My son loves his marble run set, but he keeps running out of parts before his imagination finishes.  I modeled up a few of the parts from his set, the drop tube, foot, and sloped pieces.  The trick was making them fit the injection molded parts, while still being able to work with the printed versions.  The layer lines made that tricky, I tried my best to make it work ok with both.

If there is enough demand, I may look at modeling up other parts from the set or even some ideas my son requests.

In the picture with parts assembled, the blue parts are the printed.  I don't want anyone thinking I am trying to pass off the glossy injection molded parts as printed.  I just wanted to show a mixed assembly.