Using a variety of modeling techniques and tools the design of these shapes is created using CAD software. The next stage is to get them from a virtual model to a physical object - this is accomplished by direct-metal printing. The design is laid down, one layer at a time, in stainless-steel powder, held in place by a laser-activated binder. You can see the remnants of the layering on the finished pieces and each layer is .004" to .007" thick. The piece then goes into an oven, where heat drives off the binder and fuses the steel powder that was used during the printing process. This produces a porous steel sculpture that's about 60% dense.
The next phase is to get rid of the porosity by replacing the airspace that remains in the piece with liquid bronze. To do this the sculpture is heated again, and special stems that protrude from the piece are dipped in a crucible of molten bronze. Capillary action causes the bronze to wick throughout the piece. Impossible as it seems, the end result is a composite metal that's fully dense with properties intermediate between steel and bronze.
The bronze is oxidized to a nice brown color, using heated sulfur and ammonia compounds. Most of the oxidation is then removed by tumbling the sculpture with abrasives, which smooths the corners and the roughest parts of the texture. Lastly a burnishing tumble with steel shot puts a shine on the piece, followed by a light oil dip to seal the surface.
