Mig welder questions

My Miller 250 is capable of .020 - .045 wire MIG or duosheild fully capable of the thinest of material to 5/8 thick single pass. Stick with name brands. As a welder since 1982 I have run a lot on machines. For me Miller is the best for home use and for production jobs. The post prior to mine is correct. Proper fit and tacking is the key to no distortion in the sheet metal. TAKE YOUR TIME.