Runners

Discussion in 'Sailboats' started by skatun, Apr 24, 2015.

  1. skatun
    Joined: Sep 2010
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    Location: Aachen

    skatun Junior Member

    Hi, we are renovating/rebuild an old boat Rainbow42.

    However since we are only 2 people, we were wondering if we could get rid of the runner and only have the backstay. We are just cruiser and do not worry to much about the mast trim. By doing this the boat will be easier to tack, make wider in the back, fit a bimini, solar panel etc.
     
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Runners are usually used in fractional rigs with very thin section masts. They prevent the mast from buckling and breaking. You may install a set of lower shrouds instead. The higher angle will make them less efficient, but if you are not pushing the boat as hard, they may be sufficient.
     
  3. TANSL
    Joined: Sep 2011
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    Location: Spain

    TANSL Senior Member

    Runners are used in fractional rigs to control mast bend.
    The runners have the same function as the back-stay on a masthead rig. Forestay sag will decrease and the mast will bend to flatten the main, when you tighten the runner. The permanent backstay on such a fractional rig is primarly an insuranca against rig failure when gybing. (text from internet)
    Nothing about mast compression. Breaking a mast for buckling is not easy to get, breaking it for bending is possible.
     

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    Last edited: Apr 24, 2015
  4. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Tightening a runner increases the curvature on the mainsail (more draft). Runners are really important when going downwind. On light to moderate wind, the runners are usually left unused and attached to the shrouds. The fractional rig II seems like a possible option. However, the shroud attachment will likely have to be moved aft. There will have to be some structural modifications to get the chainplates in the new location. Changing to a masthead or 7/8 rig could also simplify your problem.
     

  5. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    You could use a fixed backstay on that boat, though a great deal of adjustment will be lost and you'll probably need some jumpers to transfer the headstay loads. Since you're a cruiser, some sort of B&R rig might be doable, though I'd be inclined to recommend the standard double lowers and cap setup, because you're just a cruiser. The double lowers arrangement will hold the stick and introduce some pre-load, while the cap keeps things in column. A split backstay would be the cruiser option and though you lose some adjustment, at least the stick is well supported.

    Of course, as has been noted by others, the attachments on the stick and deck will need to be relocated, which requires localized reinforcements in these areas. These can often be in difficult to access areas and costly.
     
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