I wanted to practice making gears with the Shopbot at NYC Resistor, so I chose to try a nautilus gear based on thing:27233 by MishaT. They work ok, although the gear profile is a sine wave rather than an involute gear, so the mesh isn't great.
Pocket cutting the small ribs with the ¼" straight cut bit was probably a mistake. I should have made thicker ribs and maybe used the ⅛" bit. The problem is that it takes 11 pases to do a 12mm piece of plywood.