Thursday, October 10, 2013

More sewing

In a publication called A Spirit of Enquiry Essays for Ted Wright 1993 there's an essay entitled Sewn Boats of the Indian Ocean; and Plate 20.3 shows a Saamish sewn boat in the village of Notozersk, Russia. As the Indian Ocean is no-where near Russia, we conclude that sewing and navigation are divorced skills.

Certainly sewing and arithmetic are divorced skills: I was so keen to get on with sewing the garboard strakes together that I didn't pay attention to how long the boat was going to be until I noticed that I was going to have to chop seven inches off the blunt end or the side planks wouldn't meet in the middle. Think you're stupid?  - Not as stupid as me.

I put the templates on the upturned Optimist and found that I was short of quite a lot of area. My boat was going to sit quite a bit deeper in the water than I hoped.

Mr. Dierking's solution is to bolt a box in between the ends, extending overall length by quite a bit. Having plenty of offcuts, I thought I'd glue some 7mm thick side-plank extensions on to restore my missing 14 inches.

Out with the router: machine a 2mm deep strip at one end of the extension, offer it up against 4mm side plank, wonder why 2mm is standing proud, realise 7mm minus 2mm does not equal 4mm, wonder where brain was this morning, say usual word, put head momentarily in bucket of water, machine 2 more mm off, now have flat surface when the two are touching.

I mixed up some epoxy and having now read the Epiglass instruction PDF, simply put bricks on top of them because I'd just read that the epoxy sticks better if it's a millimetre thick rather than a squozen-thin layer of glue.

They were left for 36 hours partly because it's cold and partly because I had a bicycle fork to replace. And with the broken fork in mind I didn't want any stress concentrations so afterwards I set to work feathering off the over-glued parts, and it's a good job I did because quite a bit of it had no glue underneath. It merely looked glued. This joint is going to be in the middle of the boat, the point of maximum strain. I do not want it to break. I put a flap-wheel in the drill and ground away everything that wasn't glued, firmly resolving to be careful when applying fibreglass tape afterwards.

Next to sewing, and back to the original plan of standing the thing upright, dodging round it like a damsel round a maypole as I tried to poke the monofilament three times through a 2mm hole. That wore a bit thin and I got John to help, and when he wore a bit thin I finally tried a needle and wished I'd done so before because then it was quite easy. The nylon won't go through the eye of the needle any more than a camel will go through a rich man, but I found that tapping the nylon with a hammer flattened the end and then it did go through, and the nylon jammed in the hole and didn't work free so I was much pleased with myself. Four metres of nylon does mean you have to take your shoes off or you're always tangling things up.

I found the only way to keep the stitches tight was to sew it with the side planks open, like a tryptich.

Eventually I had to tackle the curve.

And to make the curve easier, I used the copper wire as a temporary fastening, heating it red hot to anneal it because otherwise it's too stiff and breaks on being twisted. The final stitches were 'stremely difficult, and I might have to think a bit more about this for the other end.

Pleasingly, the two curves matched, though there is a transition point. The side plank sits on the outside of the pointy end of the garboard strakes, and actually makes a neat join.

Moreover the sides struggle with my imperfect woodworking fit, and needed some gentle coaxing with a broken kitchen knife to transish at matching points on each side.

But where the sides sit on the top of the middle bit of the boat's garboard strakes, they slide down inside the boat, leaving a sticky-outy-ledge on the outside. I shall carve lots of tiny wedges and hammer them into the lashings inside the boat, and hope and pray that they squeeze the side-planks outwards to make a smooth outside edge.

Finally I sewed the ends of the sideplanks together, and coming to the bottom found a vast cavernous gaping hole which will have to be plugged with teased-out chopped strand mat glass fibre.

It can be the back end of the boat.

I expect it'll be all ugly and lumpy and make all the boat-builders wince inwardly but who cares? The front end can be pristine and glorious and beautiful and sharp and slice through errant jet-skiers like a scalpel, making all the swimmers happy. Swimmers hate the jet-skiers. They always ignore the 200 metre buoys and come ploughing inshore at full speed. Actually everyone hates the jet-skiers, even the jet-skiers themselves. I've often watched them. A huge effort to launch the craft, ten minutes driving pointlessly round in circles too far off-shore to entice the applause of an admiring throng. Then they come back to the beach a bit shame-faced, squirting out two-stroke fumes before switching off the engine and trying to round up parents and grandparents to pull the ghastly vehicle out of the water onto a boat trailer. Bit of luck the eventual oil crisis will deal their death blow.

Labels: , , ,


Post a Comment

Subscribe to Post Comments [Atom]

<< Home