Construction of a vehicle body structure by welding thin sheet metal panels to thick metal extrusions

A vehicle body structure comprising:

• a substantially thick load bearing metal plate;
• and a preformed substantially thin sheet metal panel wherein the sheet metal panel is preformed by bending along the edge forming a hem line substantial in length to help distributing the heat away from the welding spot on the sheet metal panel during the welding operation and is substantially perpendicular with the surface of the sheet metal panel. The preformed sheet metal is disposed substantially perpendicular and edgewise at the hem line along the longitudinal edge of the load bearing metal plate forming a joint line for welding. The longitudinal edge of the load bearing metal plate adjacent to the sheet metal hem line is substantially beveled for welding. A plurality of tack welds is placed on the longitudinal edge of the load bearing metal plate and the bent knee of the sheet metal panel hem line to hold the sheet metal panel and the load bearing metal plate together. A plurality of tack welds is placed along the ending edge of the sheet metal panel hem line to hold the sheet metal panel hem line to the load bearing metal plate. A uniform weld line is applied at the joint line between the longitudinal edge of the load bearing metal plate and the adjacent bending knee of the sheet metal panel hem line. The excess materials above the surface of the sheet metal panel and the edge of the load bearing metal plate are removed to form a vehicle body structure having a smooth exterior surface with the load bearing metal plate as an edge trim and having an interior surface concealing the hem line adjacent to the load bearing metal plate from the outside view of the vehicle body structure.