Bronze casting has been a traditional form of art in Myanmar for centuries. In historical times, bronze was used to make musical instruments and essential household goods as well as religiously significant items. Today, Mandalay remains to be the home of many workshops where the countless bronze Buddha images you see around the country are created using techniques little changed by modernity. The first step of the process is to cast from clay an inner core in the same shape as the final desired image. For sculptures more than a meter high, the inner core is often reinforced under the surface by bands of iron. Once the core is dry, the wax mixture is prepared.
The mixture is made of 90% beeswax and 10% resin called indwe. To maintain plasticity some splashes of oil are added. The mixture is melted and poured into a water basin of water, where it solidifies in thickness to that of the metal. The wax is then applied around the clay core. Finer details are cut or etched into the wax surface, while piece of wax in various designs may be added at this stage to create surface relief .After the wax image is coated with fine red clay and powdered paddy husk, care is taken to make sure that every crevice is completely covered.
The outer mold is then created with a heavier mixture of clay, sand, and paddy husk. To hold it in place some thin iron rods are inserted into the wax to the clay core. They later act as an escape for the wax when it is replaced by molten bronze, it’s then left to dry.For the casting process, metal is smelted in a crucible. For brass the mixture is about 8 parts of zinc and 10 parts of copper. For bronze the ratio is 4 parts of tin with 6 parts of copper.The mould is placed upside-down in a wooden framework and suspended over a hole. The clay mould is heated, causing it to become a hard substance. This is turn liquefies the wax which runs out of the mold via some of the escape holes. Molten metal is then poured in. The pouring of metal for a large statue can take quite a while and requires a high level of expertise and experience. After cooling for about three days the outer mold is broken off and removed. Any excess metal and surface roughness is removed and the sculpture is smoothed over.