Jared R. Lynn, Department of Art
My proposal was to create five larger than life-size heads out of aluminum. I did this to explore the importance of scale in the perception of sculptural objects. Scale, in this instance, is the size of an object as it relates to the viewer. If an object, is larger, it has more presence. Consequently, it will hold the viewers attention longer. My sculpted heads are much larger than normal human heads, and therefore they portray larger than normal human emotions. Outlined below is a brief chronicle of the process required to complete this endeavor.
This was the first project of this magnitude that I had ever attempted and therefore I had no idea of the obstacles which lay before me.
My first procedure was to fashion the original head out of clay. This would be a large head with an elongated, slender neck and small shoulders. Due to the awkwardness of the sculpture and the inability of wet clay to support itself at this size, it was necessary to build a steel armature. A steel armature is like an inner frame or skeleton that provides structural support to the heavy clay. After this armature was welded to the appropriate size and shape. I applied a primary layer of plaster to build up the mass of the head. once the plaster was hardened, I applied the clay on top of it. I shaped and molded the clay until it was exactly the way I wanted it. Once I completed the clay original, I began work to make a mold of it.
I had to choose between rubber and plaster as mold materials. Rubber is more flexible, lasts longer, and duplicates the texture more accurately than plaster. Unfortunately. rubber is very expensive to use on a piece as large as mine. As a result, I chose to use plaster which is heavy and rigid, but less expensive.
Everything seemed to go smoothly to this point. However, I was a little over anxious and began to make the plaster mold without considering all necessary procedures for this step. As a result, I made many mistakes and caused myself a lot of frustrating extra work.
The plaster must be applied in layers. Once one layer is hard, it must be soaked with water before the following layer is applied. This is one of the steps which I overlooked. It caused my first layer to be very brittle and I lost a lot of the details in the texture of the head. These details had to be touched up later when the heads were cast in wax.
Another mistake I made was to build the mold in two large and heavy pieces rather than in smaller, more manageable pieces. This caused me a lot of physical strain. Because of the poor quality of the first plaster mold, I was only able to make one wax copy of the head before the plaster deteriorated. Luckily, this wax head was good enough to use to make a new plaster mold. I had to use the wax head this time as the clay head was destroyed in removing the first mold from it.
This second plaster mold was properly made and from it I was able to cast five perfect wax replicas of the original.
A wax casting is made by pouring melted wax into a moistened plaster mold. Once the wax has cooled inside the mold, it is removed and is ready for any necessary touch-up work. Making adjustments is easiest to do while the sculptures are still in their wax form. Once I had completed all the touch-up work for each of the five heads, I cut each of them into four small pieces with an Exacto blade. These smaller pieces would be easier to cast in aluminum, and could be welded back together afterwards. I now had twenty pieces of wax to prepare for casting.
At this point, I realized that I was far from done. Each wax piece had to be attached to a series of wax bars which aid in the casting process. This required from a half hour to an hour to complete just one piece.
After a few days of working to attach these wax bars, I was ready to apply the ceramic shell. Each wax piece was dipped in a ceramic solution called the slurry. As the slurry dried, it hardened to form a thin shell. This piece was then dipped again and another thin layer formed over the first. This dipping process was repeated eight to ten times before the shell was thick enough to resist breaking. Each layer applied had to dry for at least six to eight hours before another could be applied over it. This became very time consuming and exhausting as I had to dip twenty different wax pieces. As the layers increased on each piece, so did the weight. After a few days of dipping, I was hefting pieces of thirty pounds or more, and trying to be as gentle and careful as possible.
Once the shell was thick enough, all twenty pieces were hauled to a local foundry where they used a machine called an “autoclave” to extract the wax from the shells. The sculptural parts were loaded into the machine a few at a time and exposed to pressurized steam instantly melting the wax inside the shells. The wax pours out a vent hole in the bottom of the shell and is recovered for later use.
The hollow shells were then hauled back to the studio to patch the various cracks and fissures which formed during the wax extraction. After patching, the shells were baked in a furnace at between 1500 and 2000 degrees Fahrenheit for four hours. This is called vitrification and hardens the shell to prepare it to resist the shock of molten metal that will be poured into it. While the shells are being heated, large amounts of aluminum are being melted for the pour. Once the shells reach temperature, they are removed from the furnace while still red hot. The vent hole from which the wax in the shell poured out is placed facing upwards and the molten aluminum is poured in. The liquid metal fills the void inside the shell where the wax sculpture was before.
Once the metal has cooled sufficiently, the shell can be broken away with a hammer and chisel to expose the metal pieces of the sculptured head. Before all these pieces can be welded back together, they must be thoroughly sand blasted to clean away any loose bits of shell. The edges of each metal piece must also be ground so that the weld will hold. The four pieces of each head fit together like parts of a puzzle, and are welded into place. Welding a single head took me an entire day because I was learning as I went along. I would often have to grind down a bad weld and start over again. As soon as the welds were completed I ground the seams down flush to blend them into the texture of the head. The head was finished by adding a light wash of stain to give it some color and to enhance the texture.
The completed sculpture now only lacks a creative form of display. This is a challenge I am still responding to. All in all, this has been a long and arduous process but the experience I have gained is invaluable to my career as a professional artist. I am grateful to the Office of Research and Creative Work for their financial assistance in bringing this project to fruition. Exploring my ideas through working on a large scale would not have been possible without their generous aid.