What is MIG, TIG welding?
MIG welding, also called GMAW, extrudes a metal wire electrode from a gun held by the welder. Power is applied to the gun by a power supply that attempts to regulate voltage at a preset level set by the welding operator. The gun also carries a shielding gas to the nozzle of the gun. A trigger on the gun turns on the gas via a solenoid in the power supply and engages the contactor, also in the power supply. Current flows down the gun through the arc and back to the power supply via the ground clamp. This process has become very popular in the last 40 years because of its speed and ease of use. TIG welding, also called GTAW, uses a torch held by the welder to develop an arc. The power is supplied by a constant current power source. Unlike the MIG machine where the electrode is consumed in the puddle, the electrode is not consumed and filler metal is added by the operator. Current is then returned to the power source via the ground. Shielding gas is also supplied via the torch and it may