Soprano Ukulele Concealed Worm Gear Tuners

Based on my previous headless gourd shape ukuleles, but instead of using off the shelf tuning pegs, I designed these 3D printable tuning pegs that is completely concealed. This design allows the unit to stand upright on its base like a vase, and no tuning pegs that will scratch the right arm while you play.

The body and fretboard can be printed with a large FDM printer, while the worm gear tuning pegs should be printed with SLS nylon due to the high precision and strength requirements. Also instead of using my own printer, I use services like TreatStock and 3D Hubs to print the unit in the photos.

If you decide to print this design, you will need a printer that can print 400mm in the Z-axis which is the length of the neck+body.

Like my previous design, a rectangular carbon fiber rod should be used. In this design it is inserted into the body all the way from the tail into the neck.

FYI I bought these rods from Dragon Plate. You should get a 24" long piece and cut it down to about 390mm. If you don't use a rod, the neck will bow under string tension.

How I Designed This

I use OnShape's scripting feature to code the logic to generate this parametric design.