I’ve been wanting to do this for awhile, and finally got around to trying out an elementary movable print-in-place item, emmett’s gear bearing on Thingiverse.
I did these using some Photocentric3D Firm resin that I bought and pigmented myself. My first two tries printed, but were frozen in place because I didn’t use enough pigment. I upped the pigment concentration to about 0.8% and got a working part out.
I was initially too conservative and printed it with a 0.4mm clearance, making the parts a bit too loose, especially since the Photocentric3D Firm resin is kind of rubbery. They also make a Hard grade resin that would probably be better suited for this purpose.
Which also mean with a bit of squishing, I could also take the individual gears out:
A subsequent print with 0.25mm clearance functioned better:
Here’s a video of it moving: