The Lost Wax Process

The oldest bronzes were cast of solid bronze; the weight was formidable.  Sometimes bronze was beaten into a thin sheet and then pounded into shape over a wood carving.  The use of sand molds was another process.  This "sand casting" as it's called is still in use today.  However, it is the "lost-wax" process that became the most common method of casting bronze with countless bronze sculptures since antiquities being made using this "lost-wax" process.  A process that is still commonly used to make modern bronzes sculptures.

The "lost-wax" process (also known as "investment casting" or by its French name "cire perdue") is a casting method that allows for tremendous precision and accuracy in its reproduction of the artist's original work.  Most sculptors use clay to create their original.  Then it's off to the foundry.

The foundry is where the "lost-wax" process actually takes place.  The foundry examines the artist's sculpture to determine how best to go about creating the cast.  Many clay sculptures, due to their complexity, must be "cut" into several pieces so each piece can be cast separately.  Once the foundry has determined how best to go about casting the sculpture, it is cut into pieces, if necessary, and then:

• The foundry creates a silicone mold of the clay sculpture (or each piece of the sculpture).

• The silicone mold is then covered with fiberglass and plaster to make a sturdy shell.

• The inside of this silicone mold is then lubricated to prevent the wax from sticking.

• Hot wax is then poured into the mold and spread out evenly throughout.  This step is repeated at least three times to create a thick, hollow wax image of the original sculpture.

• Once the wax has cooled, the rubber mold is removed to reveal the wax image.  Voelkel Designs Studio insists on smoothing out or repairing any imperfections, such as air bubbles, because the wax is now an exact antecedent or prototype of the finished bronze.

• The wax image is then dipped in a ceramic slurry once a day for eight days to build up a thick shell both inside and outside the hollow wax image.

• This ceramic shell is then placed in a kiln at 1,600 degrees to harden.  Of course as it's heated, the wax melts away, leaving an empty ceramic mold (thus the name "lost-wax").

• Molten bronze, heated to 2,200 degrees, is then poured into the mold to fill in the space where the wax had been.

• Once the bronze has cooled, the shell is chiseled away to reveal the bronze sculpture.

After the casting is complete, the pieces that were cast separately must be welded back together.  The welded seams are ground down and smoothed out to the artist's approval.  

The lost wax process produces extremely accurate results but as you have just read, it is a process that requires many hours of work by skilled artisans to complete.

Voelkel Designs Studio

Wine Related Bronze Sculpture

Call us at:

(707) 433-0215

Our Studio is located at:

526 Johnson Street

Healdsburg, CA 95448

Mail us at:

P.O. Box 186, Healdsburg, CA 95448