Fitting The Gunwales

[msueirro]

Things have been moving along pretty well. The hull is wired and tack-welded and knees are fitted and installed at the transom, but I'm having some difficulty with the next step. I've scarfed up two pairs of 1X2's into two long boards for use as gunwales. I've had them pre-fitted to the hull to set in the proper bends in advance of actually attaching them, but when I do that the boards curve up as I go to the stem. I know that they are supposed to do this, but they curve up to the extent that they meet each other at a point above the sides. I find that I can force them down so that they maintain a rate of curvature that matches the top of the side panels, but then there is a large gap at the underside of the gunwales. They just won't make the compound bend, which is no real surprise.

The question is, what have I done wrong, and how do I fix it? The dimensions of the side and bottom panels are correct to the plans, at least within a sixteenth or so. Nothing that should account for this discrepancy. Any suggestions?

Mike

[JeffM]

I'll bet the gunwhales on my cs20 didn't have to bend as much as yours do, and I had the same sort of gap on an early dry fit. I ended up (for unrelated reasons) with gunwhales that were thinner and narrower than spec, and I found that I could fit them pretty easily.

[Joe Nelson CS#35]

Lots of screws and clamps should pull in the gap.

[Howard]

I think it ultimately does come down to clamping pressure. A little hear, a little there. Half turns up and down the line and eventually it works into place. It also will depend on what type of wood you are bending. Some work better than others.

I'm sure there is a technique for this specific operation. I had the same problem with the Spindrift, complicated by having three strips to laminate at the same time. They kept sliding apart. For that, I wound up clamping blocks to the line I wanted the bottom of the strips to end at, then clamped down to those at the same time as bending the gunnel strips to the hull. Getting them to lay down at the bow took enormous clamping pressure across some part of the lamination, which of course forces the epoxy out, creating a weak bond.

I recently found this trick that I would use for this type of clamping job:

http://www.messing-about.com/forum/viewtopic.php?t=4487

This will take considerable clamping pressure and still hold the glue in place.

I'd also let the job sit under clamps for at least 5 days to let it cure. If you let up too soon, it will pull apart.