Sunday 17 February 2019

Tiller done, board ballast

I took the tiller home and gave it four coats of varnish, hanging over my bath tub. In the end I decided that the quick-release cleat for the down-haul was too big for the tiller, and also probably unnecessary. I went with a simple jamb cleat.
The white webbing is the attachment for the main sheet block. It's held on by one screw and washer on the underside of the tiller.

Board Ballast

I had the idea that since the board was solid foam and thus very buoyant, I ought to weight it somewhat, as I wanted to lessen its effect on the boat's trim. I found the area of the foil section (roughly) by taking a scale drawing and filling it with rectangles and triangles whose areas I calculated. I multiplied that by 40" to find its volume, and worked out that it displaces about 16 lbs of water (the board is 48" long, and I expect that 40" in the water would be close enough to average).
John had given me a chunk of lead which I weighed and found to be 5¼ lbs. I thought it felt very heavy, and that I wouldn't want more than that. To make sure, I tied the piece of lead in a bag to the board and threw them in the water at a dock. The board floated very high, so I'm okay: it won't sink to the bottom! 😀
That foam is very tough stuff. Maybe you can see the glass hairs everywhere in it. I had flattened the lead somewhat by whaling on it with a hammer. As usual, I didn't take a photo of the final part, darn.



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