6812 (60×78×10 mm) 3D-Printable Bearing – Uses 6 mm Airsoft BBs

his is a fully 3D-printable 6812 deep groove ball bearing designed to use 6 mm airsoft BBs as the rolling elements. It’s meant for light-duty applications, experiments, or just as a fun demo of how bearings work.

I’ve tested it in PLA, PETG, and nylon. All work, but PLA and nylon roll noticeably smoother than PETG. A small amount of light PTFE or silicone grease makes a big difference in reducing friction and wear.

Printing & Assembly Tips

Tolerances: The raceways are sized so 6 mm BBs fit with enough clearance to roll freely. Airsoft BBs can vary a little, so expect best results with higher-grade ones.

Print orientation: Print the races flat on the bed for maximum roundness and strength. Try to position layer seams so they don’t end up inside the raceway.

Infill & walls: Go strong – 80–100% infill with 4–6 perimeters is recommended.

Lubrication: Use PTFE or silicone grease (avoid petroleum-based greases, which may degrade PLA/nylon).

Durability: PLA is fine for light loads and demo use, nylon is best for strength and smoother rolling.

This model isn’t a replacement for a real steel bearing, but it’s a great functional print to play with, test, or use in projects where a traditional bearing isn’t needed.

EXELENT TO USE IN Spirographic WDT TOOL for 54mm.