Keith, my father made John Deere tractors for about 30 years. Mostly a heat treat furnace operator. But for a time, he also ran a machine called a Magna-Flux, checking for flaws in parts. He liked the job but could not continue, because he was allergic--if I recall correctly--to a liquid involved in the process. He also took some flak for rejecting parts the foreman thought should have passed.

Thanks for the comments.