I agree that this isn't going to do much good. Either he gets it or he doesn't get it. Your life do what makes you happy and don't worry about other's opinion.
I am an Electrical Engineer working in the defense industry for 40 years. I have done Electronic design, Been a Test Manager and a Program Manager. I know a judge, a bank Comptroller many other engineers, Police Officers, Orthopedist, teachers and other professionals who love model trains.