balanced lug Questions

Discussion in 'Sailboats' started by minno, Oct 29, 2016.

  1. minno
    Joined: Aug 2014
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    Location: Canada

    minno Junior Member

    Hi All

    I'm looking at putting a ~60 Sq Ft balanced lug on my dingy and had a few questions, well, a bunch of questions.

    The dingy is a 10' row/sail with outriggers at about 60" apart at the waterline.

    the sail design I'm looking at

    Foot: 108"
    Luff: 57.5"
    Head: 96"
    Leech: 137"
    Diagonal, clew to throat: 113"
    Square footage (exact): 58.47sqf

    that page doesn't cover shaping the sail so I figured I'd use this page to figure out the rounding of luff, foot, and head as well as hollow for the leach

    I plan on a 12 foot mast and I'd like to make the mast and spars hollow/square

    I thought I'd make the mast out of spruce, 2 1/2" Sq. X 12' long using 1/2 thick strips, the lower ~6' would be solid with a birdsmouth where the hollow section starts.

    will that be heavy enough?

    I've no idea how heavy to make the spars, or if making them hollow will save me any weight.

    would there be any point in making the spars rectangular instead of square? it seems like that would give more resistance to sagging at the ends for the same amount of wood.

    Any links to good info on lugsails would be much apprieciated.

  2. garydierking
    Joined: Sep 2004
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    Location: New Zealand

    garydierking Senior Member

  3. gggGuest
    Joined: Feb 2005
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    Location: UK

    gggGuest ...

    The biggest argument against rectangular spars on a recreational boat, to my mind, is that the corners are so vulnerable to damage. A round spar is much more bump resistant. There are loads of other advantages to be sure, but I reckon that one is the decider.

  4. minno
    Joined: Aug 2014
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    Location: Canada

    minno Junior Member

    Thanks :)

    after looking at that calculator Gary linked to I decided the overall weight of spars + heavy mast is more than I want to handle.

    I know I'd allot rather be cracked in side of the head by a round spar then the corner of a square one given a choice :)

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