So I really liked Polymathic’s Marvel Coasters (https://www.thingiverse.com/thing:3269260) and agunski's Avengers Keychain Collection (https://www.thingiverse.com/thing:3784003) over on Thingiverse. I thought “yes those, but fridge magnets”.
They also inspired me to upgrade my Ender 3 v2 to Jyers so I could use the filament switch command, so that was nice too. I made the ones I did since i had the appropriate colors, feel free to experiment with other ones too. I uploaded a blank base with the magnet holes, so go nuts.
I needed to print mine with rafts, since the small magnet hole circles just would not stick to my bed. YMMV of course.
I used 5x3mm magnets from Amazon (https://www.amazon.com/gp/product/B08M3H4VP5/) and after some experimentation made the holes 5.2 mm for a bit of tolerance. They were a good friction fit and I tapped them in with a hammer and nail set to be sure.
The color swap was at layer 21 without a raft and 25 with one (using Cura standard raft settings).
The only one that needed supports was the Avenger’s magnet so the A could properly hang out of the circle.
Enjoy!
The author remixed this model.