I have been doing 3D printing at Shapeways also! for the transmissions I found some of my project if I place more then one piece in a print it's sometime cheaper. I put them on a spruce and have 4 or 8 at one time! here is example, I did one Omni Mover and it was $6.00 for just one. I then did another Drawing with 4 Omni Mover and They were only $10.36 now that is a big differents almost half price!
An HO scale gas station I designed and 3D printed on my home printer. Design and construction details can be seen at http://nvrr49.blogspot.com/2016/11/gulf-gas-station-ho-scale-3d-printed.html
