I received the hardware today and 3D printed and laser cut the parts. I realized the layer lines would look better it if were printed on its side, so I will tweak the design to work better in that orientation.

The gearing inside works great. However, the speed limiter is not needed. The lever arm is strong enough that you simply don't get any extra resistance from the limiter, and you can also alter the overall resistance by tightening the axial screws. It is also a pain to install, so I will drop that from the design. The potentiometer fits nicely, but needs to use super-glue and so I am going to see what I can do to make it fit more reliably.

The detent sort of works, part of the issue is the inaccuracy of FDM 3D printing, combined with the layer lines. I think if I want a middle detent that it will have to be some much larger mechanism. I got an idea for that using laser-cut delrin that will be easier to tweak and dial in to the right feel.

The ball and steel rod are so heavy that you have to have it screwed down or magnetically attached to something to move the lever. So as a desk toy it won't work unless the base is made heavier. I may make the final baseplate using 3/16" steel from sendcutsend.com.

I think I will still put in the longer 5.5" rod, as the 5" rod still feels a bit short even though it matches most of the the on-screen photos.