I am thinking about buying a MIG welder and teaching myself to weld by doing the right side of my trunk floor which is swiss cheese. I think this would be a good 1st project. I am looking at under $400 welders. Any tips? I have watched a few youtube videos and it seems meticulous but pretty straight forward. Cut out the old floor, fit, fit and refit the new floor. Clamp. Weld.
It was never that easy for me. Welding requires good hand eye coordination and with TIG you add a throttle to control the heat of the gun. I think you should consider a more expensive TIG, MIG, Stick welder that has all of the functions for welding anything up to 3/16 inch thick. You rarely weld anything thicker than that, and such a machine allows you to dial it back so you don't blow a hole through the first piece of tin you try to weld. They also usually have automatic speed and feed dialed in when you tell the machine the thickness of the metal you want to weld. You will need a few different spools of wire to weld different materials with MIG and different tips and gas mix to weld aluminum or steel with a TIG. Stick welding is generally for cast iron repair or building steam ships now a days.
If you can weld with a gas torch (the way I learned) so you have a pretty good handle on TIG welding already, which is why I like it better than MIG welding. It also gives a cleaner weld, with less grinding and no spatter.
Check out the Lincoln and the Hobart-Miller web sites for more info. Miller offers pretty good end user support to get you up and running.
I did something similar on my impala, teaching myself to weld.
I might recommend ensuring you get a welder that allows for the use of an Argon/CO2 gas tank and solid wire, instead of using flux-core wire. I think it's a little cleaner and with less spatter.
Other than that, make sure both pieces of metal are clean clean clean to raw metal. You might want a magnet or 2 for places you can't get a clamp in place.
Watch for good heat penetration by the discoloration of surrounding metal when done welding. It should have a blue edge a quarter inch or so outside of your weld-line.
You probably are aware of the heat-warping, so be sure to weld at different ends of any panel, keep a wet cloth around, and an air nozzle works nice if you have one to cool things off.