The invention relates to a spot welding rod for the resistance welding of workpieces, the rod comprising a drive, which displaces the pincer arms and is configured by a spur gear and a connecting rod that is connected to the gear, the spur gear being connected to one pincer arm and the connecting rod to the other pincer arm. Doping levels for different regions across an integrated circuit can be differently defined by making use of varying size and spacings to the perforations in the mask. An electronic circuit drives the optical system. The method initiates with a communication interface being provided between the first RF device and the second RF device. When a facial code is retrieved from the database, the element codes in the facial code are linked to the digital files using the table and the resulting composite image is displayed. The method includes the steps of mounting a positioning jig between the side walls to thereby position a plurality of unit support members, affixing the unit support members to one of the side walls, removing the positioning jig, and causing the unit support members to support the image carrier units and developing unit.