The file '16mm Marble Robot Ballcaster 3D Printer Model' is (stl) file type, size is 1.5MB.
This part is an affordable robot 3rd wheel to make low cost differential motor robots.
You only need a glass/steel marble, the printed part and two couple M3 bolt and nut to mount this part on a robot.
The marble is inserted by a simple pressure. To extract the marble you can push it with a screwdriver through the top hole.
The distance between the two holes is 20mm.
16mm_Marble_Ballcaster.stl | 3.5MB |