I refurbished my centerboard 2 years ago, and have had no problems with the method I used. I ordered a stainless steel pin about a full inch shorter than the width of the stub keel at the pivot point, in order to leave about a half inch at each end. I ground out the last half inch of the hole on each side to create a rough cone shape, then filled it with thickened epoxy and smoothed it over (after installing the board, of course!) No problems since, whatsoever. It's kind of hard for me to imagine that this could ever get knocked out be the forces normally applied to it. Of course, if you are talking about *sealing* the holes, epoxying over the outside is part of it, but you still have the holes inside the slot. What I did is, before installing the pin, I drilled out the entire hole about 1/4 inch larger diameter than the pin, coated the inside of the hole with thickened epoxy, and re-drilled to the exact diameter of the pin. Then I also put a thin film of fresh epoxy in the hole as I was installing the pin. One other tip: I put large, thin nylon washers in on each side of the board -- I don't know if they help in any way, but my thought was to 1) reduce friction at that point when lowering/raising the board, and 2) center the board and reduce side motion/wobble of the board. So far so good, 2 years and maybe 30 sails later. If you all are really good, I'll tell you about the valve/flap I fabricated and installed in the cockpit drain while I had the board out. It keeps my cockpit floor almost completely dry even in the nasty chop of Lake Michigan!