The Lifting Rudder and Centerboard.

While proceeding with step by step gluing up the decks and combing, I was also designing and making the centerboard and rudder. I read a lot and looked at many pictures and found there were two main solutions: either the rudder was fitted to a shaft set in the stern, or it was hung outboard on the stern. I decided on the more straight forward on-stern attachment and found two secondhand gudgeon fittings originally meant as sailing hardware. The first gudgeon screwed directly to the top of the stern, and the second to tapered pieces of hardwood through bolted and glued to backing plates inside the canoe just above the waterline.

A friend gave me a quarter inch thick piece of aluminum out of which I first cut the centerboard shape and then with the remainder glued up a composite wood and aluminum rudder blade which would pivot up and down at the base of a laminated plywood rudder stock. The most difficult problem for me to solve was finding a pintle to fit both the gudgeon and the thickness of the shaft. No such animal! Eventually I took two galvanized nails, cut off their heads, and bent them the to a 90 degree angle in the vice. After carefully lining everything up I drilled two holes into the leading edge of the rudder shaft, applied epoxy, and pushed the cut nail ends into the plywood. The bent ends were angled down and the whole rudder hung right away so that every thing could be finely adjusted before the setting glue made every thing final. I now had a rudder whose blade could lift if it touched ground, which could be raised by a lanyard to any degree including a vertical position (if I wished to row backwards), and which could be lifted completely off. The nail pintles were of soft iron so that under extreme shock they would simply bend rather than break themselves or the rudder stock.

As the canoe would be impossible to steer with a tiller ( too far back and with a mast in the way)I decided to use a cross piece( yoke) at the top of the rudder shaft to which tiller lines could be attached so the canoe could be steered from anywhere. This too was designed to be removable if needed.

The centerboard case had been built for a one half inch wooden centerboard, but the quarter inch aluminum had obvious advantages: it was not buoyant and was abrasion resistant. Unfortunately it was too thin for the width of the case. I solved this problem by gluing quarter inch plywood to the sides of the aluminum and then faring the whole thing to a streamlined taper at both edges with the belt sander. I coated it all with an epoxy/graphite mix. The centerboard was then wedged temporarily into place in it`s case and a hole drilled through case and board for a bolt on which it would pivot. Besides being a tight fit, the bolt had rubber washers at either end to prevent any leaks. A wire was attached to the top of the centerboard and lead through the top of the case so the board could be raised.

It was difficult to estimate just how large the rudder blade should be so I made it large and plan to trim it as I start using it. Too large a blade will be awkward and strain the rudder stock and too small would be ineffective. It is all part of the fine adjustment process that is built into this style of design and construction.