I have made two modifications to the trunk, though very minor. One is a modification, the other is simply a change in sequence from the manual.
Drill, Fill, Drill : When building Thister and I would drill through an epoxy-filled hole, the diameter was often not large enough for me to avoid drilling back into the raw wood. I would then have to re-seal the hole with epoxy.
I have seen this in other blogs, and I will do the same. I will drill all my epoxy-filled holes a little larger than plan. For the centerboard trunk this is the hole for the knot of the uphaul line as well as the hole for the centerboard pivot.
Sheave Shims : In the manual, it appears that these are installed after the trunk is glued up. As many other builders have done, it makes much more sense to me to install those shims before gluing the sides up and then having to work in a restricted space.
The construction of the trunk is straightforward. Cutting the spacer pieces along the dogleg is the only part that could be considered tricky. At this point I have glued up my centerboard and I found it helpful to lay the centerboard down on one of the trunk sides and sketch around it so I could see where I needed clearances. I lined the centerboard’s pivot hole with the hole in the trunk side and then made the bottom of the board parallel with the trunk bottom. Particularly, this helped me make sense of how spacer #2 (my notation, not CLC. see pics below) needs to be cut. Though it seems obvious in hindsight, I was originally placing spacer #2 such that is covered 2″ of the board instead of the intended 1.5″. Which means I was confused about how the curve at the joint of spacers #2 and #3 was supposed to happen. Once I saw where the centerboard HAD to go, it made sense. Seems obvious now.
My surface has three coats of epoxy but isn’t as smooth as I would like. I have a few fisheyes that need filling in. So I will add another epoxy coat with microballoons (to both inside faces) and then 3 coats on the inside of the trunk blocking. After that I will glue up the trunk.
After gluing the blocking onto the first side of the trunk, the squeeze out makes it a little difficult to square up the second side. To make sure both sides are aligned I drilled a nail sized hole in the center of my pivot point and sheave bolt location. After dry fitting the second side I dropped nails through the two holes to get the two sides lined up with each other. Then with a straight edge, I made pencil marks at various locations along the outer edges for reference when things get to sliding around while gluing.
When the second side is glued, epoxy will squeeze out on the inside of the trunk. This needs to be cleaned up so as not to leave something that would cause the centerboard to jam. The manual recommends wrapping the end of a stick with a towel soaked in denatured alcohol or the like.
What I have found is helpful is to first scrape out as much epoxy as I can with a dry stick with a beveled edge. Otherwise, the soaked rag ends up simply pushing around almost as much epoxy as it removes. So I first scrape with a dry stick, then use the rag for cleaning the tiny bit left.
(I should have made my stick out of something besides scrap particle board. Can’t get a nice clean edge.)
Trunk is now glued up and cleaned out. Left to do is sand the outside edges and do some rounding on the edges that will be exposed in the cabin.