Desktop Marble Run

Basic components for a desktop version of a classic toy. I use ballbearings from an old bike wheel, which are about 6.5mm in diameter, but anything between 6mm and 7.5mm should work.

It is best to print the pieces laying on their sides as shown in the photo, with supports enabled. You don't need a lot of support, but it makes the end result fit together better. You might need to clean up the tops of the pillars if your print is 'messy' at all, but with the right slicer settings you don't need to.

UPDATE Dec 2018 - Added a new piece called Support Short that lets you make stronger towers.