I’m building a robot that somewhat resembles R2D2 - a round body with a spinning semi-sphere head - NOT a clone for copyright reasons and deep respect to the filmmakers! The robot’s spinning head needs a large, thin bearing.

I have tried searching for a bearing like that to purchase - those are not easy to find, costing around $1000! Therefore, I have looked into making a DIY bearing like that. Thankfully, this bearing would not have to carry much weight or move around much. Therefore, this type of bearing can be 3D printed.

Long story short, I have designed and 3D printed a small 60mm OD bearing as a starter prototype - and it worked great! So, I leveled up to 190mm OD, which also worked well. Finally, I have printed a 340mm (13.3 inch) OD bearing on my DIY Voron 2.4.

Here is a YouTube reel illustrating the concept.

And here is a complete from-scratch tutorial for absolute beginners showing step-by-step how to design a radial bearing in Autodesk Fusion 360 (free for personal use as of the time of the writing), 3D printed on my glorious Voron 2.4 350mm (and my old reliable Prusa MK3S) and assembled by yours truly using 1/4” steel bearing balls I purchased on Amazon.

After posting this video on Reddit and Facebook I got (harsh) negative replies saying that 3D printed plastic bearings are of no use. I do beg to disagree. After extensive testing, I can recommend 3D printed bearings for use in light-duty applications including pan-and-tilt hardware - cameras, lights and R2D2-style robot heads. More specifically, the larger your light-duty bearing is, the more money you can save by 3D printing it istead of purchasing one (made from steel). Moreover, thanks to 3D printing you can make your large bearing of just about any custom size you want - as long as the bearing fits your 3D printer.

I printed my bearings usint PETG plastic. If you want to level-up from very-light-duty to something more durable, consider using Nylon, Nylon reinforced with glass beads or Delrin (POM-H) self-lubricating plastic filament.

Last, but not the least. There are radial bearings and there are axial load bearings. My DIY bearing tutorial shows the former, while your specific use case may need the latter.

Happy 3D printing!