Its divided into four distinct stages namely
1- Creation of the wax model
The first step in the process is to create a wax model .The model is an exact replica of what the finished bronze piece will look like .The Percentage of bee’s wax is greater giving the wax more of a golden coloration. Most or all of the work in the creation of the wax mold is done outdoors especially on the larger pieces .This makes our artists very dependent on the weather.
First the general shape of the model is produce in wax. Then a fire is used to heat a smooth metal file. The heated file is then moved up and down the wax piece to shaped the details of the model. In larger piece are done separately to maintain the integrity of the piece in the heat of India.
Once the various pieces are completed they are carefully assembled to form the final wax model. Using the flame of a lamp the connecting points are heated do that they can be melted together. With the artist’s finger, the arm joint with smoothed to fit with the torso and the torso smoothed to fit with the base .Once completed the wax model are placed into water to ensure that they do not loose shape in the Indian sunny climate.
2- stage Forming the Mold
Forming the Mold:-There are three steps required to make the actual mold that covers the wax figure for casting of the bronze statues ,The term “Mold” refers to the hollow clay from that will be filled with molten bronze to form the figure. In the first step ,White clay know as china clay’s is mixed with water to make a thin solution .This solution has a fine consistency which allows it to peak up the finer features of the was model. This solution has a fine consistency which allows it to pick up the finer features of the wax model .This solution is then painted onto each wax model using a paintbrush and then allowed to dry for two days .This process is repeated twice .For the second step a one to two centimeter pasty mixture is applied to the outside of the model by hand .Once the paste is dried . Holes are made at the bottom of the mold, which allow thin rods of wax to be attached to wax base of the statue. These thin rods serve as a passageway, they allow for the molten bronze to be poured into the mold and as an avenue for the displaced air to escape out of the mold.
For the third step, a third and final coating of rice husk, sand and clay is used to cover the entire surface of the piece. This is the final coating of the mold, applied to increase the thickness of the mold and to cover the nails, which were inserted in the previous step. Small, cup like reservoirs are formed above each nails to allow for the metal to be poured into the mold without spilling it.
Casting the Mold--3rd stage
In reality, kings, the wealthy, and temples were the only people and institutions with enough money to create true, five metal (panchaloha), bronze deities. The five metals were gold, silver, copper, brass and lead. For contemporary bronzes; copper, brass and lead are the three main ingredients. Copper contains small amounts of gold and silver so technically today’s bronzes are four metal bronzes. Copper is a necessary element in bronze because copper offers more malleability than other metals. This gives the sculptor a metal he can work with after the casting process to make the subtle alterations needed for a beautiful, finished piece.
As a general rule, approximately 220-260 pounds of bronze are cast at one time. The raw, unheated bronze is placed into egg shaped containers Once the molds and bronze containers are ready for firing, they are placed into the oven with the molds on the top and the containers on the bottom. The molds are positioned with the nalis facing downward allowing the wax to “burn out” after the oven is heated. Hence the name “lost wax method”.
To melt the bronze a temperature of at least 1800 degrees Fahrenheit is needed for approximately two to three hours .Once the firing is completed the molds are removed with the nails .facing upwards. Forceps are used to pick up the containers with the melted bronze so that the bronze can be poured into the molds through one of the nails.
Finishing the Piece-- 4th stage
After allowing the molds to cool for at least two hours, the bronze can be uncovered by chipping the layers of coating away. The entire statue is filed. There is almost always some small defect associated with the entire casting process. Air can be trapped in the mold creating a gap in the bronze or a piece can break off when the bronze is freed from the mold. Delicate reconstructive surgery takes place by heating up strips of metal to fill in the holes. This process is difficult and does not always succeed in solving the problem. For this reason a perfectly cast sculpture with no defects and perfect proportion is a prized piece since only masters of the art of bronze casting can achieve perfection in the entire process.
After being repaired and further filed down, the statue is sanded and buffed to remove any scratches and give the finished piece a shine. Care, precision, time and above all artistic ability are vital ingredients to practicing the lost wax method of bronze casting.
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