This is the whole train assembled, and exploded, it only shows the left side because the right side is completely identical.
Axle peg
This is the axle peg that connects the wheels to the train. Notice how it is threaded to work as a screw.
Train wheel
This is the wheel that connects to the train. It has the section where the linking bar attaches.
Hitch peg
This is the peg that would connect one car to another on a train. This is in the back of the train, and sometimes is hard to notice.
Linking peg
This is the peg that connects the arm to the wheels, notice how it has a wide diameter, yet a small base.
Hitch Magnet
This is the piece that the Hitch Peg, slips through to be inserted into the Train, itself. This was a really simple piece to make.
Stack
This is the stack that inserts into the top of the train. (On a real train, this is where you see the smoke coming out.) This is a really complicated piece with lots of angles and dimensions, but in the end. it come out looking really cool.
Linking Arm
This piece is what connects the two wheels to each other so they move together, it goes on top of the wheel, then the linking peg, holds it in place.
cow Catcher
This is the piece that goes on the front of the train. It is a really complicated piece that required lofts,(Look in CAD pieces page to find out), and precise angles.
Train Body
Finally, this is the initial train body that everything is built around to fit. It looks complicated, but actually is pretty easy, I started with a brick, then just Extruded/Cut the shape around the circular column in the middle.