Adjustable rudders

Discussion in 'Multihulls' started by Fanie, May 18, 2008.

  1. Fanie
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    Fanie Fanie

    Can one make a rudder you can adjust deeper or shallower (like a daggerboard) ?

    I know you get some that swivel aftward like when they get hooked onto something but I'm thinking up and down...

    The advantage would be twofold - you can have a smaller rudder in shallows, and it could be easy to replace a rudder in case one gets damaged.
     
  2. Doug Lord

    Doug Lord Guest

    Sure, my first foiler had one(same one on my new boat as well) ;so do the Bladeriders, RS600FF foilers and some beachcats...
     

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  3. Fanie
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    Fanie Fanie

    Retractable rudderboards
     
  4. Fanie
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    Fanie Fanie

    You sure that thing floats Dough :D

    I have seen those foils on some boats, but never had the oportunity to experience them for myself.

    Do they make a big difference ?
     
  5. Fanie
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    Fanie Fanie

    A search on the forum and googling for 'retractable rudderboards' came up with no results :mad:

    Does this not exist then ?
     
  6. Doug Lord

    Doug Lord Guest

    Maybe I'm not understanding you. The reason I posted the picture of my rudder was because the rudder blade retracts vertically in a "trunk" similar to
    a daggerboard trunk. Same on the other boats I mentioned. A line can be rigged to retract the rudder from the cockpit or lower it from the cockpit.
    The picture of my rudder shows it about 60% retracted. The reason you see this system on some boats with t-foils is because a pivoting system for a t-foil is extremely complex.
    If by "rudderboard" you mean "rudderblade" then that is what retracts in the systems I'm talking about.
    Hope that helps.
     
  7. Doug Lord

    Doug Lord Guest

    ===================
    Rudder t-foils work well on some boats; see this thread:
    http://www.boatdesign.net/forums/showthread.php?t=22262&page=2
     
  8. deepsix
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    deepsix Senior Member

  9. masalai
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    masalai masalai

    The GBE 29' cat uses lifting rudder blades - seem to work OK but doubt they will "lift" of encountering an object as they are designed to break the bottom third off if significant impact...
     
  10. Fanie
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    Fanie Fanie

    Thanks everyone so far. I'm throwing a few ideas around regarding this.

    It would be nice to have retractable rudderblades that can be replaced... but I don't like the idea of it breaking off on impact.

    The kickup could have it's own challanges if you try to steer in shallows...

    Could a conbination of the two be done ?
     
  11. deepsix
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    deepsix Senior Member

    1 person likes this.
  12. Pericles
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    Pericles Senior Member

    Gunboat 48 rudder.
     

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  13. Pericles
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    Pericles Senior Member

    Gunboat 48 rudder. Possible shapes?
     

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  14. Meanz Beanz
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    Meanz Beanz Boom Doom Gloom Boom

    Have they proven that shape works well Perry?
     

  15. Pericles
    Joined: Sep 2006
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    Pericles Senior Member

    MB,

    The whales would have given them up if they didn't! :D :D The indentations on the leading edge improve the stall characteristics.

    Perry
     
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