With the boat looking like a boat, focus was turned to the rudder and daggerboard. I had previously glued the blanks for both using alder wood. The alder was cut into 1" strips and laminated together with the each adjacent piece flipped end to end and rotated 180 degrees to minimize warp. First step was to plane the parts. Thankfully I had a buddy with a nice DeWalt planer that was willing to help me out.
Once both sides are parallel and planar, the fun can begin. The design I chose was a NACA0012 with a 6" chord for the rudder and a NACA0009 with a 9" chord for the daggerboard. The plan was to use my table saw and cut down to the outer mold line of each foil. Using an offset table from one of many online sources, I created a spreadsheet that output the cut depth for each 1/8" step. This would leave a 1/16" wood fin between cuts. To ensure symmetry, the same cut is made on both sides of the blank. Here's the foil cross sectional shapes:
Rudder blank half way through cuts
Rudder blank with table saw cuts complete
After all the cuts were completed, I knocked out the wood fins to get down to the rough foil shape.
Then there was a bunch of sanding to perfect the shape.
Sanded rudder blade over vacuum bag material
Rudder over the carbon/glass cloth
Rudder after bagging and vacuuming/sealing in the bag
Once the rudder was unwrapped I sanded it down using 400 and then to 600 grit paper. A thin coat of epoxy was then applied over that. Finally, one last sanding to get it to something race ready. Unfortunately, I only had time to finish the rudder at this point. The daggerboard from the #73 Bad Hare Day (the wedge), wasn't the prettiest blade, but it would work for now. I needed to focus on finishing the bottom of the boat and putting hardware on the deck. Lots to do and only a couple months until the Midwinters at Gulfport!
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