As with M.I.G welding, a hand held "gun" is used to control the weld, an electric current is passed between the electrode and the work via a metal tip surrounded by an inert gas shield. Unlike M.I.G welding, where the tip is homogenous to the metal being welded and acts as a filler rod, T.I.G welding uses a fixed tungsten bit, which does not come into contact with the work – it is drawn across the surface at a distance of around 1mm, melting the metal below as it does so. A filler rod can be fed into the weld with the user’s free hand as with oxy-acetylene welding.

The inert gas is dependant upon the material being welded but Argon is the most common. Its purpose is the same as for MIG welding; to shield the weld pool from the oxygen in the atmosphere. This would cause rapid oxidisation to such a degree that the jointing of the molten metal can’t take place.