The Original Lost Wax Casting Process

The following is the step by step process of the “Lost Wax Casting” method. After reviewing this process, which normally takes approximately 3  to 4 weeks to complete a single sculpture. There is a lot of time and labor involved in each piece, each bronze is hand finished once in wax and then again in metal. It takes very skilled artists to complete this process, there is a great misconception that bronze is just poured into one mold and then you have a product this is the furthest from the truth. To learn more about this in depth process please read below.

Please Note: There are those that claim 22 to 30 steps in the lost wax casting process, this process can be broken down into over a 100 steps if you want to get technical about it. We try to keep simple and easy to follow.

STEP 1 Making the Mold: This step is by far the most critical. All the detail which appears on the sculpture must be captured in the mold. The mold (depending on the size of the sculpture) is cut into sections for casting.

STEP 2 Making the Wax Casting: Molten wax is poured into the mold to form layers of wax. This wax model is an exact duplicate of the original casting.

STEP 3 Chasing the Wax: The wax is pulled from the mold and hand chased (re-detailed) by a skilled artisan. Although the artist reproduces the original artwork, each piece may slightly differ from the next.

STEP 4 Spruing: Wax rods (gates) and pouring cup are attached to the wax casting in just the right positions. This will assure a full pour.

STEP 5 Casting the Ceramic Mold (Investment Casting): In a temperature controlled climate of 72 degrees Fahrenheit, the wax casting is dipped into Investment liquid several times. On the first dip a fine powder is applied. On the next dip of course, ceramic sand will be applied. This step is repeated several times, each increasing the coarseness of the material to create the ceramic mold. Between each dip, the ceramic layer must cure (dry) before another layer can be applied.

STEP 6 Burn-Out: The ceramic shell is placed in a kiln and fired. The shell bakes and the wax is melted (lost) from the shell. This creates a hollow ceramic shell mold. Thus the term “Lost Wax.”

STEP 7 Casting: The ceramic shell (mold) is removed from the kiln and immediately the molten bronze is poured into the shell. At the time of pouring, the bronze is 2100 degrees Fahrenheit.

STEP 8 Break-Out: After the casting has cooled several hours, the shell is carefully broken away leaving the unfinished bronze.

STEP 9 Sandblasting: Any fragments of the ceramic shell are removed by sandblasting. The sculpture is also carefully inspected at this point.

STEP 10 Assembly: At this time all the pieces of the sculpture are welded together by our skilled craftsman.

STEP 11 Chasing: All the weld marks are chased and re-detailed.

STEP 12 Glass Beading: This is similar to sandblasting. The glass is extremely fine to ensure an even bronze finish.

STEP 13 Polish: The raw bronze sculpture is now hand polished in preparation for the patina.