Slim and Ultra-Slim Nema17 Gearbox 1:4 Ratio

thingiverse

***Update 2-14-21 This version should be the last one and is working for now. Ill update if it fails, or when I find premade metal gears and do a solid metal version. Props to Gemma Potrony and Josep Pencas for the very well made spur gears. The original files for the gears can be found in uploaded files.*** {E-steps you need to multiply your current steps by 4. Turn down acceleration to ***NO MORE*** than 17% of what it was. This applies to standard Nema17 motors and a 8-bit controller. If you have better hardware, then you can experiment further. You have been warned. Currently mostly tuned in except for compensating for resonance frequencies are: [Ender 3 Pro] 400 Axis steps per mm 3000-3400 Max Feedrate mm/min(If you havent changed much in Marlin and have a stock board) 100 mm per second Max Acceleration 0.4 mm per second Jerk ***Video of it in action(excuse the crappy camera setup) https://youtu.be/hA449_jcm3E*** Update 2-13-21 -- New stronger gear version now available. I recommend this one for easier time printing, easier assembly, and stronger parts overall. Still no change in dimensions of the motor profile. Maybe a single mm I think extra. Mk.2V4 is definitely small. Absolutely no increase in motor dimensions at all. I recommend your best and strongest materials. Gears are 2mm thick, overall mod is 19mm. 0.1 tolerance so sanding will be required for free spinning gears. I recommend thread lock on the Sun gear(the blue one) to secure it to the motor shaft to prevent slip under heavy acceleration and braking. New e-steps should start around 1600 steps/mm. Last version had strength issues with the carrier. Also uploaded a carrier for 8mm shaft/screw/rod adaption. Just whipped up a concept idea of a extremely low-profile 3d printed upgrade for all Nema17 motors. The gear ratio is 1 to 3.7. I have to do testing to figure out the end ratio since I do have 20 tooth pulley that I didnt factor with the planet gear system. I designed to be as easy as possible, but I still recommend 0.1 or 0.2 nozzles and take it slow. Resin printing will shine here. I will make a version with a 8mm screw and a standard 5mm shaft. At a later point when I can secure a resin printer sometime. Otherwise print the 6 parts and install like the pictures. Sanding may be required, I only put in about 0.2 clearance/tolerance. Nylon may be better to print the gears since they need to spin freely. ***A word of caution! On any axis installed on you need to recalibrate e-steps for about 3.7 times more than what you already have it at. Ender 3 Pro runs at 400 steps/mm so a good place to start would be 1480 steps/mm. Have adequate cooling on that motor since its spinning more than 3 times faster than you would normally have it. 8 bit boards might have problems since they can only handle so much processing. Klipper will help keep up print speeds while increasing the quality with this mod. V-ref may need to be adjusted.*** Props to Let's Print for the handy video on designing gears. Their page is over here -> https://www.youtube.com/channel/UCLn_0VPipeMkLqo5tW6FP0A Some more testing of the gearbox under its own steam. https://youtu.be/8Sn-LYkH3vo