How do you make a bronze sculpture

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The process beginswith the arist's original piece sculpted in clay

Making the Mold

ALL DETAILS OF THE SCULPTURE ARE CAPTURED IN THE
MOLD

WAX CASTING
MOLTEN WAX IS POURED INTO THE MOLD. IT IS THE EXACT DUPLICATE OF THE ORIGINAL.

CHASING THE WAX
WAX IS PULLED FROM THE MOLD AND HAND CHASED (RE-DETAILED TO MATCH THE ORIGINAL

SPRUNG
WAX RODS AND A POURING CUP ARE ATTACHED TO ALLOW FOR GASES TO ESCAPE AND TO ASSURE A FULL POUR.

INVESTMENT CASTING
THE WAX CASTING IS DIPPED INTO INVESTMENT LIQUID 10 TIMES IN A TEMPERATURE CONTROLLED CLIMATE
FINE POWDER IS APPLIED ON THE FIRST DIP AND CERAMIC SAND ON THE OTHERS THIS PROCESS CREATES THE CERAMIC MOLD.

BURN-OUT
THE CERAMIC SHELL IS PLACED IN A KILN AND FIRED AT 2000 DEGREES. THE WAX MELTS AND THIS CREATES A HOLLOW CERAMIC MOLD.

CASTING
THE CERAMIC SHELL IS REMOVED FROM THE KILN AND THE MOLTEN BRONZE IS POURED INTO THE SHELL AT 2100 DEGREES.

ROVING THE CERAMIC SHELL
THE CASTING IS COOLED FOR SEVERAL HOURS AND THE SHELL IS BROKEN AWAY.

SANDBLASTING & ASSEMBLY
SANDBLASTING REMOVES ANY FRAGMENTS OF THE CERAMIC SHELL. PIECES OF THE SCULPTURE ARE WELDED TOGETHER
IN THE CASE OF A MONUMENTAL SCULPTURE OR ANY SCULPTURE CAST IN MORE THAN ONE PIECE, THE SECTIONS ARE ASSEMBLED AT THIS TIME

CHASING
7 GLASS BEADING
WELD MARKS ARE CHASED, REDETAILED AND SANDED. SCULPTURE IS BLASTED WITH FINE GLASS BEADS

FINAL PROCESS PATINA
THE PIECE IS HEATED AND A PATINA CHEMICAL IS APPLIED BY HAND FOR COLORIZATION

WAXING
WAX IS APPLIED BY HAND WITH HEAT TO PROTECT THE PIECE

American Vs Asian Bronze

One of the questions I receive is why the bronze art of the Asian countries looks different. And why is it so much less? The answer is: the metal, the art, and the artist.

Consider this the quality of the bronze metal. Here in the great USA we have a minimum standard for the bronze that we cast of at least 90% copper. In very high end bronze pieces 98% copper.
So let's explore why this semi-precious metal is so important to bronze sculptures.

Most important, is the copper content in bronze this is the property that gives the sculpture the resistance to corrosion. This is most important if the sculpture is outdoors. Over time a bronze sculpture with low copper content (55% in imported sculptures) the metal developes a white flaky material on the surface. Some will also develop rust spots with is an indication of iron compounds in the metal.

Any bronze sculpture with a low copper content does not accept a quality patina (in its raw state, bronze is gold in color. 55% imported bronze is silver in color. When the sculpture is cast and assembled, the artist applying the chemicals that react with the copper in the bronze it literally changes the surface color of the bronze. Different chemicals result in different colors. The most common patina is with liver of sulfur that results in a brown patina.) The sculptures found of high quality the patination process is done by hand by skilled artists that have years of experience with chemicals and how they react best to the metal. To achieve the best effect for the piece. In the sculture that has the low copper the piece of art is dipped into a patina solution. Resulting in a uniform, lifeless color. This type of patination will fade and come off over time.

A point to ponder are these people being paid slave wages is the workplace safe? The bronze foundry is an industrial environment with extremely heavy machinery and molten bronze.

When purchasing a bronze original sculpture from any artist the process is expensive. Its an original piece. It must be sculpted, moulded, chased, bronzed and based. Reproductions have previously met all these processes. Remember an original is that an original.

Asian sculpture is purchased and enjoyed all the time they are afforable. Proceed with caution. Consider your design and your budget.

Why to people buy bronze art from China? Is it the price? Perhaps we don't know the differences in the bronze. That to follow