BareRotoMag

I decided to give a fidget toy with a bearing and magnets a try, inspired by INDX which looks super satisfying.

I used 608ZZ bearings (specifically these) and 6mm x 3mm magnets (these), parts which I already had around from other 3D printing projects and I am sure many others will have as well. I am also including the Fusion 360 files to adjust for your own magnets and bearings parametrically, if needed.

I tried a lot of variations on both the shape and the surface features. Ultimately I ended up with two shapes, bestagon (hex) and triangle, and a few surface features including smooth and dimpled. I printed and assembled something like 15 of these and chose my favorites to include here.

Printing

I printed everything with the flat side down and used “Snug” supports. You can maybe get away without supports, especially with some minor tweaks to the model. Let me know if there is interest in this!

Hardware

Inserting the magnets is the trickiest bit. I used some needle nose pliers for any that were particularly tight, but in most cases just pressing the print onto the magnet on a flat surface was enough. If it's really tough, you can adjust the magnet clearance parametrically in F360 or your XY compensation in your slicer to make the holes slightly larger (though this may have other effects).

Magnet Orientations

I played around with different magnet configurations and found a couple that I like. For both, all magnets in one piece are inserted with the same orientation.

On the other side, I used one of two configurations. The first leads to a clickier feeling, the second leads to a smoother feeling (surprisingly).

Standard Magnet Configuration

This is the configuration seen in the video above. I prefer this option.

(black indicates no magnet present)

Alternate Magnet Configuration

As seen here:

For the hex version, I also used all magnets in one orientation for one side and just three magnets in the other side, similar to the standard configuration above.

If you try something else, let me know! I'll probably upload a version of the model with holes above the magnets for easier experimenting (I just drilled mine).

Note: If you'd like to print this model commercially, please reach out to me on Printables and we can work something out. I don't expect much!