Is this 3D model free to download?

Yes, Harmonic Drive is free to download from Thingiverse. Open it in the free Thinger app, or use the "Download from Thingiverse" link to open the original listing by the creator.

Where do I download the STL file?

The download is hosted by Thingiverse. Use the "Download from Thingiverse" link on this page to open the original listing and grab the file, or save it to your print queue in the free Thinger app.

Designed by emmett, published on Thingiverse. Please credit the creator when sharing your print.

Can I print this at home?

Yes. This is a printable 3D model intended for home FDM and resin printers. Check the original listing for suggested print settings.

Harmonic Drive 3D printable model by emmett

Harmonic Drive

Source: Thingiverse by emmett

The Harmonic Drive is a free printable 3D model from Thingiverse by emmett. This is a 94.5 : 1 gearbox that is entirely preassembled and requires no support to print. You can download the STL file from the original listing below and print it at home.

Open in Thinger (free) Download from Thingiverse

1,687 saves Source: Thingiverse Updated 2026-10-28 License: CC-BY-SA · commercial OK 7 makes Category: Vehicles & RC

Tags: customizer, flexible, Gear, gearbox, machine, openscad, preassembled, reduction, supportless

About this model

This is a 94.5 : 1 gearbox that is entirely preassembled and requires no support to print. It is a type of harmonic drive, which uses a flexible output ring to attain a high gear reduction. My design is unique (as far as I know) in that it also incorporates a planetary gearset for further reduction. Instead of a toothed belt for the flexible coupling, I use a crinkled shape that forms involute gear teeth on both the inside and outside. The edges of the teeth taper down in order to keep the belt from stretching. The herringbone teeth keep all the gears from falling out. You can see a description and demo here:

Frequently asked questions

Is this 3D model free to download?: Yes. Harmonic Drive is free to download from Thingiverse. Open it in the free Thinger app, or use the "Download from Thingiverse" link above to open the original listing.
Where is the STL hosted?: The download is hosted by Thingiverse, not by Thinger. We link you directly to the original listing by emmett.
Who made this model?: Designed by emmett, published on Thingiverse. Please credit the creator when sharing your print online.
Can I print this at home?: Yes. This model is intended for home FDM and resin 3D printers. Check the original listing for suggested print settings like layer height and supports.