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u Pictorial view of how a sculpture is bronzed u Some useful facts u How to contact the foundry

How a sculpture is bronzed

  The sculpture is first created in clay over a wire frame and supported by an adjustable stand. The clay is kept moist until the mould is taken.
     
The sculpture is 'laid up' in clay to create a seam for the mould.
     
Rubber (silicon) is applied to the first half of the sculpture. When cured, a plaster case is made over the rubber. The clay wall is then removed and the process repeated for the other side. In more complex sculptures this can require three or four (or more) sections.
     
The mould is removed, leaving the original intact.
     
The mould is then painted up with hot wax to capture the surface detail.
     
The seamline surfaces of the mould are cleaned off and the mould put back together. It is then filled to the top with cooler molten wax.
     
After a few moments the wax (still molten) is slushed back out into the bucket.
     
The mould is then opened to reveal a hollow wax casting of the work.
   
The wax is now worked and the seam line tooled and made good.
     
Runners and risers and cup, all made in wax, are now applied. These are for the venting and pouring of the bronze.
     
The wax has been 'cored' (filled with a solid mixture of plaster / grog supported by steel pins pushed through the wax. It is now covered in a ceramic shell. Several coats are built up over a few days.
     
The ceramic shells are placed in a kiln for the wax to be melted out, and are then pre-heated in preparation for casting.
     
The bronze is melted in a seperate furnace in a clay / graphite cruicible to a temperature of approximately 1200 deg.C. It is then poured into the ceramic shell which is buried in sand for support.
     
Once cool, the ceramic shell is broken away to reveal the casting.
     
All the ceramic is removed, the bronze runners / risers are cut off and the surface is prepared for finishing. The core is removed and the pins pulled out.
     
Where the runners / risers made contact with the sculpture the chaser works the detail back into the bronze.
     
The chasing complete, the surface is lightly brought to a clean finish in preparation for the 'patina'.
     
The patina or colour is applied using heat and chemicals, and is sealed for a high finish with a neutral wax.
     
The finished sculpture is packed and ready for shipment.
     
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