The Manufacturing Process
Fabrication of floor and body panels 1 The floor and body panels are made of sheet steel, aluminum, or fiber glass. If sheet metal is used the metal is cut to size in a sheet metal shear, a machine that cuts it with giant scissors. It is then fed into a roll forming machine, which shapes the metal by passing it over contoured forming rolls. If fiber glass is the chosen material, the floor and body panels are formed as one piece by inserting layers of resin-coated fiber glass in a mold and allowing them to harden. Chassis construction and painting 2 Tubular steel, which resembles square bicycle handlebars, is cut to size and the edges beveled (cut at an angle of less than 90 degrees) to prepare them for welding. The cut, beveled pieces are then placed in a welding fixture, and the chassis, or frame, is arc-welded. In this process, an electric current is fed out of the welding torch through a metal wire that is shielded by a concurrently emitted inert gas (usually argon or helium). As the wire melts, it joins the tubes to form the chassis. Next, the floor is welded in place, and the attaching hardware for the suspension, motor, and body are arc-welded to the frame. At this point, the chassis may need to be straightened to adjust for stresses introduced into the steel tubing during welding. Once it is straight, the chassis and body panels are cleaned and painted with a rust-preventive finish coating.