Modular NEMA 17 4:1 Helical Planetary Gearbox

thingiverse

Here is the rewritten text: I've designed a stackable 4:1 planetary reducer for NEMA 17 steppers, and I've tested up to two reduction stages - beyond that, the plastic may become too weak. To print this design, you'll need one of everything except for three secondary sun gears and six planetary gears. You can increase the number of planetary gears by adding more stages: three per stage is a good starting point, but you may want to add additional planetary gears as needed. Hardware Needed (per stage): Output Shaft: * 1x 608ZZ bearing * 1x M5x24mm round head bolt * 2x M5 nuts * 1x M5x10mm washer Carrier + Planetary Gears: * 6x 683ZZ bearings * 3x M3x20mm round head bolts * 6x M3x6mm washers * 3x M3 nyloc nuts (can be replaced with standard nuts and loctite or lock washer) Ring Gears + External Fasteners: * 6x M3 nuts * 4x M3x8 bolts Optional: * 2x M3x6 bolts * 2x M3x20 bolts Secondary Sun Gear (for multiple stages): * 1x M5 nut I also recommend applying a light coating of white lithium grease to the gears for smoother operation. Note: This design is intended to press fit onto a 5mm motor shaft with a 4.5mm flat ground on it.