Metal Working: How Is A Copper Sculpture Made?

A brief history of copper sculpture in America as well as an introduction to building and design.

The center for the creation of hammered copper sculpture in the America's is in Santa Clara del Cobre, Mexico. Beautiful copper art is created by family workshops using century-old methods. The history of copper sculpture goes back to the Purepecha Indians of Central Mexico. They produced domestic implements and weapons by hammering copper ingots on stone anvils.

The village of Santa Clara del Cobre was founded by the Spanish in the mid 1500's in order to exploit the use of the ore, which lay near the surface. They constructed a large forge and Santa Clara became the center of copper smelting in New Spain. Copper production and products peaked in Mexico in the second half of the 19th century. In post World War II Europe, American sculpture James Metcalf became frustrated with the current commercial system and looked for an alternative. When he settled in Santa Clara in the late 60's he introduced new ideas on technique and design to the coppersmiths. He introduced classical Greek and Roman designs as well as thick edged vases. In 1968 the town was commissioned to do the Olympic Torch for the Games in Mexico City.

To create beautiful sculptures the coppersmiths use a technique that is hundreds of years old. Pure copper is repeatedly heated and hammered into a vase, bowl, pot or other desired shape. The copper is smelted in a coal-lined hole. If copper is cold it can be easily split with a hammer. An open forge can heat the copper to over 2,000 degrees. By using two horizontal bellows a draft of air intensifies the fire. As the metal is repeatedly heated it becomes malleable and is shaped by hand with hammers. By first forming a bucket, the copper can be formed into any desired object.



By using metal anvils of different shapes an object can be closed, creating new forms. It's possible to close the vessel and polish it from the outside, such as in the creation of jugs, vases and decorative centerpieces. The surface can be polished with a smooth faced hammer or can carry a design through the use of patterned faced hammers.

Quality work is distinctive from the thick edge of the vessel lips which comes from being made out of one piece of copper rather than a copper sheet. By using special anvils and hammers on the inside, a raised figure is created. Feet, handles or bands are not soldered or riveted on but formed from the piece.

Modern day copper sculpting is much different than that from historic Mexico. Today's tools are more advanced and more diverse. Today pieces of copper art, especially the larger structures, tend to be made out of more than one piece of copper sheeting. The pieces of copper are tig welded together, enabling a sculpture to go as large as he desires. Tig welding is the use of Tungsten gas and filler rod to join two pieces of metal together. As with the older form of coppersmithing, all work starts with a general convex bowl shape.

Forming stakes are used with larger creations, allowing the sculptor to still have access to the inside to do reforming as necessary. As the form is created gaps can be filled in using a welding rod. The sculptor will generally have a paper pattern that is a guide to the finished product. This is a hand drawn piece that may change as the process continues. It also acts as a guide when the artist is cutting pieces from copper sheets, using either Beverly shears, which are long handles, finely sharpened shears, or a plasma torch. Beverly shears are used to cut compound curves but if the curve is very complex a plasma torch is used instead. In place of a plasma torch, a band saw can also be used to cut complex curves.

Once the sculptor has reached the point of closing the piece of art, if so desired, no further adjustments can be made. Hammers are used to planish the form, which is a process used to smooth out the surface. Irregularities are worked out of the metal at this point. To planish, a direct strike is not used. Instead a rocking motion is used when striking the copper depending on whether the sculptor wants to lift or sink the metal. After the piece is finished all that is left is to add a finish.

There are four different finishes that can be applied to the sculpture. The natural color of copper can range from chocolate brown, wine red, to bright copper and black streaks. The color variation and contrast is created by the coppersmith in his forge and can be large or small. It varies from piece to piece with no two the same. Through buffing the coppersmith can remove the natural patina leaving a bright finish behind. If the artist chooses, after being polished to a bright finish, silver decoration can be added. This is called silver plating. First a design is created on the surface then the piece is dipped into an electrically charged bath. This process fuses the two metals together. If the item has a polished surface it requires regular polishing in order to keep a shiny appearance.

To remove oxide from the finished piece, an easy and safe way is the use of white vinegar and a rough sponge pad. After that step piece is washed with clear running water and after drying, any touch could leave behind oily finger and handprints. Copper pieces that are created for decoration generally have been treated with a clear lacquer coating. Maintenance is easy as it requires no polishing, just a simple dusting.

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