Apr 22, 2017

3D Printed DIY 1/16 Ratio Gearbox for DC Motors

Tomi Malkki made a 1/16 ratio 3d printed gearbox that he uses to modify torque and RPM of salvaged DC motors.

Project description with gearbox specs:

This gearbox has the ratio of 1/16. With this 12v motor it can lift around 3,5kg (straight from the shaft.) 2 washers should place between each gear (see details in video). It reduces heat between plastic parts when 2 washers are rubbing each other. Adding lots of bearing grease between everything is essential. Depending on your printer tolerances you might need drill out some holes bigger. Motor mount should be standard size.


  • layer 0.2
  • infill 25%
  • perimeters 3
  • bottom layer 2, top 3


  • Layer 0.3
  • infill 20%
  • perimeters 2
  • bottom layer 2, top 3

Here is the assembly video:

He also cleaned all the surfaces with oil and dirt cleaner, then added a layer of primer, 2 layers of surface paint and 2 layers of clear lacquer, he is using acrylic spray paints.

This is a very useful DIY project that can power many small projects like RC vehicles or robots.

All the files and instructions can be found at:


Thingiverse page: