Gears 17t to 39t. You can make whatever ratio you want.

thingiverse

Consider joining in if my work inspires you. Just ask if you have an idea for a custom gear piece you'd like to see created. As the title clearly states, design your own version of the gears. This pack includes all the gears from 17t to 39t. I've only thoroughly tested a handful, but they're all crafted with the same specifications as the gear generator, so they should function flawlessly. Print settings: Layer height: 0.1, initial can be 0.2, but you'll then get a small elephant foot Perimeters: 12 (just to ensure it uses only lines, no infill) Speed: 20mm/s https://www.youtube.com/watch?v=gTumwM-vLK4