Industrial designer Robert Hendrick was on a tech career track out of college until two things happened that changed his trajectory.

First, he bought a company that maintains and rebuilds railroad tracks. Then he started spending Saturdays building stuff with his father, Jim.

“I’d always been fascinated by trains and loved the history of how they were so instrumental in the industrialization of America,” says Hendrick, of Nashville. “Dad was a construction exec, and the carpentry shop was a weekend diversion. He was always salvaging some interesting artifact from a building that was being torn down. When I saw some of the scrap rails, I realized there might be some beautiful things we could make with them.”