I learned machining by…..Doing. I never intended to be a machinist, it just kind of happened. In the early 70s I was working on an experimental project and took some drawings over to a local machine shop to have the parts machined. I was a bit shocked at the price and figured that I could do that. I took metal shop in high school and had a little machining experience there with a lathe and a shaper. The parts also needed some modification so I went to Sears and bought a Craftsman Commercial 12x36 lathe. Shortly there after I found a used Atlas mill and shaper. I never did finish the original project. Never had any problem learning how to make chips, I just kept learning from my mistakes. I guess I just had a feel for it. Never did have any formal training, an apprenticeship, or even a mentor.
At the time I was working as a millwright and the company I was working for needed some parts machined, so I said ‘’I can do that’’. Well they needed quite a bit of work done, so I quit and started machining for them full time in my little shop. I pretty much wore that poor lathe out in a couple of years building Inconel spindles for them. And yes, you can hold +/- 0.0002 on an Atlas lathe, even a worn out one. Time for some bigger equipment, so I traded in the Atlas equipment and bought a new 14x40 lathe and a Bridgeport clone. I didn’t have room for the equipment at home, so I rented a small shop space and hung out a sign.
After I got tired of that I sold out that business and took a couple of years off building fast cars, flying, and SCUBA diving. Then decided it was time to go back to work. Went to work as a maintenance tech for a while until they went on strike, then saw an ad for Tool&Die maker wanted. Yeah, I can do that, never done it before, but that doesn't stop me. I've got a pretty good line of BS to get me in the door. A couple of years later I'm running the shop building high speed stamping dies, I guess they were happy with my work. I stayed there for 7 years, a new record. Then I had to get out on my own again. Bought another lathe and mill. So for the last 45 years I have either owned or had access machine tools at work. My primary focus is machine design and building, I never really considered myself to be a machinist. I just use machine tools as a part of the process.