We gasped when we saw the new mechanism — a total of 15 rack and pinion linear actuators that ... [Gurpreet] melted servo horns to down to their hubs rather than trying to print something ...

The pinion fits a trimmed servo crank arm, the mating rack is stout and stiff, and early backlash problems have been solved. The whole case is easy to assemble, and as the video below shows ...