This is a replacement engine for the popular Dominos game “Mexican Train”.

My wife wasn't happy with the injection molded engines that came with the set she bought, so I modeled this engine to replace those tiny, poorly made pieces.

I liked Eclsnowman's design, especially his integration of the brush guard to the front wheels and that it has good surface contact to help the print stick to the bed.  While I appreciate how Eclsnowman put soft edges on every corner of his design, the printed result, in my wifes opinion, lacks detail.  At the scale of these pieces, none of my printers had trouble with overhangs so chamfers are, IMO, unnecessary.

I printed these at .2mm resolution with 100% infill to give them some weight.  I integrated the cow catcher with the front wheels like Eclsnowman's model, but extended it further forward and added a long wide structure that connects the front and rear wheels to increase surface contact of the bottom layers so these would print easier on bare glass, which is the surface on most of my printers.  The result allows me to print this on multiple machines in different colors without switching filaments, and with no need of a brim, nor supports. 

It's my intent to print Eclsnowman's hub exactly as he made his using black as the base and silk silver for the tracks as that looks so much nicer than the crappy plywood hub that came with my wifes set.  Whether or not you decide to use my engine, be sure to check out Eclsnowman's model first and please give him a like:  https://www.printables.com/model/258438-mexican-train-dominos