The Tokyo Tower model was built by a metal works company. The tower model was built using blue prints by the Toho effects staff who photographed and researched the real tower. However, the blue prints only showed one side of the tower, which forced the metal works company to figure out the angles to build the other sides. The effects staff had initially requested the original blueprints of Tokyo Tower but were unable to obtain them. Toho closely guarded the custom tower model blueprints to keep competing studios from benefitting from Toho's work. Mothra's silk was created from a form of liquid styrofoam called "expanded Polystyrene". A small model and large model was built for the atomic ray cannon.