1. Get a good ground clamp - Spend 20 bucks and get a copper ground clamp with a strong spring. Your mig welder is not smart enough to know when your ground is not good and so it just keeps on feeding wire. This is why some wire welders sound like a drive by shooting when they first light up.
2. Watch your stickout - Stickout is controlled by how far away you hold your mig welding gun. But it is also increased if your contact tip is recessed way back in the mig nozzle. Adjust the mig gun nozzle so that the tip is flush with the nozzle or even protruding a tiny bit.
3. Shielding gas - 75 argon 25 cO2 is the standard. Plain C02 works too. If you have a 115 volt wire feed welder that only welds with flux core, sell it and buy one with a gas conversion kit.
4. Welding wire - for bare wire welding, use E70S6 , for flux core use Lincoln NR211. There are other good ones buy lets keep it simple.
5. 115 volt vs 230 volt - 115 volt wire welding machines are great for sheet metal and up to about 3/16 inch in a pinch...Next time you are behind a boat trailer, think about whether it was welded with a 115 volt wire feeder welder or a 230 volt mig welder, or a 230v stick welder. After you get that chill down your spine, slow down and put some space between you and the boat, Then make you your mind never to weld anything like a boat trailer with a 115 volt mig.
6. Bare wire vs flux core - flux core will weld hotter and thicker and outside in the wind. Bare wire is better on really thin metal and looks better.
7. Mig welding polarity - Reverse polarity Electrode positive is for bare wire welding. Some flux core wires require changing the polarity in order to weld ok. Since mig welding machines don't have a polarity change switch, this requires you to swap the leads. It is easy and takes only a couple of minutes, but some people never think of it. Lots of 115 volt mig welders are sold on Craigslist because someone forgot to change polarity for flux core welding and because of that alone, think their mig machine is junk.
