Metal Inert Gas. A form of gas shielded arc welding that consists of a gun which feeds metal wire into an arc shielded by an inert gas or gas mixture. Produces high quality welds compared to SMAW (stick welding) but not as good as TIG welds. Also, like TIG, MIG cannot be used in an environment with heavy winds as this dissipates the shielding gas.The exception to this rule is if flux core wire is used, then little or no shielding gas is needed.
Many steel and aluminum bicycle frames are MIG welded.