Thursday, September 16, 2010

Leeboard

On to the leeboard and bracket... The leeboard is carved out of a solid piece of white ash, beautiful stuff.  I used the method I read about on Duckworks Magazine and it worked perfectly.  After routing off the majority of the material, I smoothed out the router bit marks with the random-orbital.  I wanted some extra reinforcement, so I added two strips of uni-directional carbon fiber on each side.  Then to smooth everything out, I put on a thin layer of epoxy + phenolic micro spheres, then sanded nice and smooth.  As you can see, I still haven't gotten around to painting it... still a little unsure about the color, help me decide by voting in the poll on the right side of the page --->

 
The leeboard isn't much use without the bracket.  It seemed to me that the loads on the bracket could be pretty substantial, so I built it pretty beefy.  It is made of 3/4" stock, 4" wide with 2" tall sides; creating a U-beam of sorts...  The pivot face is glue and screwed to one side, with 1/4" thick triangular reinforcements.  The main body of the bracket is covered with a layer of carbon fiber, and all joints on the pivot face are reinforced with fiberglass and carbon fiber.

 
The bracket is held to the XCR thwarts with two "L" shaped wood blocks (carbon/kevlar reinforced) that are tightened down with 1/2" stainless steel bolts and handle nuts. The bolts go through slots cut into the bracket, so that I can move the blocks in or out depending on their position in the boat.  This allows me to adjust the center of lateral resistance and find the best position for the given conditions.



 
The leeboard pivots on a 1/2" stainless steel bolt, with large stainless steel "thumb" nuts.  These are relatively easy to loosen or tighten underway if I need to pivot the board up or down.  Thanks to McMaster-Carr for all this great stainless hardware, they have everything!  So far, everything has been working great!

1 comment:

  1. Sweet canoe. I voted for Red but it showed up as a vote for black so then i voted agian. Anyway, I say red. Looking forward to seeing you in the EC. I did it my first time in a homemade tirmaran also. If I could say only 1 thing about it, it would be that it was too heavy. Keep it light and you will thank yourself! Awesome job. www.sailnaway.blogspot.com
    -SOS

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