After sending the kids to bed it was time for some more work on the trunk. I am adding the uprights (pieces of wood) that attach to frame 3 to the middle of the centerboard trunk. I also have to attach the pieces that hold the two sides of the centerboard trunk apart. This allows room for the centerboard to swing up and down inside the trunk. The centerboard is up for trailering, shallow water and when using the motor and down when sailing. The centerboard keeps the boat from being pushed in the direction of the wind. Sometimes called a foil, the centerboard pushes on the water, which resists the push, and allows the vector components of the wind direction to push a sailboat forward. In simple terms. the centerboard allows the skipper to sail into or across the wind, instead of just following the wind's direction. Anyway, enough physics, back to building. I finished all the prep work while the kids were reveling in their after dinner joy, so all I had to do was glue and screw (and nail.)
Putting the pieces together was easy until I split one if the inside spreader pieces. There are 24 nails in that piece alone, so I should have known the wood would split. Luckily I found the split before the epoxy was totally hardened. I filled the gap with as much epoxy as I could jam in there. Here is the frame three upright. Frame three attaches to the back of this piece.
If you look closely as the lower right side of the picture you can see the hole for the centerboard pivot. Still to be completed is fiberglassing of the inside of the trunk.
Then I will nail the other side to the spreaders and the trunk will be complete!
Frame two is the second from last (aft) frame and attaches to the back (aft) end of the trunk. Frame three is in the middle of the trunk, I hope I lined it up right. Frame four attaches to the front (forward) end of the trunk. In all, the centerboard trunk spans 51 1/2 inches of the boat's 180 inch (15 feet) length. I have a feeling that finishing the trunk and attaching those frames will NOT make me 1/3 of the way done.
Do you pre-drill the nail holes ? I had to with Oak Frames. It should help prevent splits.
ReplyDeleteI pre-drilled a few. The nail diameter is so small that you need an extra small bit to leave anything for the nail to bite into. I broke three bits before I switched to only drilling the really thin pieces. My solution was to use fewer nails and space them out better. If I notice a part that looks like it's not contacting (no epoxy squeezed out) I put another nail in. I think that where I split the wood I used too many nails, even though 25 was what was called for.
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