PRODUCT

How Is It Made ?

The “Lost Wax” Process

What gives bronze art value beyond that of a “souvenir” that ends up in a
closet? There are many reasons including cost of materials (bronze,
silicone for molds, tools, ovens, etc.) The main reason is that there are
very few people trained in the tedious process, practiced by the ancient
Greeks and Romans.

Bronze sculpture is not easy to make and there are many time consuming,
difficult steps involved. In a world of hi-tech mass production, bronze
casting remains essentially unchanged. Each of our genuine bronze castings
is in reality an “original” and the following explains why. These are the
basic steps involved in creating a bronze Sculpture using the classic “cire
perdue” (lost wax) process:

• artist’s original model
• silicone mold of the model
• create lost wax mold
• bronze casting
• clean mold from casting
• grind, rasp and file bronze
• assemble pieces by welding
• file and finish assembled piece
• polishing
• application of patina

All bronze pieces are cast from a wax model regardless of the original
material the model was sculpted. A silicone mold is made from the artist’s
finished piece, and a hollow wax cast is drawn from this mold. The wax is
then repaired, re-worked and finished to the sculptor’s specifications.
Prior to creating a ceramic shell (explained below), vents are attached
within the wax model. These vents are necessary in difficult areas where
gas may accumulate such as hips, limbs, and neck. The vents allow the gas
to escape when the molten bronze is poured and will prevent air pockets
from forming and exploding the ceramic shell. The ceramic shell is one of
the few materials the can withstand the heat of the molten metal.

When the wax cast is hardened and the vents are in place a ceramic shell
is formed over the wax. This shell is made by dipping the wax into a
slurry, coating it with sand, drying and repeating the process up to 14
times. A core consisting of plaster, ground brick and water is poured into
the interior of the wax mold. After the ceramic shell and core have set,
the mold is fired in an oven, the wax is melted and the ceramic shell is
left intact. This process is known in French as “cire perdue” (lost wax).
Molten bronze is now poured into the cavity left by the melted wax. When
the bronze is cooled, the shell is chipped away using a hammer and chisel.

The bronze must now be repaired and finished. This step is called
“chasing” and it is a difficult process because the metal is involved. Any
imperfection such as air pockets of pits must be brazed with bronze rod,
as in welding. All seams and spurs must be removed by grinding, rasping
and, finally, sanding. The next step is to chase or hammer the vents from
the mold using special tools. The natural bronze has a dull finish. after
final finishing, a patina is applied which may be left matte of polished.
Chemicals, pigments, heat, safety equipment and a lot of experience are
involved. In addition, since bronze comes in a variety of alloys, the
patina requires different chemicals and techniques.

When shopping for bronze art work, beware of terms such as “cold cast” or
“bonded bronze.” These are misleading names given to plastic figurines. If
you are unsure of the authenticity of an item that you see elsewhere, feel
free to call us at 1-800-321-8618 for an honest and professional opinion.