I know my great-grandfather worked for the railroad, but I don't have much information about what capacity he served in.
My great-uncle was an engineer.
And my grandfather also worked for the railroad, as a machinist. My understanding is that he worked on the boilers of the steam locomotives at the machine shops for the New York Central(later the Michigan Central) in Jackson, Michigan. Below are some pictures of said shops. The buildings still exist today, though they're used as warehouses for a large freight company. The railway still runs as well, being part of the main Amtrak line between Detroit and Chicago.
And also, just because I can, a photo(again not mine) of retired Grand Trunk Western 4-6-2 locomotive 5030 at R.A. Greene park, also in Jackson.