A small locomotive with the cylinders on one side.
About this creation
This is really a caricature of a shay locomotive, it only has one truck, and is completely disproportionate to a real one. It's technically an eight-wide, but I run it with my six-wide collection and it doesn't look out of place.
View of the left side, with the "saddle tank" hiding the drive wheel.
The gear train that powers the pistons. The rubber wheel touches the top of the flange on the rear left motor wheel.
It may look not look like it from the side, but this thing is horribly chunky. Notice in this picture grab irons at the back, lamps, domes, a whistle, and a minifig-size cab. You may also notice that the rear axle is awfully close to the center. To give it more balance and better pulling power, there's a hollow inside the boiler filled with ball bearings. I know, I know, not real Lego. I just didn't have any weighted 2x6x2s at the time.
Nice engine, but to make it more realistic you could make it a 2truck,2 cylinder shay. How to do this? I figured to take off the 3rd cylinder, make a small tender (with an axle and only one coupler) ,take off the back coupler on the engine and connect the engine axle and the tender axle with a u joint. If you have never heard of lego u joints, type lego u joint on the ebay search bar. Of course, it is already fine how it is. Just a suggestion.