Metal Inert Gas (MIG) Welding

I spoke with one of my friends today about helping out with the motorsports team by learning how to weld. I think there are basic skills that every engineer should either know how to do or have a knowledge of how it works, welding is one of those skills. MIG welding uses an electric arc to melt the target pieces of metal and the filler metal. An inert gas (usually Argon) is blown around the weld site to prevent interaction of the hot weld with the atmosphere. The gases in the atmosphere (78% Nitrogen, 21% Oxygen & 1% trace gases) can cause defects in the weld.