Welders join metal by heating the joint above the melting point of the metal. The heating is done by passing current across an air gap between the joint and the welder tip. An arc is formed, and as the sparks fly, some of the metal is vaporized. The welder replaces this with a filler metal. In the case of a MIG welder, the filler metal is a spool of wire fed through the tip of the welder. An inert gas is sprayed around the metal joint to protect the metal from oxidation while the metal is molten.
What is the first project to make with the welder? A welding cart of course. The goals of the cart are to make the welder mobile (the transformer in the welder is heavy), and to store all of the accessories in one location.
My 2 year old son is car crazy. He loves car shows (Disney's Cars, Top Gear), toy cars, and playing in the Porsche.