Assembling the Centerboard Box

My hardware arrived today and I want to get teh centerboard box in place asap. I glued, screwed and bolted the centerboard box together this afternoon so I can prepare to mount it tomorrow.

Painting the Inside of the CB Box

With the headledges screwed and glued in place, it is time ti get the inside of the CB Box painted before I assemble the 2 sides together.

I am using an Anti-fouling paint that contains Cuprous oxide or copper powder suspended in the paint. It is a heavy can and the copper will discourage marine life from growing onto a surface, copper being toxic to most living things.



The paint requires almost constant stirring to ensure the copper remains suspended in the paint.

It goes on thick and I have taped off the area where the other headledge gets glued so that the surface remains clean.

Attaching the headledges

Another glue and screw operation.

Attaching the Sides to the Bedlogs

I began gluing and screwing parts of the centerboard box today. I went slowly to get it right. I piloted holes for some 16 or so silicone bronze wood screws tro hold the side panels and bedlogs together.

I understand tat you should no countersink plywood but there are times when it cannot be avoided and this is one of those times.




I mixed a batch of glue, slathered it on to the 2x6 and waxed the screws, sinking them by hand with the bit brace.



It turned out right and tomorrow I will do the other side!

Shaping the Centerboard Box

I love power planers! What a time saver it was. In a half hour, I trimmed her down to the lines that I took off the keel curvature.



I had about 1-1/2" to remove in the forward part and 3/4" of wood to removed in the back and what would have taken me at least 4 hours was accomplished in 30 minutes!



Gotta love it!

Assembling the Centerboard Box

I cut 2 pieces of marine plywood and cut 2 pieces of 2 x 6 and added two 1 x 2-1/2" pieces of pine to form the centerboard box. The 1 x 2-1/2" pine go on either end to provide a space to fit the pivoting centerboard in.


The plywood panels assembled with the pine end pieces.


Cutting the 2 x 6's

After checking for the initial fit of the pine board to the plywood, I added the 2 x 6's to the form to complete the mock up for fitting into the slot I had cut into the keel.



I had already removed frames 5, 6 & 7 in order to be able to lift and place the keel box. I had chiseled and rasped the openings to widen and square them a little more to get the right fit.



Placing my hydraulic lift under the center of the box, I lifted it into position, plumb with the face of frame #4.



This is not the final position but serves to illustrate the concept about how I will now transfer a parallel curved line of the keel to the sides of the 2 x 6's to allow a nice watertight fit against the keel. I will shave that down with the power planer.

More on that in the next installment!

Cutting the Centerboard Slot

The centerboard is lowered when the sail is raised. It is a piece of wood that project 2-3 feet below the bottom of the boat and is there to resist the force of the wind from pushing the boat sideways. Sort of like the tail on an airplane, it helps track the boat forward.

I have made a 3/4" wide opening along the center line of the keel. This will be the first step in the construction of a "box" to contain it when it is in an upright position.

It was a fairly easy operation. Drawing the limits out in pencil, I plunged my circular saw into the wood and cut it from one end to the other.



I finished the cut with my hand saw then used my saber saw to cut the ends.

Shaping the keel

I began to work on the keel today. I laid out the batten along the keel slot and marked the position of each frame. I then transferred the frame locations to the keel board. I marked the width of the keel at each frame and laid a batten along these marks to make a curve for the keel shape.

I then took my saber saw and slowly cut the excess wood off from either end. A quick pass of the power planer squared and smoothed everything and it turned out great

Now I will wet it and, putting 2 blocks (cat is optional) in the middle, put some curvature into it to make it easier to set it into the boat.

Cutting the Keel

A simple but significant step today as I cut the board that I chose for the keel to its maximum width.

Next I will recheck all the frames and make sure they are plumb and fasten the bow stem into its final position.

When that is done, I will take a batten strip and mark the location of each frame. The batten will take the effects of curvature into account. I will mark the location of each frame on the keel board and lay out the taper of the keel.

Building the Foundation and Setting the Frames

Busy day today. The plan was to build the cradle or foundation, then square and level it. I had 2 14-foot 2x4’s for the sides and sliced a 2x4x8’ in two for the ends. The work went quickly and I figured why not start in on the setting the bow stem into position?


The foundation

After marking the center of the foundation at both ends, I cut two 1-foot 2x4’s and shimmed them to be level with the foundation and attached them with deck screws. Taking the bow stem and placing the 48” ruler to mark the forward most point for the stem, I took the angle of the stem from the full size drawing and set it correctly, making sure it was square and dead center to the foundation. A hefty 6” clamp will hold it in place.



That went pretty quick too so on to marking out the positions for the 10 frames and the transom. These were double-checked for accuracy by comparing measurements from the front and back of the foundation.

With this done I wanted to see if I could get a couple frames mounted. First, I had to run a mason line to use as a centerline. Measured it out and attached it then I put up frame number 1. I used a plumb bob to align it with the centerline then sank a couple deck screws into the spreader to hold it in place. 2 drills, one for pilot holes and the other as a driver, made quick work out of mounting the frames to the foundation.


3 frames done


5 done!

It went so quickly that I got all 10 and the transom set!





I am going to bevel the frames in place with an electric planer and we will see how that works!