I don't think a class is necessary, although I spent months struggling to weld with a crappy stick welder before stepping up and buying a used Lincoln Promig 130 for $300. It's really just point and shoot. I've only used flux core so far and I've welded structural and sheet metal, seems to work fine, although sheet metal is probably easier with gas and produces a better looking weld.

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1983 240D 3.0T 4-speed manual, now sold

1989 Subaru GL Wagon 5-speed Touring Edition