Spinning Sphere Inside Sphere | Print-in-Place Fidget Toy

This 3D-printed fidget model features a sphere inside another larger windowed sphere. The inner sphere has just enough room to move freely, letting you spin and rotate it within the outer shell in a couple of different ways. For the best visual effect, I recommend using dual-color or tri-color silk PLA, or any co-extrusion filament, to really make the inner sphere and surface patterns stand out. The included 3MF file has all the recommended settings already dialed in, so I strongly suggest using it to save time and get the best results. If you prefer using the STL files, be sure to center and merge the inner sphere and outer shell in your slicer before printing. You’ll also want to tweak the settings for each part individually. Just a heads-up: don’t expect long spin times. There’s some friction between the parts, and the inner sphere almost never prints perfectly round. But that’s not really the point. It’s more about tactile interaction than smooth, continuous spinning. You could theoretically print the outer shell in two halves and the inner sphere separately (also in halves) using variable layer heights for a smoother result, then glue everything together. I haven’t tried this myself since the goal here was to make something print-in-place. FDM Print Settings I Used (Bambu Lab P1P): • Nozzle: 0.4 mm • Layer Height: 0.2 mm • Infill: Outer shell uses 10% gyroid, inner sphere uses 5% gyroid • Supports: Automatic Snug Supports • Top & Bottom Layer Patterns: Archimedean Chords If you prefer using the STL files, be sure to center and merge the inner sphere and outer shell in your slicer before printing. You’ll also want to tweak the settings for each part individually. If you have any questions or run into issues, feel free to reach out. I'm always happy to help. Enjoy the print! 🌀 Also available: I have a similar model that features an octahedral shell instead of a sphere. If you're interested, you can check it out here: https://www.thingiverse.com/thing:7281018 License Information: This model is licensed under Creative Commons Attribution-ShareAlike (CC BY-SA). You are free to share, copy, redistribute, and adapt this file for any purpose, even commercially, as long as proper credit is given to the original creator. If you remix, transform, or build upon this model, you must distribute your contributions under the same license as the original. Selling physical prints of my other designs is only permitted if you are an active member of my Authorized Seller tier on Patreon, Printables, or MakerWorld. To learn more, visit https://www.patreon.com/c/endlessdesignlab Thank you for downloading and supporting Endless Design Lab! 🌀 Endless Design Lab has many more mind-melting models to be unveiled! Please show your support by following me on your favorite platforms. https://linktr.ee/EndlessDesignLab 🤝 Want to collaborate? 📧 Email me at [email protected]