This is my entry in the Carbide 3D Community Challenge #14 "Gears". A machine whose only purpose is to circulate ball bearings in a fun and loud way. If you want the original c2d design files, please look in this link: https://community.carbide3d.com/t/community-challenge-14-2019-2020-edition/26395/30
Conceived 2 days after the contest was announced, it’s been a crawl/walk/run/mad dash to get the project, glamour-shots and video done by the deadline. Having never done gears, I thought they would be the hardest part, but they turned out to be relatively straightforward using a free online gear generator (link below).
The hardest part was getting the marbles to load, not fall out on the ride to the top, and then dump out consistently at the top. Gravity keeps them in place for the ride, because the gear rack tilt back 4 degrees. Then through trial and error I machined “divots” on the inside edge so the marbles fall out at the top. [Note: The “better” way is to drill the marble holes on an angle with a Forstner bit in a drill press. But who wants to use a drill press for 30 holes when they have a CNC???]
I had no particular plan. After successfully getting the lifter mechanism working, I just made it up as I went, adding on stick-by-stick until all paths led back to the start.