Shaping the Keel and Rabbet

Putting this much time into one piece of wood is unusual. I started with a new and fairly green 2 x 6 x 16' piece of air dried white oak. There was a natural curve to the board already and I wanted to take advantage of that.

Ripped to width

Shaped one end

The plans gave me the specs for the keel. They actually called for a two part keel, with a 3/4" board as the base keelson 5 1/4" wide, and topped with a 1x3. You can then cut the top of the 1x6 and the sides of the 1x3 to form the rabbet. Weeeelllllll.........

I found a good 2x that was 16' long when I was looking for wood for the stem. So I decided to go for a one piece keel and I'll likely need at least one more of those boards for the mast. The stem turned out solid, so now I have to start shaping the keel. I started by ripping it to width with a circular saw. The plans also called for a taper on each end. The aft end taper is wider than the forward taper with a constant width amidships. That makes it sound like I know what I'm doing.

I found the center of one end of the board and went out to the final width of the aft taper. Then measured up the length of the taper and made my cut. The plans gave a length but I wanted to fit the board to be more exact than that, so I then loaded the keel onto the frames to get my length.

This gave me the exact length of keel that I needed. Then it was safe to cut the fore taper.

Marking and cutting the rabbet is another story. The rabbet is a cut on the keel where the plywood attaches to form a watertight seal. I'm using 2 layers of 3/8" plywood, so the rabbet needs to be at least 3/4" deep. The angle on the sides has to change since every frame is going to come into the keel at a different angle. However I know that the top of the keel is a consistent width and I know what the sides of the keel are going to be, so it became straightforward to draw lines for the top of the rabbet on both sides. Then I made a shallow cut just to get an idea of the shape.

Teenager approved

I knocked off the corners with a power planer in that last pic. Just trying to remove that much material is not easy. Since the angle of the rabbet has to change over the length of the boat it can be very difficult to get it just right. The books say to take a chisel and hammer out the rabbet at the frames first, then work to clear out the space between the frames. I thought there had to be a solution with power tools.

Attached to the stem & first frame

This was a huge step. I didn't even do it right, but when it came together there was finally some solid connection. It started to look like a real structure. I ended up using a cordless circular saw to cut the rabbet , but I had to carefully measure the depth and cut it from both sides. Then chisel out just the part around the first frame and the stem.

getting it done!

Now that's a rabbet

Attached to the transom

After I got the rabbet cut out on both sides I attached the keel to the frames by cutting a notch into the top center of each frame the depth of the base of the keel and attached the keel with Titebond III and 2" copper screws. Turns out, the copper screws are very soft. Most of them did not make it all the way into the pilot hole. I need a ballpeen hammer to finish peening those off. But it's cut and attached now. I actually had to cut the stem off, shape it a bit more, and attach it again to get a watertight joint.

To the back

To the front

My what a keel

This really defines the curve on the bottom of the boat, and the rabbet should allow the plywood to fit flush and create a watertight joint with the frames. You can spend days shaping the rabbet and still not get it right, so I'm sure I could have done something cleaner. I'll refine it with a plane more when I actually get to put on some plywood. But there are a few more things to take care of first...