This is a switching engine, intended to be used on the common wooden tracks that are produced for younger kids. I originally made these for my nephew.
I would like to expand upon this in the future, and add other cars. My little swithcing engine includes one big advantage over store bought trains. In the magnet used to couple the cars together; while it's common on store bought ones to have static magnets, my design uses a bucky-ball sized round magnet. Allowing it to rotate to match whatever the poloarity of the connecting car is.
Enjoy. Make sure to use plenty of glue when putting it together. But don't glue those wheels in place!