A Narration of Austin Weishel of Honorable Sculptures in
The Building of the National Fire Dog Monument.
From the beginning Austin starts every sculpture off by using foam and clay that will never dry. He then continues to sculpt and shaped the clay until it is perfect. For a life size figure it will take any where 1,000 to 1,500 hours to sculpt.
The Rubber Molds
When the clay design is complete, it is off to the mold process. The mold is made of silicone rubber, applied initially to just one half of the sculpture (or
section of sculpture, if the piece is large). Once the initial application has dried, the same material is applied to the other half, creating two separate pieces that can be joined together after each has
been coated with fiberglass or plaster to retain it’s shape and lend rigidity. These molds are the only pieces
that can be re-used in the casting process.
The Wax Positive
After molding the sculpture the mold is then applied with a thin wax coating approximately 1/4” thick. Once the wax has cooled and hardened, the outer mold is removed, revealing a hollow wax twin of the original sculpture. This wax duplicate is carefully checked and “touched up” to remove any scratches, seam lines, or other flaws.
The Ceramic Shell Casting
Through a process referred to as gating, a series of tubes are attached to the wax replica which will eventually allow the liquid bronze to flow to all parts of the casting. Now the gated wax piece is dipped in a liquid ceramic silica/sand compound, completely covering it inside and out. It will be dipped an additional 6 to 12 times until the desired shell thickness is achieved. Once this shell is dried, it is placed in an autoclave to melt away–or lose–the wax; hence the name “lost-wax”.
The Bronze is then heated to approximately 2000ºF before the molten metal is poured into the ceramic shell, where it cools rapidly. The ceramic shell and gating can now be completely removed with a hammer and chisel, revealing the bronze outcome.
If sections of a larger piece were cast separately, they are now welded back together to their original form.
Pieces that are casted are now welded back together to their original form.