When I lived in PA, we used to go to Cabin Fever Expo every year. It's all about model engineering/machining. Most are retired machinists that make scale model working engines. It is a hoot to go spend the day there if you're anywhere close. One year, a guy had a working model Merlin V-12 a little less than a foot long. Just never know what you're going to see.
https://www.cabinfeverexpo.com/-RP