Course Correction

With the rack and pinion setup in place, I hooked up the control lines for a trial run. I was ready for the satisfaction of an easily flopping rudder. However, upon testing the setup a few observations were made: 1. the rack required a tremendous amount of linear force to move the rudder; 2. the open end of the rack housing allowed the rack to pull away from the pinion gear when force was applied. The similar setups I'd seen in the SCR showed full housings for both the rack and the pinion gear. And they used bellcranks and brass rod to transefer the force to move the rack. Now I know why. My configuration, though sound, would require some modification.

While I chased the new varaibles through my head, an old notion came back to me: why not try an extremely short control tab mounted on the shaft linked to a conventional pushrod? I'd done this in my 1/96 USS Thresher which has a pretty confined tail cone. It would be easy enough to knock together and would settle that particular idea for good -- one way or another.

After a few hours in the shop the end result was a new keyed upper rudder shaft with a small control tab. It's width was dictated by the upper rudder fin dimension. A brass shaft hooks into it via a z-bend and the wheel collar connects it to the nyrod pushrod. Talk about keeping it simple!

A pull on the nyrod control link inside the hull and the rudder answers to port.

A push and the rudder answers to starboard.

The next trick is to finish the upper rudder fin, pour a mold, and cast an new GRP piece. Then everything can be fine tuned to fit inside. However, at present everything is within design parameters and fully functional. Once I figure out the best way to post it I'll have a short video of everything in action.