swinging spreaders

Discussion in 'Sailboats' started by Mr.G, Nov 23, 2013.

  1. Mr.G
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    Mr.G Junior Member

    Does it matter if the spreaders on a mast are free to move fore and aft, or must they be restrained to stay square?
     
  2. michael pierzga
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    michael pierzga Senior Member

    Yes and no. If you bend a mast aft you will push the trailing edge of the spread into the mast wall.

    Do you sail with a flexible mast with much prebend ?

    It would be unusual to have swinging spreaders..normally there is slop fore and aft to accommodate normal mast movement
     
  3. Mr.G
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    Mr.G Junior Member

    Wooden mast spreaders

    I am replacing a broken wooden mast with another wooden one, and while I have the old mast fittings, was thinking about lighter and simpler alternative spreader base fittings.

    The mast is a single spreader fractional rig - with stiff fore and aft lowers, where there is no real for and aft or sideways movement.
     
  4. gggGuest
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    gggGuest ...

    It depends what you want the spreaders to do. There seems to be a bit of a fashion again for limited swing spreders in some racing dinghy classes after they went out of fashion years ago.
    If the spreaders can move then they are providing no fore and aft support for the mast, which may or may not be a problem. My instinct would be to have them fixed in place unless I was very sure I had a positive and planned reason in my rig design to make them swing. I don't think "Lighter and simpler" would reach that bar for me.
     
  5. michael pierzga
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    michael pierzga Senior Member

  6. michael pierzga
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    michael pierzga Senior Member

  7. Mr.G
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    Mr.G Junior Member

    thanks Michael and gggGuest

    Thanks Michael for the link to S&S that is a great resource.

    It seems that if the mast can be bent to make for a flatter mainsail, then there would be some limited fore and aft spreader base movement, but if not, then it does not make much difference, and so best to play it safe and fix the base.

    That seems to be the conclusion. I just needed to confirm my own thoughts, so thanks guys.
     
  8. CT 249
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    CT 249 Senior Member

    Spreader bases for fractional yacht rigs are often designed with a "web" that provides extra support for the base to prevents the spreaders "scissoring" the mast. On my 28'er the web is a piece of stainless maybe 6mm thick which runs from the spreader base on one side, around the front to the spreader base on the other. I can't recall how far it projects forwards.
     
  9. Mr.G
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    Mr.G Junior Member

    "scissoring"

    CT 249 - do these plates stop the mast from reverse mast bend? I will have to go and have a look at more fractional rigs.

    This is for a cruising boat with a mast that will stay in column.
     

  10. michael pierzga
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    michael pierzga Senior Member

    Yup...i tried to do a quick Google picture search but couldnt bring this detail up.

    They also prevent halyards from getting into the spreader root and prevent chafe.

    Try google again .......
     
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