not worth a whole lot. But if you and I were having a few beers I would propose this.
I'ld scrap this clamshell idea because the glassing is so difficult. If I could have 'seen' into the problem with the models I made, I don't think I would have continued. Once I was welding the rudder I was commited.
A take apart rudder is a good brain exercise. Agreed? If NO use yer curser to exit NOW.
Here, instead of clamshell, let's just cut it across like a loaf of bread.
I would simply make a top half that socketted into the lower half. If you can imagine two straps (1/8" thick, 1 1/2" wide bar) coming off the sides of the shaft and meeting at the trailing edge, you have a long narrow triangle. Make this at the top of the bottom half. It is hollow in there.
Make the mating part of the top half out of the same material but smaller so that it fit snug inside the long narrow hollow. That's a lot of bearing surface. You could have the shaft fit into a self socket also. Might even be four sided, male and female. Maybe that's over kill. Maybe the shaft could merely be cut there, conceptually. Actually the rudder is two separate pieces.
You'ld have a removable fairing piece on the boat or the top of the rudder that would allow the two pieces to be separated, by lifting the top part up. The bottom half would be lifted out of the shoe, and the top would be slided out of the tube. Would the keying of the mating parts have to be any more than two inches deep? Don't think so, And the fiberglassing would be a breeze. I would run it by a structural engineer. Wish I'ld thought of this befor. Beelieve I'll have another pint with my friend here, anybody got a pencil?
But, do you even need the continuous shaft at all? Need the top for the tiller head, need the shaft thru the rudder tube, need the connection down at the shoe. What do you need the middle for? [need something in the middle for the gudgeon strap keeper]
The original rudder, you need the full/split shaft. But with epoxy and glass and welded flat bar the middle part of the shaft is useless extra weight! The original did not have a continuous shaft. An aperture in the rudder might present a minor design adjustment.
1" silicone rod goes for around $30 a foot. Manganese rod is available.
If I had the time...............
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