TIG welding is used with or without filler metal. It makes it possible to assemble parts of small thickness, and that in all the positions.
Some MMA welders may also work to perform a TIG weld. This requires equipping them with a cylinder of inert gas (argon) and a special TIG torch valve (connected to the pole -). The mass clamp is always the same.
In the torch, the tungsten electrode must be sharpened for better accuracy. Depending on the thickness of the part to be welded, all the settings have to be modified: choice of the electrode, size of the nozzle which diffuses the gas, amperage, and size of the filler metal if you use it.
Mixed electrode (MMA) and TIG mixed models exist. A single button usually switches from one mode to another.
Arc welding with filler metal
Hold the electrode 2mm from the plate and form the melt.
Bring the rod to the gas protection zone without making contact with the arc.
Move the melt while holding the wand in place
At the end of the welding, do not cut the gas until after cooling the electrode (a few seconds).
The solder must be clean, of silver color, without slag, and have a very small thickness.
Arc welding without filler metal
After priming the arc, tilt the torch 75° to form the melt: it should be about twice the diameter of the electrode.
The metal becomes shiny, red and fluid, the two pieces agglomerate.
Gently advance the torch...
You can do the welding at one time.
The weld should be smooth, slightly recessed with respect to the two plates.