Lost Wax Process

The first step in the process is the creation of the wax model for the chosen figure.  The wax used is beeswax mixed with a local tree resin and coconut oil. A harder mixture, less oil, is used for the main body parts and a softer wax, more oil, is used for the small pieces like jewelry and other trim pieces.  A charcoal brazer(Shown in lower middle Picture) is used to heat shaping implements and small pieces of wax during the modeling process.  In the past all of these statues were poured in solid bronze but in present times pieces over 16 inches tall or so are made hollow as allowed in the body shape.  Typically the torso, head, legs and arms are the hollow areas.  This saves bronze material and also allows for a lighter weight statue economizing on shipping costs. The hollow mold is filled with a clay plaster mixture which can be poured, usually through on opening at the top of the head which is closed off after filling.  The picture in the lower left shows the copper pins which anchor the plaster/clay fill to the clay/plaster exterior mold once the wax is melted out leaving  an approximately 7 millimeter thick skin of the statue which the molten bronze will fill creating the finished form.  All statues can be poured solid based on discussion at the time of order.

 When the wax model is complete it is laid on a flat surface and the first layer of plaster is applied to the front of the statue. When this coat is adequately dried reinforcing steel is bent and laid on the mold strengthening the perimeter and crisscrossing the interior based on the shape of the statue. When the steel is in place a second coat of plaster is applied and allowed to dry to a hard state. The statue mold is then turned over and the wax modeler does final touch up modeling to the figure and trims the plaster to assure a clean and even void-less seem between the 2 sides of the mold.  When 2 layers of plaster and reinforcing steel have been applied the mold is then wrapped tightly with 4 millimeter wire and a final coat of plaster is applied. The plaster mold mixture is approximately 3 parts plaster to one-part rough sand and one part fine sand. This applies to statues up to 25 kg in weight, over that weight and a clay mold is made of River bottom natural clay mined from specific areas in the region (see picture above of base for a large Vishnu statue). Using plaster speeds up the process significantly since it hardens enough to apply subsequent coats within 2 hours depending on outside air temperature.  The clay mold above took over 3 weeks from the time the wax modeling was completed and the first layer of clay, reinforcing steel and subsequent layers were applied and allowed to dry completely.

When the molding is completed and the plaster or clay statue mold is adequately dried, the Losing of the Wax process is begun based on the casting schedule.  Typically, the Losing/melting of the Wax, the oven baking of the empty mold and the casting all occur in a maximum 30 hour period. As shown in the pictures the molds are placed on a metal rack that keeps the wax separate from the fire.  This allows the fire to be able to be controlled such that the wax itself does not catch fire and it can be saved and used again after filtering. The Losing/melting of the Wax process as shown in the pictures above takes about 8 hours from the initial setup to the time the fire is out.  After the wax is lost, the statue molds are tightly packed with the top open port again facing downward to allow any residual wax to drain and firewood is packed in below and around the molds.  A brick oven, complete with a mud and straw top is then constructed around the stack of molds and wood and a fire is again set under the molds and they are baked for another 8-10 hours.  This baking not only removes any residual wax, but more importantly raises the temperature of the mold so that when the bronze is poured in from the top open port it flows freely to all parts of the statue and does not harden by encountering a lower temperature part of the mold which might block the free flow of bronze into the entire negative imprint of the statue wax.

As soon as the furnace is started and the bronze metal is beginning to heat up to the 1000 degrees Celsius(1820 degrees Fahrenheit). High quality scrap bronze, pulleys and other tooled high precision machine part is feed into the crucible sitting in the forced air forge.  The final proportion a type of copper, tin, and zinc is some-where in the proportion of 80%-Copper,14%-Tin and 6%-Zinc but actual combinations are a trade secret. If you were  to request Panchaloha bronze with gold and silver the proportion per kg would need to be specified by the buyer. The baked statue molds are unpacked from the oven and buried in the casting area adjacent to the forge.  This maintains the mold temperature and stabilizes the mold when the molten bronze is poured in. The pouring process is a high energy swift series of movements practiced over many years. A majority of castings are done at night to leave the freshly poured statues to slowly cool and harden through the early morning.

The next day after casting, the molds are unearthed from the casting area and the plaster, reinforcing steel and wire is carefully removed. A small scraper is used to get to the basic form of the statue and then a soft wire brush on a drill is used to clean the statue for the majority of the basic finishing is done with flat files and scraper (see picture).   This process alone for an 18” statue involves many man hours of practiced filing and scraping before it is ready to go the Master for hand chiseling and detail work.  The Master will return the statue to the Journeyman statue craftsman for specified hand work as he adds the details to the Crown, belts, sashes and general finish.  The Journeyman craftsman  will also be involved in the attachment to the base and the patina work.