Friday, March 18, 2011

A push-me-pull-you

I've read a lot of comments and debate about downhauls for this centreboard design. The connecting arm is quite short and I wanted to solve the potential problems of pushing a stuck board down, or even just holding it down when sailing beyond Mach3, but I wasn't taken with the idea of having cables inside the case. The extension arm should sort these issues, I hope. It has a rod and bush at each end and it slips away into the case when the board is lowered, with just enough sticking out to enable a line to be attached to a cleat, or even a shock cord loop to keep the board down. It is shown in these shots in the board up position. I guess I have to wait to see how well it works in practice, but it is good to use on the trailer! (and is probably another example of me over-designing simple problems into unnecessarily complex solutions)

6 comments:

  1. An elegant solution to an old problem. Well done!

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  2. I take it the board has no ballast? That's always my favorite way of keeping a centerboard down. But even then, the line for raising or lowering the board is a potential hazard.

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  3. Thanks for the input both.
    The board is quite a big, thick, heavy one, and has a fair sized lump of lead (dimensioned as per designer's instructions). The issue is in being able to push it down if there is weed or sand blockages, and keeping it down so that after a capsize it is out there to be stood on, or even just keeping it partially and accurately lowered on the wind.

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  4. I should also have mentioned that the case top swings up and can be raised by undoing a couple of bolts.

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  5. Rob, is that clear shrink tube used over a splice in the last image? (The centreboard line)

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  6. Yep...,well, white tube, instead of traditional whipping. We'll see if I can live with it, but it is tidy.

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