Simulate Metal with Cold Casting
Metal statues and sculptures are traditional materials. The beauty of the metal and the patina is especially attractive and pleasing. But, actually casting a metal figure from molten metal in a foundry proves expensive, time consuming and relatively dangerous as well.
And that's why we turn to the simpler and cheaper technique of cold casting. This is where a fine metal powder is mixed with an appropriate binder to simulate a metallic finish exactly like an original metal casting!
The process of cold casting is quite easy and fast as well. Any metal powder from bronze, brass, aluminum, nickel or copper to even silver can be used depending on the effect desired. The cold casting powder is nothing but the metal that has been ground into a fine powder. Generally, metal powder with fine grade of 325-mesh is considered the correct fineness for cold casting.
The cold casting powder is mixed with a casting medium, either with polyester resin, urethane resin, polyurethane resin, epoxy, gypsum cement or other binders (usually in a 1:2 ratio). They should be mixed well until the mixture is thick and creamy. Then the mixture is dusted, slushed, brushed, spread or sprayed on the mold - either on the inside or outside surface - to create a thin and uniform coating all over the mold. But this will give a hollow finished casting. It still needs the weight and stability of a solid metal sculpture so as to look and feel like the original. For this purpose, it is back filled with resin, foam or fiberglass. Iron balls, lead beads, steel shots, sand or calcium carbonate can be added to get the desired weight.
After proper curing and demolding, the surface of the cold casting must be lightly abraded or burnished with either medium or fine steel wool to remove the tiny binder on the surface and expose the pure filler metal powder beneath. Only then will the desired metal shine and luster be attained. This metal surface will tend to oxidize and can even be sealed with a coat of acrylic or clear gloss spray. Alternatively, patina paints can also be used to imitate a variety of artistic effects. Some artists choose to highlight the surface with brown paint or even black shoe polish to get an added depth and dimension to the casting.
The final result is a lovely cold cast that has the exact look and appeal of a hot metal casting! Similarly, limestone or marble powder can be used to achieve a stone finish, porcelain powder for a ceramic finish on cornices and appliqués and pecan shell (wood) flour being for that attractive wood effect on furniture and moldings
Therefore, cold casting emerges as a useful, simple and low cost option that even permits mass production of metal, wood or stone sculptures at a much lower cost!
And that's why we turn to the simpler and cheaper technique of cold casting. This is where a fine metal powder is mixed with an appropriate binder to simulate a metallic finish exactly like an original metal casting!
The process of cold casting is quite easy and fast as well. Any metal powder from bronze, brass, aluminum, nickel or copper to even silver can be used depending on the effect desired. The cold casting powder is nothing but the metal that has been ground into a fine powder. Generally, metal powder with fine grade of 325-mesh is considered the correct fineness for cold casting.
The cold casting powder is mixed with a casting medium, either with polyester resin, urethane resin, polyurethane resin, epoxy, gypsum cement or other binders (usually in a 1:2 ratio). They should be mixed well until the mixture is thick and creamy. Then the mixture is dusted, slushed, brushed, spread or sprayed on the mold - either on the inside or outside surface - to create a thin and uniform coating all over the mold. But this will give a hollow finished casting. It still needs the weight and stability of a solid metal sculpture so as to look and feel like the original. For this purpose, it is back filled with resin, foam or fiberglass. Iron balls, lead beads, steel shots, sand or calcium carbonate can be added to get the desired weight.
After proper curing and demolding, the surface of the cold casting must be lightly abraded or burnished with either medium or fine steel wool to remove the tiny binder on the surface and expose the pure filler metal powder beneath. Only then will the desired metal shine and luster be attained. This metal surface will tend to oxidize and can even be sealed with a coat of acrylic or clear gloss spray. Alternatively, patina paints can also be used to imitate a variety of artistic effects. Some artists choose to highlight the surface with brown paint or even black shoe polish to get an added depth and dimension to the casting.
The final result is a lovely cold cast that has the exact look and appeal of a hot metal casting! Similarly, limestone or marble powder can be used to achieve a stone finish, porcelain powder for a ceramic finish on cornices and appliqués and pecan shell (wood) flour being for that attractive wood effect on furniture and moldings
Therefore, cold casting emerges as a useful, simple and low cost option that even permits mass production of metal, wood or stone sculptures at a much lower cost!
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