinholes, etc. are touched up). It is then cut apart or has windows cut into it to insure thorough drying of the slurry, the ceramic shell mixture that is later applied.
5. The wax sculpture and its parts (cutouts, base, etc.) are fitted to a wax tree. The tree is a network of sprues and vents (wax limbs and branches) to channel the metal flow and eliminate air pockets.
6. This vented sculpture is then invested (dipped) in ceramic shell slurry. Sand is applied to the slurry. It is then left to dry in a temperature and humidity controlled room. This process of applying slurry and sand is repeated 8 to 10 times to build shell thickness.
7. The slurry covered wax figure is then placed in a burnout furnace and fired to 1800 degrees. This hardens the ceramic shell and melts and burns out the wax.
8. Bronze is melted in another furnace to about 2000 degrees. The hot ceramic mold is then placed in a sand box. The molten metal is poured in, filling the mold and its sprues and vents.
9. When the metal cools, the ceramic shell is chipped and sandblasted away. Then the metal sprues and vents are cut away.
10. Next, the bronze figure is chased. This involves chiseling off slag, small pieces of unwanted bronze. The pieces that were cut apart in wax are now welded back together with a tig-welder. Any bad spots are then welded, ground and tooled with high RPM air tools. The bronze base is leveled, drilled and threaded for mounting. For some sculptures, smaller hand made parts such as ropes and reins are attached with silver solder. Now a final sandblasting is done.
11. The bronze is given a patina (or colors) with mild chemicals by a pouring, dipping or brushing process. Heated with a torch, the chemicals cause the metal to change color. This coloring can enhance the design if it is skillfully done. An artist may choose to use different patinas to change the look of a bronze in the same edition.
12. The color is sealed by applying wax to a warm bronze with a brush and torch. After the piece cools, it is polished and mounted on a base that compliments the sculpture.
Note: For each and every duplicate casting produced, a new wax model is poured (step number 3) and the whole procedure must be repeated. Weeks of work are involved in each reproduction. Each is an original made from its own wax model. No two are exactly alike.
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