Tuesday 26 November 2013

Centerboard lifting mechanism

I decided to go a different route for the centerboard lifting mechanism. Basically it took us so long to finally have a small sailing boat with a potential fore "sunbathing platform" for my wife and I didn't want to spoil the dream by having taught ropes going across it.
In the original arrangement a 2 or 3 part block system is used to draw lines from the centerboard lifting point to the mast base.

In my version I will rather have pulley wheels fitted to the centerboard lifting point, to inside the forward log of the centerboard case assembly and on the deck at the base of the case itself.

Here's a sketch of the principle idea. The system of ropes is basically doubled up yielding a 4:1 purchase on the lifting effort. The lift line can be fed directly to the cockpit are or to a jammer on the side of the centerboard case.... no ropes fed to the mast step!


Here is how the implementation of the design look in a prototype set up. You can see the pulley wheels in slots routed in the case fore log. Also it should be quite clear how the system will eventually work.
For the moment it seems to be behaving extremely well and I am very pleased!!


4 comments:

  1. Lorenzo,
    That looks very good. The pulley system is neat and will keep everything tidy on the boat. Nice engineering.

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    Replies
    1. Hey Rik,
      thank you for your feedback which is much appreciated.
      I have dry fitted the case and the system works really fine. I will upload photos as soon as possible,
      kind regards
      Lorenzo

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  3. Thanks for excellent information.I needs to spend some time learning more or understanding more about wheels & circles.

    high tech rubber & nylon wheels

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