Carbon bow sprits.

Discussion in 'Boatbuilding' started by New builder, Jul 21, 2015.

  1. New builder
    Joined: Jul 2015
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    Location: Ontario

    New builder Junior Member

    I'm toying with the idea of building a one off sportboat. 20 to 25 feet. Right now I'm looking at just putting together all the info on items I may need.

    Carbon bow sprits.

    I see many Carbon tube manufacturers online.

    What would be needed in a Carbon tube.
    I'm wondering about the following. Cloth orientation, wall thickness. Inside diameter. Outside diameter. Etc.

    Thanks in advance.
  2. New builder
    Joined: Jul 2015
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    Location: Ontario

    New builder Junior Member

    Lots of views here. Does anyone have any info ?
  3. markstrimaran
    Joined: Dec 2014
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    Location: usa

    markstrimaran Senior Member

    carbon fiber bow spirit

    It depends on the length. You said it's for a sportboat. I am not sure what it needs to hold up.
    My spirit pole is 3 feet long. 1.5 inch .055 thick steel cored with spruce dowel rod epoxied inside. It is suitable for a 26x14 Genoa in a 20 mph wind.
    A 3 foot carbon fiber pole of 2.5 od 1/8" walled would be more than than sufficient on a small sail boat. .045 Thinner walls are OK depending on who is laying it up.
    An old wind surfing mast. Might be a place to start. I am not a huge fan of ultra light weight composites that can fail catisrophicly.
    The most critical point will be were it mounts too the bow.
  4. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    It's ludicrous to suggest any spar specification(s) without having an idea of the loads involved. Simply put, the plans will contain and laminate schedule and this should be adhered to closely. If you want to change fabrics or materials, then you need to run the numbers for each element and work up the new laminate schedule or material specs, based on the substitute material physical attributes. There is no short cut around this, particularly with composites, unless you're just building way heavier than you really need, in which case, just make it overly stout and take the weight penalty hit.

  5. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    Once you know the specs, you can make your own sprit using a plug made from (tapered) Styrofoam. You laminate the carbon fiber over the plug and then melt out the foam using acetone. A friend used this method to build a sprit for a 40 ft Chris White Skyhook trimaran.
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