How your bronze pig was made
This bronze pig was made using the traditional method of casting bronze; it’s called the ‘Lost Wax Process’.
It’s a long and labour intensive process but the results are certainly worth it.
So, this is how your bronze pig was made step by step;
First of all the pig was created as a clay model.
A mould of the clay sculpture was then made using plaster with a latex coating to preserve the details.
Molten wax was then poured into the mould and swished around until an even coating covered the entire inner surface. This was done in several layers until the desired thickness was reached.
This new, hollow wax copy of the original pig was then removed from the mould.
The hollow wax copy was then ‘chased’. This was done using a heated metal tool to remove any marks or imperfections.
The wax copy of the pig was then ‘sprued’ with a tree-like structure of wax. This was done to create paths for molten bronze to flow as well as let air escape.
The ‘sprued’ wax copy of the pig was dipped into a ceramic slurry, then into a mixture of powdered clay and sand. Once dry, the process was continually repeated until a half-inch thick layer covered the surface of the pig.
The pig was then placed in a kiln to harden the ceramic coating into a shell. The heat also made the wax melt so it could run out.
The ceramic shell was then allowed to cool. It was also tested to see if water would flow through the feeder and vent tubes as necessary.
The ceramic shell was then reheated in the kiln and filled with sand. Bronze was then poured carefully into the shell. The bronze-filled pig was then left to cool.
The ceramic shell of the pig was carefully chipped away, releasing the bronze underneath.
The pig then underwent final inspection! Any pits left by air bubbles in the molten bronze were filled and the stubs of spruing filed down and polished.
The bronze pig was then coloured using chemicals. This colouring is called patina and is normally green, black, brown or gold. Certain chemicals will produce certain predictable colours when they are sprayed on the bronze and then heated up.
Finally, a coating of wax was applied to protect the surface. The Result… your perfect bronze pig!