Way back. I had a Miller stick welder. The Sears surplus store had a high frequency TIG conversion unit. So being the tool freak that I am. I bought it and hooked it up to the Miller..
First job was an aluminum canoe that was ripped almost in two about 1/3 back from the front.. The setup worked. Not like the big square wave at work, but it worked. Next was an airplane fuel tank. Then fabricate the auxillary fuel tank for the Sloan museum entry, a 32 Chevrolet roadster, for the Great Race.
Then I decided to go big time. So I sold the setup to a friend and bought a real TIG welder.. Loved it. But at that time such a welder was about half the size of a Volkswagen beatle..
Glad the new stuff is so much smaller and better.!