This is the Time Machine made out of a 19th century locomotive for the movie Back To the Future III. If you have not seen this train you can take a close look at it in this video clip
. Despite the fact that the overhauled time machine is only shown during the very last 3 minutes of the movie, through the years it has developed into an iconic symbol of this incredible trilogy and a "must" for BTTF collectors.
The set is made in two independent parts. The locomotive and what seems to be some sort of a remodeled coal wagon. There's very liitle explanation in the movie as to how the train functions except that it is "fueled" by plain water and that to transport to one time to another, the wheels fold inward and it deploys some bat shaped wings from underneath while it flies to its destiny.
I choose to make this train as a fully functioning LEGO train. The base is an adapted copy of the Night Emerald including the internal mechanism which makes the gears at each side to roll as the train goes over the tracks, powered by a 9V/6 wheels train engine. Both pieces are attached to each other by standard train magnets.
The cabin includes the doors made in the original designed as seen in the video. However, I included a "drop-down" back door to allow a much better access to its interior which is fully decorated and has enough room for 2 or even 3 minifigs (including a chair).