I run a fleet of trucks and the trailers have a lot of aluminum. The welders I buy are for the shop, but I use them for my personal use too. And of course there are times I weld when I don't have anyone in the shop. Most of the repairs are done with buck rivets or Huck bolts, but at times things have to be welded. Our trailers are built by Cornhusker 800 in Lincoln, NE. The engineer who worked with me to design the trailers we pull many years ago told me Cornhusker doesn't own a TIG machine. They do everything with push pull wire. He told me it would be a waste of money for me to buy a TIG and I think he was right. I don't have anything against the red ones. My first welder was a 225 AC DC that I bought 50 years. We used it just the other day when we did some repairs on an old rusty flatbed. It was probably the mid 80's when I bought my first wire machine. A Millermatic 200 and it is still my welder of choice on clean mild steel. Last November I bought a D500 pro at auction in Houston. I will never turn the heat up very high because I don't weld anything that thick, but it has a 3 phase generator which is nice to have. And it has constant voltage for an arc gouger and a wire attachment. As for welding things like patch panels I have a Hobart Handler 140 with CO2/ Argon at my house. It will weld thing a lot thicker than it is suppose to, but It has a very short duty cycle at higher heats. I wouldn't leave it at the shop because I think it would be easy to burn up. But I can weld stuff that almost looks like a TIG job with it. I had an aluminum flatbed built for my 3500 HD a couple of years ago and went to their place in PA to have it installed.
https://www.martinswelding.com/ The welds look like TIG but they too do it all with wire.
https://photos.app.goo.gl/rC4itJRcWTJRquhw8
