The Lincoln stick welder Idealarc R3R-500 Description: Substantial amperage ranges include the R3R-500 at 72-625 amps; Easy to operate - Calibrated current control knob makes procedure setting simple and easy; Polarity switch, voltmeter and ammeter are standard on the K1286-16 R3R-500; Arc gouge with the R3R-500 using up to 3/8 in. (9.5 mm) diameter carbon electrode; Smooth arc - Makes it easy to weld with mild steel, low hydrogen, stainless steel and hardfacing electrodes