I saw something like that on thingiverse but without the outer ring. I also havent got the right bearings so I desiged my own PlanetaryGearSpinner.
I like planetary gearboxes very much and i like how they perform. I put 40 M3x10 ISO4762 in the outer ring to use ist as a flying wheel. Try it with air pressure but make sure you wear protective goggles.
The inner screw is a M3x20, the 3 screws in the planetary gears are M3x16.
The bearings are in the middle two 16x8x5 mm and on the outside 3 standart 608ZZ with 22x8x7 mm.
Play around with the horizontal expansion parameter in Cura to find out a suitable value for your printer and your material. I would start with -0.05 mm.
Keep printing.
Print Settings
Printer brand: Creality
Printer: CR10S PRO
Rafts: No
Supports: No
Resolution: 200
Infill: 50
Filament brand: SUNLU
Filament color: Purple + Black + Silver
Filament material: SILK PLA Plus
Credits:
MatthiasEberhard