In 2007, in his Wisconsin studio, sculptor R.T. Wallen began his work on Tahku. his first step was a two-foot hight model. He then scaled up to an intermediate size of 8 feet hight, and finally to the full-sized whale. At each step in the process, he made adjustments for design, accuracy, and engineering.

All three sculptures- the 2-foot and 8-foot study models, and the full-size whale - were cast using lost -wax casting. This process starts with an orignial sculpture in clay over a supporting armature of rigid foam or wood. Latex and fiberglass molds are made of the sculpture, and was cast are made from those molds. Ceramic molds are made over the wax casts an then heated to allow the wax to melt out. Finally, molten bronze is poured in the ceramic molds. When cool, the ceramic molds are broken apart to reveal the bronze casts.