Video can be found here: https://youtu.be/d8us3OWgS1A STL and Editable Fusion 360 source files can be found here: https://bbprojects.technology/collections/stl-fusion-360-source-files/products/3d-printable-high-torque-servo-gearbox-version-2-files This servo/gearbox is the new and improved version of my original gearbox design (https://www.thingiverse.com/thing:3292860). The original one had a gear ratio of 30:1 and the speed of the output shaft was about 715 RPM which made it difficult to tune in the right PID parameters. This new version has a gear ratio of about 162:1 which lowers the speed and increases the torque of the output shaft. I choose to go for double helical gears on this one because they produce a lot less noice than regular spur gears and the forces on the teeth are transferred more gradually. The gears rotate around a 6mm stainless steel shaft which is lubricated with bearing grease. Ideally all the gears should have some bearings, this is being considered for the next moment. Unlike my previous design I used 2 20mm bearings to support the output shaft. The servo uses a 775 36V 9000rpm brushed DC-motor which is driven by my Universal Morion Controller (UMC)(https://www.thingiverse.com/thing:4245315). The stall torque theoretically is about 297kg/cm, I was able to test the servo to a torque of about 132kg/cm. During testing none of the gears broke, they were all printed in PLA. The weak link in this design however where the mounting tabs and the bevel gears used in the first stage on the motor shaft. These 2 gears tend to slip under high loads ,like when i tried to pull the car forwards with it's handbrake on, but this didn't occur when i performed the test where it pulled 132kg/cm of torque so it should be fine to at least this torque rating. Video can be found here: https://youtu.be/d8us3OWgS1A More info can be found here: https://hackaday.io/project/173854-3d-printed-high-torque-servogearbox-version-2 Components used: 11 × 3D printed components Can be found on Thingiverse 1 × 775 brushed motor link: https://www.banggood.com/775-Gear-Motor-DC-12V-36V-3500-9000RPM-Motor-Large-Torque-High-power-Motor-p-1091058.html?p=E01411629100201406T1&custlinkid=255143 1 × M3 Bolt and nut 30mm dimension: 30mm lenght, Used to secure the small possition feedback gear to the 20mm shaft 1 × Universal Motion Controller Another project of mine used to control and drive the servo: https://hackaday.io/project/170604-umc-universal-motion-controller 1 × heat shrinks https://www.banggood.com/328pcs-Heat-Shrink-Tubing-Insulation-Electrical-Shrinkable-Tube-Sleeve-Cable-21-p-1362019.html?p=E01411629100201406T1&custlinkid=669227 2 × 6mm stainless steel shafts link: https://www.banggood.com/681012mm-Diameter-550mm-Length-Linear-Rail-Shaft-Rod-for-3D-Printer-p-1533105.html?p=E01411629100201406T1&custlinkid=1206718 7 × screws 30mm lenght dimension: 4.5mm diameter, 30mm lenght, Used to mount the lid 2 × 20mm inner diameter 6004 bearings (20*42*12mm) link: https://www.banggood.com/Deep-Groove-Ball-Bearings-6000-60052RS-High-Speed-Bearing-Steel-p-942862.html?p=E01411629100201406T1&custlinkid=1206865 2 × Screws 15mm lenght dimension: 4.5mm diameter, 15mm lenght, Used to mount the motor 1 × 10K potentiometer link: https://www.banggood.com/5pcs-200V-0_2W-10K-Ohm-Potentiometer-Single-Linear-p-961348.html?p=E01411629100201406T1&custlinkid=1206871 2 × M5 bolt and nut 40mm dimension: 40mm lenght, Used to secure the big gear and servo arm in place Tools used: SMD rework station: https://www.banggood.com/YAOGONG-8878D-2-In-1-SMD-Rework-Soldering-Station-Hot-Air-Gun-Welding-Solder-Iron-Repair-Tool-p-1348341.html?p=E01411629100201406T1&custlinkid=1206705 Infrared digital thermometer: https://www.banggood.com/AKKU-Infrared-Digital-Thermometer-Handheld-Infrared-Thermometer-Industrial-High-Temperature-Thermometer-Laser-Temperature-Measurement-Gray-p-1595938.html?p=E01411629100201406T1&custlinkid=1179895 PLA filament: https://www.banggood.com/Creality-3D-White-or-Black-or-Yellow-or-Blue-or-Red-1KG-1_75mm-PLA-Filament-For-3D-Printer-p-1290153.html?p=E01411629100201406T1&custlinkid=926158 Recommended 3D-printer: https://www.banggood.com/Creality-3D-Ender-3-Pro-V-slot-Prusa-I3-DIY-3D-Printer-Kit-p-1346320.html?p=E01411629100201406T1&custlinkid=677427 Paypal: https://paypal.me/BrockenBrian Feel free to take a look at my other designs: 3D printable antweight battlebot: Bulldog: https://www.thingiverse.com/thing:4623536 SpaceX inspired edf rocket: https://www.thingiverse.com/thing:4606751 3D printed high torque servo/gearbox version 2: https://www.thingiverse.com/thing:4547703 UMC - Universal motion controller: https://www.thingiverse.com/thing:4245315 3D-printable Davinci catapult gift card: https://www.thingiverse.com/thing:4067668 Arduino controlled photogrammetry 3D-scanner: https://www.thingiverse.com/thing:3958326 Fully 3D-printable turntable: https://www.thingiverse.com/thing:3723618 RC FPV tank rover: https://www.thingiverse.com/thing:3587738 Fully 3D-printable wind-up car gift card: https://www.thingiverse.com/thing:3308710 3D-printable High torque servo/gear reduction: https://www.thingiverse.com/thing:3292860 'BOOM box' high voltage capacitor bank case: https://www.thingiverse.com/thing:2980012 Subby the interactive youtube subscriber robot: https://www.thingiverse.com/thing:2928254 robot hand || bionic hand prosthesis prototype: https://www.thingiverse.com/thing:2838239 3D-printable linear actuator: https://www.thingiverse.com/thing:2783959 Mini 3D-printable crossbow: https://www.thingiverse.com/thing:2710472 8 legged spider robot: https://www.thingiverse.com/thing:2470882 best 3D-printable bearing: https://www.thingiverse.com/thing:2349065 Have a nice day!

3D printable high torque servo/gearbox version 2

0.2mm layer, 2 walls, 15% infill