Funny you should mention powered coach.  This is from a 1954 RMC article.

I have, of course, contemplated ways to make it operable but haven't come up with any solutions that would work while keeping it looking right.  One big problem is that it would need to have operating cog gears in the middle if it is to work like the real thing.  The string idea would work when viewed from a distance but I would want something more like the prototype.

I found this topic and thought you might be interested.  

The Mount Washington Cog Railway has always been a special place for me.  I too had been looking for a model of a cog railway with no luck.  So I designed one myself which I had printed out in 3d.  Custom decals were also created.

It's a static model, but I tried to keep it as close to prototypical as possible.



If Bachmann were to consider making a model, I would certainly share my design.  I wouldn't hold my breath though, the model is tiny.