Bowsprit alignment

Discussion in 'Boatbuilding' started by zulpas, Aug 29, 2009.

  1. zulpas
    Joined: Jul 2009
    Posts: 5
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    Location: Calgary, Alberta

    zulpas Junior Member

    How critical is the vertical alignment between the center of mast on cabin top (I don't have the mast yet), tip of the sprit and bobstay fitting?
    The bowsprit is 4" Sq. tube, there is 3" lower deck from frame "A" forward to bow. The longitudinal forces are transmitted to this frame and bollards.
    When I align the mast base and the sprit perpendicular to frame "A", the forward end of the sprit is about 5/8"-3/4" off against the bobstay fitting. I tried to maneuver it to align all 3 points by moving the aft end to port and forward end to Stb., however, I think it is more important to have the sprit square against the frame and in line with the forces. In this case the sprit is going to be visibly off the bow center. Am I being too fussy here?
     

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  2. rwatson
    Joined: Aug 2007
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    Location: Tasmania,Australia

    rwatson Senior Member

    I am having trouble imagining what the alignment problem is. In any event, having the Bobstay in alignment with the forestay is the most critical item on the agenda
     
  3. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    I don't think it's too critical (though I think it's a bit inelegant) for the sprit end to be a bit off. What about whisker stays? What about the fact that the jibstay puts a lot of lateral load on the sprit's end? That componant would be far greater than any slight offset to one side.
    That's what whiskers are for.
    The question is, why did it happen and could it be made dead-on by cutting some out of the frame? It would bother me just to know the sprit was off-center even if it didn't matter functionally.
     
  4. zulpas
    Joined: Jul 2009
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    Location: Calgary, Alberta

    zulpas Junior Member

    Thanks. The misalignment between the bobstay fitting and center of the sprit is actually only 1/4" on distance of 7'. I think I can weld the sprit end fitting off the center to make up the difference and perhaps position the whole bowsprit off the sguare to the frame, say 1 Deg.
    How it happened? I don't know, even having all framing restrained something must have moved during welding. The rest is all within 1/8", just the front 3'-4' are off a bit. As for the mast top and staysail is concerned, I am not sure how can anyone find thru alignment, with level and plum bob that is.
    I thing this thread should have been in rigging section, I'll see if I can move it.
     

  5. TeddyDiver
    Joined: Dec 2007
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    Location: Finland/Norway

    TeddyDiver Gollywobbler

    No worries..
     

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