Julian Cross FIPG
Artist Sculptor & Goldsmith
Relief carving is a sculptural technique which has been in use for centuries in its different forms from high relief plaques and statues of ancient Egypt, Greece and Rome through to intaglio (in reverse) carving of great mediaeval Royal Seals such as for the Magna Carta, and continuing through to the bas (low) relief work found on coinage today, a practise in use in the minting process around the world. Julian produces work in both bas relief and intaglio to meet the needs of a wide range of clients as well as sometimes just producing beautiful works of art with this technique. Sometimes the maximum height of the relief across the whole piece can be as low as 1.5 mm (60 thou) and within that depth Julian still manages to capture all the subtlety of shade and form.
The resulting sculptural works made from the relief technique can be utilised for a variety of production methods to produce finished pieces, principally they would be casting, minting or electro-forming.
Casting involves the cire perdu or lost wax process, an ancient method which in essence has changed little over thousands of years. Although in modern times it is called investment casting, a wax model is still the starting point of the whole process as it has always been. An original model or sculpture, if not already in wax, can be reproduced in wax by creating a silicone rubber mould and producing a cast wax from that master mould. The resultant wax, which will have every fine detail of the original, is then "invested" or coated with a ceramic shell or plaster and after prolonged heating in a kiln the inner wax is then burnt out, hence the term lost wax method. The negative void in the ceramic plaster that is left after the wax is burnt out is the space that molten metal is then poured into at around 1000° celsius (2000°F). When the whole casting has eventually cooled down many hours later, the plaster is broken away from the casting to reveal an exact metal copy in place of of the original wax. The metal surface is then worked to the desired degree of finish and polish to produce the finished item. This is a simplified version of the process.
Minting requires the production of a die or punch to be made from the original artwork so that a blank piece of metal can be struck or minted with the design. Commonly a design would be made in plaster on a blank disc about 20 cm diameter to enable the artist to work very precisely at that scale. Sometimes the depth of relief even at that scale must be kept to below 1.5 mm across the whole design. The finished artwork must then be reduced in scale to the size required and transferred with all the detail to the hard steel of the punch. There are several modern techniques now commonly used to transfer the original artwork or plaster relief to a punch as well as traditional methods invented in the last century. Laser scanning of an original is sometimes used and then further use of lasers to cut hard steel dies. More traditional methods use complex reducing machines like pantographs to cut the steel die at the reduced scale. The resulting negative impression die is then mounted in specialist presses where a blank disc of the required metal is "struck" or pressed at extremely high pressures and this pushes the metal into every exact detail of the original artwork or design. This is a very basic description of the method used in minting and coin production and which is also used for some medals and plaques.
Electroforming is a relatively modern process that has developed from the metal plating process. In essence electroforming is a method of depositing metal onto a metallised base model similar to the basic plating process. It requires that the deposit is of sufficient thickness so that when the base model is removed the resulting piece has sufficient strength to be a self supporting structure. Recent advancements in technique now mean that light and strong sculptural objects can be made in precious metals that closely follow the modelled master pattern. These models can be in wax, as can be seen in many of the models in the Sculptures & Master Patterns section, which have then gone on to be electroformed.
Bas Relief & Intaglio
Scroll through the images and click on any picture for more details