The rudder is going to be a simple but big project. Another OYCOA member e-mailed a sketch and numerous pictures of his Nantucket Clipper's rudder, so I had an idea of what it's suppoesed to look like. The company that is constructing my rig was able to create and fabricate a stainless steel rudder post from the sketch and pictures I had been given.
The next decision was what to use for coring material. There is the traditional foam core, but I was concerned with how well I could manually shape it. There was also the option of marine plywood, however, a friend of mine that works in a marina recommended a new material called Coosa board that they've been using for coring material with great success.
I found a dealer in Annapolis, Oceana, Ltd., that had the board. The rudder sketch says it's 2" at center, and my rudder stock is 1 1/2". I ended up getting the 1 1/2 board to sandwich together for a 3" thickness.
So the plan was to carve out the inside of two sandwich halves to match up with the rudder stock, clamp it all together with 5200, shape the outside foil, and top off with a layer of glass before the final sand, barrier coat, and paint.
We laid out the stock on the board with rough plan, marked out key points with nails, and traced out the rudderstock shape onto the Coosa board. We purchased router bits to help with the carving. The Coosa is interesting stuff. It's not the lightest stuff in the world, but I don't think it's suppoesed to be. It was very workable, the router went through with no effort. Hand sanding was easy as well.