Box Mast Fears

Discussion in 'Sailboats' started by Prtndr37, Jan 21, 2009.

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

    PAR Yacht Designer/Builder

    Ferro cement is a reasonably accepted building material in some parts of the world, but in the USA, it has a pretty bad reputation. There are a few valid and a few not so valid reasons for this, which you likely know already.

    In the USA, it will have the lowest resale value of all the building materials and is the most difficult to survey accurately or completely.

    If the boat was built by Windship Limited, then your value goes up a touch, if the buyer is aware of the quality of their hulls, but other wise, it's white elephant that's very difficult to sell. The same is true of Jay Benford designs, built to his plans.
  2. MikeJohns
    Joined: Aug 2004
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    Location: Australia

    MikeJohns Senior Member

    Internal halliards aren't a good idea, better to keep the mast weathertight. Internal wiring is commonly installed.

    Tang fasteners are usually bolted with a compression tube right through the mast and internal block, the question of the internal blocking causing a stress raiser really depends on the wall thickness relative to the section size. A thick wall and I don't think its going to be an issue. But simple to Cut an intersecting V shape in both directions (fore-n-aft and side to side) in the blocking. I used to see very large masts made like this a few decades ago, Oregon was the preffered timber here.
    Wooden masts can be very durable and strong, surprisingly so if you can source the timber.
  3. Prtndr37
    Joined: Jan 2009
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    Location: Grand Rapids, Mi

    Prtndr37 Junior Member

    No, I'm not to worried about those issues. Just concerned about the structural. It's a little nerve racking contimplating building your own masts.

  4. Prtndr37
    Joined: Jan 2009
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    Location: Grand Rapids, Mi

    Prtndr37 Junior Member

    Since its been mentioned....two sidewalls are 1 5/8", the other are 1 1/4".
  5. Brent Swain
    Joined: Mar 2002
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    Location: British Columbia

    Brent Swain Member

    Three foot by two inch wide strips of inner tube make great gluing clamps. Bicycle inner tubes also work, and most bike shops have a garbage can full of them, free for the taking. Don't put too many on or you will crush the wood.

  6. ancient kayaker
    Joined: Aug 2006
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    Location: Alliston, Ontario, Canada

    ancient kayaker aka Terry Haines

    Build a short section first using cheap materials. You can establish methods, jigs etc that suit you and get a heads up on the problems.
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