Freewheel Ratchet Fidget - Fully 3D Printed

Totally inspired by the freewheel ratchet fidget (by Need It Make It), this fidget toy has a pleasing clicking sound as you turn it. It demonstrates the engineering concepts of a ratchet and compliant mechanisms.
 

This is a redesign of my original model. The changes include:

• smaller ratchet teeth for a nicer sound
• integrated plastic thrust bearings for smoother turning
• better designed print-in-place hinge and spring.

Features of this model:

• only three parts
• no need for extra materials - all 3D printed with no screws or springs
• no small parts, no overhangs - easy to print
• demonstration of engineering concepts -  compliant mechanisms and ratchet.

The three parts go together in the obvious way (see the photos). The cap is a press fit, sealing the mechanism. Add a small dollop of CA glue if you don't want it to come apart.

When you first put the fidget together it may be a little tight. It should loosen quickly after a few turns.