Reply to "Were post war engines made to run on O-31 track?"

@Lionelski posted:

While they will run on O31, if you are in the layout planning stages I suggest that you consider O42, O54 and O72 tubular curves - all were made by Lionel

Good advice that I myself learned here and have followed. Basement layout 2.0, while still using O27 tubular track, has only 42", 54" and 72" curves. No 27" curves other than in the yard where the switchers and freight cars will handle them fine.