The centerboard needs two layers of fiberglass, so we start with a layer down from the top a few inches so we can lap the fabric over the top of the board - as shown here.
My first fiberglassing job was earlier, on the insides of the centerboard trunk. This turned out ok, but not as well as I had hoped. So, naturally, I turned to Mr. Google for help.
I found a really good article by Ted Moores on the West System site - this really helped me do a much better job on the centerboard (the article is here)
Here all three edges are covered with it, with two layers on the bottom.
It was pretty easy to work with - took more epoxy to wet-out than fiberglass, and has a much finer weave. (I got this from Jamestown Distributors). After the epoxy is cured, when you (try to) sand it, it is really hard.
Then, I thought about the stresses that will be on the upper part of the board, hanging from that pivot pin, and being pushed sideways by water pressure. That fiberglass butt joint started looking kind of weak to me. So, since I am getting so practiced at fiberglassing, I went ahead and put a 3rd layer of fiberglass over the top (flat) part of the board - you can see the bottom extent of the 3rd layer here. I did lap this layer over the top of the board, so we have 2 layers of fabric on that edge now.
You can see how much the board weighs from the bend in the 5/8" rebar it is hanging from. Makes it easy to work on both sides in one go.
So, I now need to apply at least one more fill coat - this time will be thickened epoxy. And then roll on probably a couple of coats of epoxy with graphite powder. Using graphite allows me to avoid painting the board to protect the epoxy from UV, and hopefully makes it less likely to get stuck in the trunk (we'll see about that....)
Meanwhile, all parts needed for the initial assembly (bulkheads 4-7, seat longitudinals, centerboard trunk) are epoxy coated and I am working on sanding them. Very soon, I will be clearing stuff in the shop and assembling the building jig. Woo-woo!