Since completing my apprenticeship, in 1972, like many, I headed out into the world to get experience, and to find my particular niche in the machining world. I worked in many different places, and countries, but quickly found I was not suited to high volume production work. I ended up in several small shops doing things like stamping dies, building and repairing, job shops doing whatever came through the door.
I discovered along the way that I was good and making things from limited input, what I refer to as an envelope sketch and a lot of waving the arms around. I would talk with the person and try a figure out what was wanted, make my own drawings as needed, and usually deliver exactly what was wanted.
It was that problem solving skill that led me to my own machine shop, and kept it open for over 25 yrs. 
Some of the type of work I have done includes: Robotics – manipulator arms, Pan Tilt prototyping. Thermochromic plastics – proof of concept molds, special tooling for manufacturing. Unique semi-custom orbital welding machines, some use in nuclear heat exchanger repair. Specialized orthopedic furniture. 
And I still enjoy it for the most part.