Compact Planetary Gearbox

thingiverse

This 40mm x 34mm planetary gearbox fits a NEMA 17 motor and has a 4.444:1 ratio (9:40 decimal-averse folk will love). Version 2 features an M8 bolt output by default, with no need to reprint the whole assembly for size changes - just print the top half of the planet frame and cover. For M6 lovers, print 'm6_output.stl,' while those switching from M6 to M8 use 'm8_output.stl.' Printing is tricky due to precision gear teeth, with 4 attempts yielding a happy result. Assemble, disassemble, and grease it after grinding away blobs. The 608 bearings are placed on the case's inside and bolt end, secured by nuts or locknuts. Slic3r settings were tweaked before printing at 20mm/min with a .35mm nozzle and .25mm layer height. Adjustable in .scad for different gear ratios, this work-in-progress is destined to drive an extruder. Needed vitamins: M3 screws, nuts, a set screw, 608ZZ ball bearings, and an M8 or M6 nylok nut.