Traveler Position challenge

Discussion in 'Sailboats' started by mbrault, Dec 29, 2010.

  1. mbrault
    Joined: Dec 2002
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    Location: Montreal

    mbrault New Member

    I am finishing a complete restoration of a SANTANA 39. My plans are to integrate a full enclosed cockpit (using a custom arch and canvas). In order to do so, I will have to relocate the traveler of the main sail to a different location.

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    Now: The Main sail traveler is located (longitudinal) 3/5 of the boom right in the cockpit (seat level). The sheets, traveling from the traveler to the boom are right in the way and prevent any "encapsulation" of the cockpit.

    Solution 1: Position the Main Sail traveler on the roof portion of the boat (move 4 feet forward) which would then be approximately 1/4 of the boom length. (attach-point on the boom being relocated accordingly)

    Solution 2:I am building an arch that will be positioned in the rear of the cockpit. I could integrate material and additional structure support to accommodate the Main Sail traveler. The position of the traveler would then be located a little behind the boom (attach-point on the boom being relocated accordingly)

    Question A: Although I would prefer to go with option#2, I have serious concerns about the effect of elevating the traveler (which is a fixed component) vs being low (originally)? Would the boat be less steady / performent sailing to weather?

    Question B: On solution 1, considering the lever effect of the boom (attach point being moved forward), Is it a bad idea to add such stress on the roof, or would it acceptable considering proper reinforcement of the boat in that area?

    Thoughts and ideas are welcome! Thanks
    email: mbrault@konsultech.com
     
  2. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    Engineering ? Hard to say...the farther forward you move the mainsheet the higher the load on the boom and mainsheet system. Perhaps your boom is strong enough..perhaps your cabin house is strong enough.

    As far as performance...depends on the length of the traveller. Boom end travellers must be very long...rail to rail ...in order to maintain leach tension. A midboom travellor can be much shorted and still allow for leach tension over a wide arc. You might get better performance from a mid boom setup . Do you sail with a boom vang ? Many modern boats completely eliminate the travellor and develop leach tension with a very powerful boom Vang.

    Also ...the simplest formula for cleaning up your cockpit and avoiding cabintop or boom reengineering might be to recut the mainsail...raise the boom outboard end up enough to mount your mainsheet traveller on the aft arch you have constructed. You might loose a bit of sail area but the overall system would be superior and more user friendly.
     

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  3. Joakim
    Joined: Apr 2004
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    Location: Finland

    Joakim Senior Member

    Elevating the traveler has no effect on stability. It works better than a lower one while the boom is above the traveler, since you have better control of the side vs. down force on the sheet. If it is very close to the boom, you may not be able to get the sheet tight enough in all conditions. Also the down force on the sheet becomes almost zero when you let the boom further than the end of the traveler.
     
  4. kenJ
    Joined: Jul 2005
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    Location: Williamsburg, VA

    kenJ Senior Member

    Almost all Hunter sailboats built in the last 15 years of so have arches with traveler integrated into them. Might want to take a look at them for some ideas. They may even have one that will fit on your boat, might be cheaper than a custom build.
     
  5. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    I think that you should build an arch that is positioned forward of the end of the boom. The traveller can be installed on top, and it will work as a boom crutch.
     
  6. mbrault
    Joined: Dec 2002
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    Location: Montreal

    mbrault New Member

    I was planning of using a strong Boom Vang anyway, but it seems like I am getting lots of valuable input here. Thanks all for contributing.
     

  7. CutOnce

    CutOnce Previous Member

    One thing to keep in mind is that the further out the boom you place the traveler, the less purchase you need on the mainsheet blocks, as the lever arm is increasing. This helps offset the longer mainsheet issue somewhat as you may be able get away with a 1:2 (or whatever) where before you had a 1:4 (or more) mainsheet purchase arrangement.

    In dinghies we often have split bridle rear boom mainsheets that feed forward to a central block which routes the mainsheet back down to the cockpit. The split bridle at the rear can be further enhanced to allow controllable "traveler"-like function by adjusting the "tails". Boom end travelers in dinghies basically require a very strong vang to maintain leech tension and sail shape when the boom is outboard.

    Problem with full width travelers is they are only effective maintaining leech tension and sail shape when the traveler blocks can be close to directly underneath the boom - further outboard and the vang becomes necessary.

    --
    CutOnce
     
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