Direct lost-wax casting technique
A bronze sculpture is obtained from an original in clay, wax, plaster, stone or any other material from which a silicon mold is made. This mold is used to make a wax print.
The basic technique has not changed through the centuries.
Liquid wax is poured into the mold after having put a first layer by brush to allow a perfect print of all the details. This is left to solidify before carefully removed. All imperfections are being taken care of such as joints and others. A network of rods and a pouring cub are fitted onto the wax positive to allow the distribution of the liquid bronze in an equal and rapid way everywhere as well as the evacuation of gaz.
A layer of a refractory mixture of plaster and chamotte in a thickness of 10 cm is applied and the interior filled with the same mixture. The core is held in place by nails running through the wax sculpture. This refractory mold can withstand the necessary heat of 700 degrees to melt the wax.
This new mold is put in a waxing oven for 3 to 7 days depending on the size of the work, leaving a gap of 3 to 5 mm, that too depending on the size of the sculpture.
Bronze ingots are molted at 1200 degrees. This shell is filled with liquid bronze and left to cool. A few hours later the shell is removed using a hammer and a high power water blaster, revealing the cast bronze. There remains the chasing to be done to eliminate all traces of the rods. A long work of craftsmanship.
The bronze is finished by applying a patina using chemicals and heat to achieve a desired finish.