This reproduction of a 1492 Columbus wooden clock stopped working years ago and I could not repair the damaged pinion with the mold-and-epoxy method.  I could not find anybody would could make a new wooden pinion. It was really frustrating. But my son said he could reproduce the pinion with his 3D printer.  After taking the dimensions and entering the data in his computer program, he was able to produce the piece we can see on the attached picture.  I put the clock back together and the clock is now running.  It is not a reliable time piece but it makes me happy to hear it tick –although the beat is not even.