I've got the Lincoln 135, which is a mig, 110v. I use it for my artwork, and furniture, as well as any random repairs (like my parents' grill, which has a hard time staying on the patio on windy days).
It can weld aluminum, only it needs different wire and straight argon instead of 75/25 Ar/CO. I've welded leaf spring steel with it, truck rotors, and plate up to 1/4. I've also welded stainless and mild steel sheet with it. I've had it 4 years without issue.

I agree about not using flux core, but not because it doesn't look good. It is hard to get a good bead with it. Looks don't matter, especially for sheet metal since you are going to grind and pound the weld smooth anyway.

I don't know what the current number is for the Lincoln 110v gas mig. Maybe it's still the 135. Anyway, I highly recommend it if you want to spend the money. New it was $750 when I bought it, and ~$120 for the cylinder if you don't want to rent.


All that said, to be honest, I don't think you're going to get the value out of it if all you're going to do is weld a patch panel, an exhaust, and then look for things around the house you could weld. Take a welding class at the comm college or vocational school. Take the car there and take the exhaust. They can be your projects, or you can do them after class.

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1984 300TD