Roller Fidget

***Updates***02-15-25 - Refined the shape a bit to better capture the metal bearing. It works! Next steps are to start over with the shape, but with the second form-factor (see 3mf file, plate 2) in mind. The ball rolls so smoothly, that I thought it'd be nice to have another bearing installed beneath the ball to serve as a second fidget. ----- Original description ------This is a (very small) first prototype of a fidget idea. I love the feeling of a weighty ball rolling around in my hand. I was reminded of this recently, and put together this proof-of-concept. This uses an 18.25 mm steel ball. I also included a sphere as a downloadable file, in case you don't have a proper steel ball. Note: this is a FIRST PROTOTYPE. A list of items I'm aware of: Ball does not remain captive; it'll fall out if turned upside down.It's just too doggone small. Maybe some more, but I plan on adding updates as time goes on. I'd like to add a 608 bearing under the ball to provide ano