Forestay tang clashing with anchor...

Discussion in 'Sailboats' started by Roly, Feb 5, 2014.

  1. Roly
    Joined: Jul 2005
    Posts: 508
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    Location: NZ

    Roly Senior Member

    I want to mount my fairlead anchor roller center and kinda like the look of this
    as opposed a "witches hat" triangle above the channel.
    I am wondering what potential distortion and resultant headstay tension loss could occur. 34' sailboat displ. 6 tonne.
    Schedule tube approx. 80mm dia x 100mm long.
    Any thoughts appreciated.
     

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    Last edited: Feb 5, 2014
  2. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Roly; That is an attractive layout but I have some reservations about its adequacy.

    Consider a triangular weldment with the chain fairlead ensconced inside the triangle. The fairlead will bear none of the forestay load. The forestay to be attached to tangs atop the triangle. Put the welds in shear mode as opposed to tension mode. Do use only a certified welder whose credentials are impeccable. Either of these methods must be certain that the attachment to the stem or sprit is beyond question, nay bullet proof.

    Losing the forestay can be a deadly event both to the boat, the rig, and the occupants of the boat.
     
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  3. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    Sounds like the tube is about 4" long. A 1" long half-diameter of a slightly larger tube welded atop the tube in the drawing would be very strong if you're worried about deformation. And the triangle idea is sound, although maybe not as good looking.
     
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  4. Roly
    Joined: Jul 2005
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    Location: NZ

    Roly Senior Member

    Thanks guys-Food for thought.
    I am going to go as drawn, but up the tube to 7.62mm wall & 2205 ss which has twice the UTS of 316L. Monitor closely for deformation. (with calipers) & probably with backup tether. Weldment will be the weakest link.
    If it doesn't work, I will revert to triangle.
     
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