Research into ancient casting techniques

Research taken from Metropolitan Museum of Modern Art

“The ancient Greeks and Romans had a long history of making statuary in bronze. Literally thousands of images of gods and heroes, victorious athletes, statesmen, and philosophers filled temples and sanctuaries, and stood in the public areas of major cities. Over the course of more than a thousand years, Greek and Roman artists created hundreds of statue types whose influence on large-scale statuary from western Europe (and beyond) continues to the present day.
The earliest large-scale Greek bronze statues had very simple forms dictated by their technique of manufacture, known as sphyrelaton (literally, "hammer-driven”), in which parts of the statue are made separately of hammered sheets of metal and attached one to another with rivets. Frequently, these metal sheets were embellished by hammering the bronze over wooden forms in order to produce reliefs, or by incising designs using a technique called tracing.

By the late Archaic period (ca. 500–480 B.C.), sphyrelaton went out of use as a primary method when lost-wax casting became the major technique for producing bronze statuary. The lost-wax casting of bronze is achieved in three different ways: solid lost-wax casting, hollow lost-wax casting by the direct process, and hollow lost-wax casting by the indirect process. The first method, which is also the earliest and simplest process, calls for a model fashioned in solid wax. This model is surrounded with clay and then heated in order to remove the wax and harden the clay. Next, the mold is inverted and molten metal poured into it. When the metal cools, the bronze-smith breaks open the clay model to reveal a solid bronze reproduction.

Since the physical properties of bronze do not allow large solid casting, the use of solid wax models limited the founder to casting very small figures. To deal with this problem, the ancient Greeks adopted the process of hollow lost-wax casting to make large, freestanding bronze statues. Typically, large-scale sculpture was cast in several pieces, such as the head, torso, arms, and legs. In the direct process of hollow wax casting, the sculptor first builds up a clay core of the approximate size and shape of the intended statue. With large statues, an armature normally made of iron rods is used to help stabilize this core. The clay core is then coated with wax, and vents are added to facilitate the flow of molten metal and allow gases to escape, which ensures a uniform casting. Next the model is completely covered in a coarse outer layer of clay and then heated to remove all the wax, thereby creating a hollow matrix. The mold is reheated for a second, longer, period of time in order to harden the clay and burn out any wax residue. Once this is accomplished, the bronze-smith pours the molten metal into the mold until the entire matrix has been filled. When the bronze has cooled sufficiently, the mold is broken open and the bronze is ready for the finishing process.“

(see this article in full at MetMuseum )

Sketches for new woven wax shapes, which to choose first?

The experiments with learning crochet have worked well, and I have now transferred the technique to my work with wax.

Using a crochet chain stitch is the first step, this chain is hand crocheted and then the chain wound around a polystyrene ball to form the first halve of a sphere.

Step two, the chain is stitched together with a swirl weave, in the same manor as my willow weaving.

The 100th Chelsea Flower Show open to the Queen and the Royal family, and Rachel receives her third RHS award in as many years.

Metal weaving cont. the experiments with weaving metal has come to an end, the process used is pretty much the same as weaving with willow, but the strenuous nature of wire on the fingers is very different (See earlier post about the physicality of art). The frame work begins with a single circle of woven wire, then further circles are added, weaving them in to the frame work as you go. Once a complete sphere of circles is finished then the next layer is added, just like willow weaving, I call it my messy layer. The job of the messy layer is to cover the entire surface with a mass of lengths zig zagging across the surface, this has two important factors. One - to cover over as many open spaces a possible, and Two - to provide anchor points for the decorative weave later.

The Mickleover Sculpture arrives on the lorry and is lifted by crane into place over the foundations 

The physical nature of Art and the artist

For a long time now my professional practice has revolved around weaving materials such  as willow to create spherical art forms for the landscape, the natural form of the sphere and of willow work hand in hand to create a piece of art that encompasses nature on all levels. But, when you change a singular element of that art work does it continue to have the same effect on the viewer, does the art continue to function as art and most importantly how does this effect the artist? 

The latter of the statements is commonly the most overlooked and it for that reason I have chosen to write about it. I will begin with process and materials. 

Working with willow on large scale sculpture, you tend to work standing up with the art on a bench, or like me sometimes a disused cable drum. I find myself constantly moving either to the sound of the radio or to the rhythm of conversation whilst working, my feet never stop and my hands, (never with gloves on), are feeling the willow branch as I weave for its malleability seeking out any parts that need extra attention to help it curve in the path of the weave. This dance and weave has been my art form for around 7 years, but recently I have wanted to try out something new, to weave in a new material but retaining the spherical nature of the art form.

Weaving requires a material that can be manipulated into shapes and if that material has a memory then even better as the weave will stay in place after you let go and not, as happens many times, bounce away from the weave and hit you. Perhaps a subtle way to let you know you haven’t woven it properly.

I began with wire lengths in either brass, copper or bronze and began weaving them in the same manor as willow but with the cost of the metal, the overall scale was reduced.

To weave with the wire lengths standing up was difficult so the first change was introducing a chair, which after sitting in it for 6 hours left me feeling very uncomfortable and stiff, I could not move around freely as I usually do and it made me feel very restricted.

The second change was to my fingers and muscles, they have become so accustomed to willow that they also felt constrained and could not move the metal in the same manner. 

By nature I am not someone who gives up easily on something and after the first day of weaving metal I felt awful, I was not going to let it get the better of me, so I have persevered with it for 8 weeks so far. Two sculptures later, I still don’t like the changes in my body, I can no longer move my feet around whilst working or talk simultaneously so I have stopped listening to music and have swapped to talk radio stations that broadcast plays. The sound of the actors have soothed my need to get out the chair and move, as well as giving me a new type of rhythm to work to. My hands ache and have begun to get rough patches on the ends of my finger tips from pushing the fine metal lengths into place. But the bounce back from an unsuccessful weave has now been replaced by scratches and pierced skin, so I look like I have been fighting with a cat!

This is not the end to my experiment, only the start, and I will continue to persevere through the changes, but I felt the need to let you know that when you come across a sculpture please consider the blood, sweat and tears that have helped shape this piece of art. The difficulties artists encounter on a daily basis to create something so personal and present it to the world. I wouldn’t have it any other way.