My ceramic sculptures are hand built from clay. The final sculpture is given a first (bisque) firing in my electric kiln. The fired piece is either coloured by hand with slips and glazes and refired several times in the electric kiln (such as Bella the Whippet) OR it is given a second firing in a raku kiln. The sculpture is removed from the raku kiln and immediately placed in a smoke chamber to achieve the final “smoked” finish which is illustrated by Elephant Calf and Baby Black Rhino.
Etchings are made on a metal plate (usually copper, sometimes zinc). Here is a very simple explanation of what can be a complex process. A weak solution of acid is used to “bite” (etch) marks into a metal plate (usually copper or zinc). Ink is rubbed onto the plate, most of the ink is rubbed off but some is held by the indentations on the plate. Dampened paper is placed over the plate and both are run through a roller press. The pressure applied by the press transfers the ink from the plate to the paper.
This printing process is very different from a large scale digital process. Each print is produced by hand from a hand inked plate. The plate needs to be inked up each time between each pass through the press. Every time the artist inks a plate, the final effect is slightly different. Usually a number of artist proofs are pulled from the plate while the artist is working out how to acheive the effect he/she wants. So a hand pulled etch is a unique print.
Bronzes (which are produced at a foundry) are made by the lost wax method. This method has been used to make bronzes for thousands of years. All bronzes are cast from some form of original or “master”, most usually constructed from clay, plasticine or wax.
First a mould is taken from the original. Today, this mould is usually made from silicon rubber, which is flexible and easy to use. Previously piece moulds were made from plaster. Molten wax is poured into the mould. The mould is moved and rotated to ensure the wax coats the whole of the inside of the mould evenly. This process is repeated until the required thickness of wax is achieved (this will be the final thickness of the bronze). The wax cast is now removed from the mould. The cast is hollow, as only a thinnish layer was built up in the mould. Wax rods (sprues) and a funnel- like cup are fitted onto the wax cast which will eventually take the poured bronze and allow for release of captured gasses. The sprue system and wax positive are then coated (inside and out) with a ceramic liquid.
The piece, now coated in a ceramic shell, is fired in a kiln. This bakes the shell and melts the wax, which runs out of the mould, leaving a cavity in its place. (Thus the term, “LOST WAX.”) The ceramic shell is removed from the kiln and molten bronze is poured into the mould. This is left to cool and the ceramic shell is cut and chipped away. The cooled bronze is a replica of the wax cast, including the sprues and funnel. These are removed by an artisan. Then by grinding, chasing, sanding and polishing, all areas are blended back to make the bronze look exactly like the artist’s original sculpture. The bronze is now treated with chemicals and heat to give it the chosen patination. The patina is sealed under a wax coating and becomes a permanent part of the sculpture.
Bronze Resins (also called Cold Cast Bronze)
Our bronze resins are made on site at our studio. I make the moulds (usually with help from my husband Bill!) and produce the bronze resins myself. This means I can control the quality of the final object. They look almost identical to bronzes, but are made of polyester resin, with bronze powder and colour added to the mix. They are sometimes called cold cast bronzes. Other materials can be added to the resin (the added material – which is in powder form – is called a filler) such as iron, aluminium or marble dust (or even larger marble pieces).
PROCESS: A silicon mould is taken from the original sculpture, which is enclosed in a case, usually of fibreglass, for strength. Mould making is an art in its own right, and takes many years of practice to perfect. For some of the more complicated sculptures, it can take days to make a mould.
A resin/bronze mix is poured into the mould and left to cure. The resin casts are then pulled from the mould. The cast is fettled (cleaned and any air-release holes or seams made good) wire-wooled, to expose the bronze, and waxed. The casts are numbered, as part of a limited edition.