How To Scribe A Waterline

Discussion in 'Wooden Boat Building and Restoration' started by abckits, May 27, 2008.

  1. abckits
    Joined: Aug 2006
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    Location: LUNENBURG NS

    abckits KILLICK

    This Is A 24ft. Wooden Sailboat On Dry Land.
    Not Level. Need Info On How To Find And Scribe New Waterline Since Engine Change.
     
  2. longliner45
    Joined: Dec 2005
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    Location: Ohio

    longliner45 Senior Member

    not beeing a smart ars,,my prints are accurate,,,but for kicks and grins ill be putting a fatter bootstrip on her,,longliner
     
  3. Landlubber
    Joined: Jun 2007
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    Location: Brisbane

    Landlubber Senior Member

    abckits,

    The easiest way to scribe a waterline is to level the boat (just use jacks), then with a 1/2" clear plastic tube fill it with water, put one ond to the bow, mark the water level in the plastic tube with a marker pen, and then have someone walk around the boat marking the waterline all the way.
    Check the bow and stern first to make sure that the correct line is true. You need to know of course where the waterline should be at the bow and stern before doing this. Also it has to be level athwartships too of course.

    Now if you have added a different engine, thus altering the old waterline, then the game is quite different. If there is a radical weight difference, then the load waterline will be different of course. This can only be worked out by knowing the TPC imersion of the waterline involved, finding the new Cof G and doing the calculations.

    Which of these two is your requirement?
     
  4. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I've found it's a lot easier to use a laser then a water level and there is no real way of determining the LWL without it (the boat) being leveled (in both directions). If many changes have been made, you'd be best advised to splash the boat, wait a month, mark the LWL with primer or scratching, haul it then paint the proper line.
     
  5. Landlubber
    Joined: Jun 2007
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    Location: Brisbane

    Landlubber Senior Member

    Yep, can only agree. Very sensible and practical if possible.
    We do it often in the trade.
     

  6. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    If the boat is old enough, the line's been scribed and painted over and the paint has filled the scribe line. If you or someone else haven't sanded it out, there would be enough of the line left to rescribe it.
    If you make marks, one every three feet, for example, where you think the waterline should be, and drip some Zip Strip over the marks, then wait and wipe off (might take a few applications), you should reveal the old marks enough to connect them with a batten.
     
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