Casting is one of the earliest known forms of metal working. In its most basic form, it involves heating metal until it is molten and then pouring it into a mold. As the metal cools it takes the shape of the mold. Early castings were crude in finish with a lot of surface anomalies that required a great deal of machine work to get the desired quality of surface texture. Modern casting techniques produce very fine tolerances and the casting requires little or no finishing work. The artist who creates metal art castings needs to be both a foundry man and an artist. Bronze is one of the earliest alloys known to man and is made up of tin and copper. Being malleable, it becomes a liquid of low viscosity when melted and thus has the ability to fill even small crevices in a mold, allowing for the production of castings with fine detail. Although bronze castings are the most common, nearly any metal can be cast. The artist needs to know what kind of mold to use with what metal. And he needs to know how to melt metal. The casting process starts with the creation of the mold. The most common type is called the Lost Wax Casting method. Being simple to create and with the ability to create molds with fine detail, it is the artists’ favorite. First the artist creates a wax sculpture. This sculpture is then used to create a mold. Molds can be made from a variety of materials from sand to latex, depending on the amount of detail required. Latex is used when extremely fine detailing is involved since it forms a skin like coating on the sculpture and picks up even the minutest detail. The sculpture is then removed from the mold. Molten wax is then poured in the mold until the required thickness is achieved and the wax copy is then removed and any imperfections on the surface removed. A shell is then built around the copy using a mixture of sand and liquid silica. The shell is heated until the wax melts and runs out through a drain hole left in the shell.

Metal art castings may be of any size, from the smallest piece of gold jewelry to a huge cast statue to big to even fit indoors. The advantage of this type of metal art is the fine detail that can be produced. Modern metal melting techniques ensure that the molten metal that enters the mold is without imperfections and strong enough to securely hold a diamond (in the case of jewelry) or withstand the rigors of nature (in the case of garden sculptures).

This entry was posted on November 18, 2008 at 9:38 am and is filed under Arts & Crafts. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.