the only reason i'm posting is that i finally completed the transition from programmer to welder and i find my new peers generally smarter and harder working. fwiw
(I agree american investment in education is abyssmal, and I bet gp might agree too, but mistook your comment's meaning)
starting from nothing it took about 6 months practice and general skill building to where i could work on projects and not screw them up for everyone. one nice thing about this world is that if you aren't so good, you can still pull in minimum wage if you work hard. once you get the hang of things you can build up a client base and start charging more. and if you have any kind of flair for design you can start selling bespoke pieces instead of just being a pair of hands.
after about $60/hr it gets a lot tougher. you don't really qualify for the really high-end work (i.e stainless pharmaceutical). and no insurance.
I went back to tech for .. 4 years because of the pay difference and because of insurance for me and my wife, but I'm back in the shop now because..i think my software mindset is pretty radically different than the way things are done now.
trade work is a constant challenge, and you can see your skills grow over time. faster, cleaner, more reliable, more clever. if you have a little* financial flexility and love hard work, i strongly recommend it as a second career. if i'm lucky in a software shop i get to solve a problem a day, in the metal shop i solve tens or hundreds.
[oh, sorry, should make this clear - if you start in welding/machining you can certainly make quite a decent living, have benfits, etc - i'm just talking about coming in later in life being self taught and trying to carve out a little work here and there]