On this page will be pictures of sculptures I made in Fall 2010. I have carved several versions of torus knots out of wood and stone, so I decided to also make some of bronze. I prepared two wax models of the (3,5) torus knot, one about 6" in diameter, and another 12" in diameter. The smaller one was solid, and was cast as solid bronze weighing about 6 pounds. The larger one would be much too heavy and expensive if it were solid, so I made it hollow, and even so came out to be almost 24 pounds. To make it required the preparation of a core of mold material (plaster and sand) in the shape of a torus, carved into the (3,5) torus knot. That core was dipped repeatedly into a vat of hot wax to make a 1/4" layer of wax on top of the core. The result was gated and then pierced with core pins. When the result was immersed in a large cylinder of mold material, the core pins were held by the outer mold, and they held the core in place after the wax was burned away in the kiln. Otherwise, the core would have fallen down when the wax was gone, and the desired 1/4" thick surface forming the sculpture would not have been formed when the bronze was poured through the gating into the mold to make the sculpture.
It was necessary to have a window open in the surface of the wax so that the core material could be removed after casting, leaving a hollow shell of bronze. That small window was also cast so that it would be welded back into the surface later. I should have made two windows on opposite sides of the torus, because I found that it was difficult to remove the core material from the side opposite the window. After a lot of effort trying to do so, I finally cut another window on the opposite side, cleaned out all of the core material, and welded back both pieces to close the windows. Holes where the core pins were also had to be repaired by welding, and show in some of the pictures below.
Pictures of the results so far can be seen in the pictures below. First are two pictures of the smaller 6" solid torus knot:
Next are two pictures of the larger 12" hollow torus knot with some welding repairs still needed:
Here is a picture of the larger 12" hollow torus knot mounted on a bluestone base (16"x15"x2"), over a mirrored dome. The idea to have the piece displayed over part of a sphere, to contrast the different curvatures, was suggested by my daughter, Judy. The piece is supported by a 1/4" bronze rod, which sits in a 1"x3.5" bronze rod under the mirror, welded to a bronze plate which is bolted to the stone. This allows the piece to rotate for viewing from any angle, and to be removed.
To see more types of sculpture I have tried, follow the following links:
Links back to:
Webpage of Alex Feingold,
Department of Mathematical Sciences,