“Optimist: Someone who figures that taking a step backward after taking a step forward is not a disaster, it’s a cha-cha.”
With all the bulkheads and assemblies on the building jig, it was time for the chine logs and sheer clamps.
Here, wide boards of Douglas fir are being scarphed on the CNC. I have used a 1 in 12 angle as I did with the plywood. In addition there is a very shallow groove for a spline to stop the pieces slipping during glue-up. The wide boards were then ripped to width before gluing because I can’t get 30 foot lengths through our saw!
Chine logs in. In section these end up as a rhombus with 40mm sides. The plans say you ‘may’ make them up as two thinner layers. I’m extremely glad I did, even using Douglas fir. Who wants a fight to the death with a piece of wood? It’s certainly not how I’m used to working. Heaven knows what it would be like if using mahogany. This picture shows the first layer of the chine logs glued in.
Here, the first of the sheer clamps is installed. In contrast to the chine logs, these are installed whole. Being only 25mm thick, this is not unreasonable and indeed the bending forces were not too bad – though again, I would not have fancied it with a stiff hardwood. However, we did find that to make them land successfully at stem and stern, a good deal of twist had to be applied – more than you could do without mechanical assistance (in the form of a clamp attached to the end to act as a lever).
DISASTER! Everything clamped up fine, and I spent about an hour admiring our handiwork and thinking about next steps, before locking up and going home. Everything was OK when I left, but coming in next morning I was greeted with this sight – the sheer clamp had broken in two places. Somehow it had just given up the struggle in the small hours.
It has got me slightly worried that there is something wrong with the Douglas fir I bought, but testing samples of it to destruction – not very scientifically, I admit – suggests it is just as strong as I would expect. Maybe it was all to do with the twist rather than the bend.
It has been well said of Barnaby Scott by those who enjoy his close acquaintance that if there is one quality more than another that distinguishes him, it is his ability to keep the lip stiff and upper and make the best of things. Though crushed to earth, as the expression is, he rises again – not absolutely in mid-season form, perhaps, but perkier than you would expect and with an eye alert for silver linings. (With apologies to Wodehouse, P.G.)
There being not much else for it, we pressed on and removed the offending item before fitting both new ones as double layers like the chines. They now seem solid as a rock and no hint of further trouble.