The I.D. welding operator controls the motorized positioning of the welding electrode for single and/or tandem wire welding. Positioning includes the use of floating wire feeder(s) connected to the welding head clamp. A spring-lined rigid copper tube houses and insulates the electrode wire, resulting in maximum heat effectiveness: at the weld nozzle and utilization of the maximum sized weld tips. In tandem welding the number two non-driven positioner becomes a slave to the motorized number one positioner. A dual welding head clamp moves both electrodes in unison.