I’ve taken apart several modern can motor Lionel 4-4-2 engines. I plan on making my own frames with bearings for the axles, then placing the can motor ahead of the drive wheels just above the rails between the fake steam cylinders. I’m thinking of a 4-4-4-2 setup with the middle two “4’s” driven. Do you think this will manage 42" curves?
Seems like an awfully long wheelbase for that curvature. Even if the wheels stay on the track the amount of play required over the front and rear trucks to hold the track may not be attainable or at best, will look quite unnatural. I’m assuming that you are planning on a scale loco. Semi-scale might be more achievable.
Poppyl
Semi scale using modern cast metal post mid 80s steam engine shells.
Traditionally, articulated steamers had the rear engine mounted somewhat rigidly to the boiler while the front engine and its frame was flexible. There were other loco builders, mainly European, who made both engines pivoting so as to allow their locos to work very tight curves, Koppel and Beyer-Garratt come to mind right off. Other interesting arrangements were tried but all suffered the same malady-that of steam-tight connections. Point I’m trying to make is, you can pivot both engines to allow better curve tracking. It’ll mean some head-scratching to develop your framework but the outcome could be truly unique. Please post a photo of your finished product! Neil
This will be a winter project.