BEYOND BY LEXUS has a detailed story on BBS Wheels, the company responsible for the wheels found on the high-performance Lexus vehicle lineup:
At the Takaoka plant, craftspeople are running through the motions of making a one-piece Lexus wheel. A round piece of aluminum billet is heated to about 480 degrees Celsius (896 degrees Fahrenheit) and placed into a large hydraulic press, as tall, it seems, as a three-story office building. The machine drops 9,000 metric tons of pressure onto the billet, pressing the aluminum into a mold.
For wheels on the Lexus IS F, RC F, and LS F Sport, there are additional steps in the manufacturing process. The general manager of the OEM Sales Department, Akihisa Miyoshi, explains how “after these wheels are painted, they undergo either a partial buffing or diamond cutting process.” The partial buffing process is executed by an outside specialist, he says, who buffs part of the spoke “to create a samurai sword-like shape and finish to the metal.”