I haven't used mass production before on wood hulls because I try to build something that no one else is driving In this case, that doesn't apply I agree on multiple sessions, but the prop, shaft, and stuffing tube are spec items and that saves us from building them. At $14, it's a pretty good deal anyway. The design of the ship also places the whole prop above the keel (even if only a little). Not having it hang down protects it some from hitting objects in the water that might break the prop. Been playing in sketchup with some ideas for printed gears for rotating a turret. Mark Jenks did some bang-up work on a small pulley system for rudders using 1/8" stainless steel ball chain; I might see if he can scale a pulley to where it can fit over a PVC pipe tube to allow rotates with that system.