An anonymous reader asked if American Flyer trains can run on Lionel track.
The answer, of course, is that it depends. American Flyer trains made before 1946 run on exactly the same track as Lionel. But the two-rail American Flyer trains made starting in 1946 run on their own track that is most definitely not Lionel-compatible. There’s no third rail and the two rails that are there are closer together.
The easiest way to tell is to flip the locomotive over. If you see some kind of metal contact shoe or plate in between the wheels that could contact a third rail, then the train can use Lionel track. If there isn’t, it’s a two-rail S gauge train that used its own incompatible track system.
Used 2-rail American Flyer track isn’t expensive. A decade ago it was very easy to find at flea markets and antique malls, and I can’t imagine it’s gotten much harder. Train stores that deal in vintage trains almost always will have plenty of Flyer track as well. But if you can’t find any near you, there’s always Ebay. Make sure the track looks reasonably clean, and pay attention to shipping, as shipping a large quantity of track can get expensive.