Gougeon type spar for Spray 27?

Discussion in 'Sailboats' started by sjo hest, Feb 16, 2007.

  1. sjo hest
    Joined: Jan 2007
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    Location: Montana

    sjo hest Junior Member

    Has anyone on the forum built a strip composite mast or spar as outlined by the Gougeon brothers? (My book is the '89 edition labeled "New Revised Edition," and the method is outlined on page 181.) Basically one builds a half section of the spar over forms just as one would a stripper canoe, then builds a second, fiberglassing each inside and out, finally joining the two. To anyone who has built stripper canoes the method seems somewhat simpler than building a bird's mouth spar.
     
  2. fhrussell
    Joined: Dec 2004
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    fhrussell Boatbuilder

    You may want to ask this in the 'multihulls' section..... Probably a few people there can answer your question.
     
  3. messabout
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    messabout Senior Member

    Birds mouth is easier, surely quicker, than strip building. No form is required, there are only eight pieces to deal with, In two or three days you can have a birds mouth spar. It'll probably take that long to build a suitable mold for the strip built spar. Agreed, the strip built variant is more elegant.
     
  4. sjo hest
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    sjo hest Junior Member

    Thanks, Messabout, and you're probably right, though the form shown by the G. bros is relatively simple--half-circle sections of plywood, slightly descending in size if you want a taper, secured vertically on a straight surface (I have a long, solid flat-bed trailer that would work). I've built strip-planked canoes, so the method attracted. If there's any advantage over birdsmouth I'd think it might be that one could take his time--no frantic time crunch once the epoxy is applied to the birdsmouth sections and the circular clamping takes place. But I can see the truth in what you say--birdsmouth is probably considerably faster. Thanks, Dan
     

  5. messabout
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    messabout Senior Member

    From a purist point of view the G brothers method is the best of the two options. Purist: The birdsmouth does not produce a structure whose elements are all the same thickness. After building the octagonal assembly most people will plane it to a round shape. The birdsmout advantage of a lot of glue surface is partially diminished when some of it is planed off. (quickly dulling your expertly sharpened plane iron) After the planing job the middle of the segments are thicker than the part nearest the glue joint. Probably does not matter but it gives us something to argue about. The BM method require that the 90 degree groove be perfect or the parts will not "fall together" as some claim. With the right router or shaper, slot perfection is possible. Try to do it on a table saw and grief is in the offing.

    With the strip built method you can build the spar in any shape you want. You can also build a luff rope slot in if you choose. I'd want to use bead and cove strips to make the job easier. All things considered, I think I might build my next mast with strips.
     
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