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2.7.2 Making and Installing Rudder(s) and Rudder Stuffing Tubes
(By Bill Pickl)

Building the rudder assembly is relatively simple. First locate where the rudder shaft should be located and transfer the measurement from your drawing to your ship's hull. Next cut a block of balsa about 1" square and tall enough to go from the bottom of the hull to about 1" above the water line (or as high as possible). Take this block and sand the bottom contours so that it sits perpendicular in the hull. Then use a vice and drill press to drill a 5/32" hole down the center of the block. Then glue the block in the hull insuring the hole is correct location and the post is perpendicular to the hull. Now you can use a hand drill with the 5/32 bit to completely drill through the bottom of the hull. If the block is too deep for your bit a piece of 5/32 brass tubing with a roughened end can be chucked up in the drill and it will eventually cut its way through. This method is suggested since it is easier than trying to sit a battleship squarely under a drill press, however if your shop will support doing that it would be a quicker and perhaps more accurate alternative.

Next cut a section of 5/32 tubing that is a little longer than your rudder post block. Put a little CA glue on it and tap it through the wood support post. You will want to leave about a 1/16" of an inch above the post inside the hull and below the bottom outside the hull. Use a dremel to cut the tubing down if necessary.

Next cut an 1/8" solid brass rod the appropriate length for the rudder shaft. The shaft should extend ½" above the rudder support block (or higher depending on where your rudder servo is located) and the entire depth of the rudder below the hull. Test fit the shaft and check your measurements.
The next step is to cut out a rudder from thin brass sheeting. It should be thick enough so it does not bend easily, but not so thick you can't cut it with metal sheers. My favorite method is to use very thin brass and layout a pattern such that you will fold mirror image rudders around the shaft. The thin brass is easy to cut and the finished rudder has a more hydrodynamic shape.

Next file the rudder shaft flat where you will be attaching the rudder. You will only need to flatten on one side if you are using a one sided rudder, but on both sides if you plan to use the wrap around rudder. Put flux on the flat side(s) of the shaft and then use vise grips to clamp the rudder in place. Use a small torch or a 100 Watt soldering gun to heat the rudder and shaft and apply silver solder.
When installing the rudder you will need some sort of bushing between the hull and the rudder. If your ship's rudder is flush against the hull just use a small thin washer and slip it over the shaft then slide the rudder into place. If the rudder needs to stand off some distance then use a wheel collar to lock down the correct stand off distance.

The final step is to install the control arm. If your arm will be above your post you will also need a wheel collar to ride against the rudder stuffing tube. In most ships a simple lever that locks onto the shaft with a setscrew is sufficient, but for those really narrow sterns a toothed pulley and toothed belt can be used. The toothed pulley method works very well for the twin rudders in the narrow stern of a Scharnhorst. The belt goes around both rudder pulleys then around a matching pulley on your servo and you've got a quick and simple dual rudder drive. The caution is that belt driven rudders can slip easily if the rudder is bumped during ship launch or run aground when going in reverse, so use conventional control arms and wire rods where possible.

(Continued on page 23 )