The Lost Wax Process
All our bronze statues are cast 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.
We work with bronze foundries in Asia who we know and trust. Our relationship with them spans 25 years. They understand the quality and service we desire.
Here’s a very quick synopsis of how each bronze statue is made using the lost wax process. It can take about 4 weeks to create a large statue.
- First of all a clay model of the animal/fountain is sculpted.
- A silicone rubber and plaster mould is then made of the clay model.
- The silicone rubber mould is used to cast a hollow wax copy of the sculpture. This is done by coating the mould with a thin layer of wax normally 3 to 4mm in thickness.
- Once the wax hardens the silicone is removed and you’re left with a hollow wax replica of the original sculpture. A hole is cut into the replica and it’s filled with a special plaster mix (resistant to high temperatures).
- A network of wax rods (runners and risers) are then attached to the surface which become channels for the bronze to flow and gases to escape.
- A ceramic shell is then made by dipping the wax replica into the special plaster mix. This is done several times to build up a thick layer.
- The mould is then placed in a hot kiln to harden. The heat also allows the wax to melt and run away (lost wax).
- Molten bronze is poured into the empty cavity left by the melted wax.
- It is left to cool and then the outer ceramic shell is carefully chipped away, releasing the bronze underneath.
- Any pits left by air bubbles are filled and imperfections filed down. The runners and risers are cut away and the statue is polished.
- The statue is coloured using hot chemicals. This colouring is called a patina. Here are some sample patinas.
- Finally, a coating of wax is applied to protect the surface.