This step is conceptually easy, but harder to pull off. My lessons:
0) Don't even start this step until you've pre-bent the top deck in your rocker jig. When I finished my basement a few years ago, I put in a steam shower which came in quite handy - cranked to 130 degrees, the entire top deck got steamed for about 40 minutes and then was immediately clamped onto the rocker jig alone for a couple of days so that it had the rocker bend in place before gluing. Without that, it would have cracked and split as we raced to get clamps in place. Soaking hot towels on both sides of the deck would have accomplished the same thing - do both sides b/c if you do only one side, the whole panel curls. Don't leave wet towels on the deck after you clamp it. The wood w/the wet towel absorbs water and expands while other parts don't and bad things happen. Grain and others go about this differently, gluing individual deck strips to the ribs one-by-one so getting decking strips to take on the rocker may be simpler as you go strip by strip like building a strip canoe or kayak. My guess is that there are trade-offs with either approach. Visually, I like how I was able to use pretty broad panels of alternating cedar and ash with birch as the center stringer.
1) I glued a 2"x2" square piece of scrap decking to the underside of the top deck, exactly in the middle at 67.5" from the tail. This is reinforcement for the vent that will be epoxied into the deck. Some put their vent at the tail, mine will be 2/3's of the way up the board in the middle.
1) I glued a 2"x2" square piece of scrap decking to the underside of the top deck, exactly in the middle at 67.5" from the tail. This is reinforcement for the vent that will be epoxied into the deck. Some put their vent at the tail, mine will be 2/3's of the way up the board in the middle.
2) You want the centers of the top deck and bottom deck to be aligned as exactly as possible. I didn't assume my spar was exactly straight (it wasn't as it pressure from the rocker messed it up a bit) so I established an exact center for the whole assembly by matching the exact center of the top deck stringer and the exact center of the bottom stringer pieces (they aren't really stringers, but you know what I mean).
3) I'd been using Gorilla glue and decided to move to epoxy for this step. I underestimated how much epoxy was needed and couldn't run out for more as the clock was ticking. I reserved epoxy for the bond between rail, blocks and deck and used Gorilla glue for ribs and blocks on the ribs. I used 60 min epoxy so I'd have more time to get everything clamped down. My mistake was buying about 8 of the double syringe things from the hardware store thinking that'd be more than enough - it was half of what I could have used. Next time, I'll go to a marine supply and get cans of epoxy resin and hardener in bigger volume.Or, use marine epoxy that you dispense with a caulk gun (3M Marine Fast Cure 5200, http://store.grainsurfboards.com/products/extra-glue-pack).
4) The top deck of my board has a fair amount of curve from side to side - the 2x4s I'd used previously to hold things down don't bend much so I bought 1x2s that would bend as I clamped them - where they had knots, they broke, often violently as we really cranked them down. Luckily, neither my son nor I were impaled by a splintered 1x2 javelin. Even with increased bend from the 1x2s, we needed to jam shims under outer edges of the 1x2s to make sure that there was strong pressure all the way to the edge of the rails - I didn't want to take any chances with getting a good seal.
5) This operation needs more than 2 hands and a foot holding things down as you get clamps in place. My 15 year old son was critical in helping me get the clamps in place, shim them, etc.
6) I used every clamp I had - we counted a total of 53.
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