Impressive heavy equipment repair with cutting, welding, machining, liquid nitrogen dipping.

He is basically blasting the metal with arc welder and compressed air
called gouging.

Faster than grinding and also easier to profile.
Wow, the man knows his machine shop practices. I don't think I have seen that many different machining, grinding, and welding processes all together ever! And liquid nitrogen! Wow.

Thank you Atikovi.
My title wasn't as impressive.

But I really like his vids as well. Seems like a smart dude and he built all that just him and his wife. Good on him!!

He goes into why he uses the gouging process on his latest video:

What is he doing at 3:15 and why is it better than using a grinder? And what would he have billed for all that work? Wouldn't a new A frame thing be cheaper?
Granted, it was a hydraulic cylinder, but he talked about in one of his videos that he could completely rebuild 2 of the cylinders that were pretty well completely trashed and still have money left over VS buying a new one. He also mentioned that those parts aren't just something the companies keep on the shelf, they have to basically be built from scratch anyways, so you're still waiting weeks, and paying over double.

Big equipment like he's working on is a whole other world. We're used to ordering parts from RockAuto and the like, that just doesn't exist in that world.
While I have not dealt with them yet ( I am working on a design of a hydraulic project that may require parts from them ), from what I have seen on some sites and YouTube videos, Scott industries stocks a lot of hydraulic piston shafts, and cylinders, and can usually shorten existing stock for you in short time while maintaining the quality of the part.
Never heard of that, not that I know much about welding.
We had one where I worked . The one we had uses a carbon rod instead of a regular welding rod so what happens is compressed air blows out the molten metal . I played with it it often but like welding It takes lots of skill which I didn't have.