My Boat is wet!!

Discussion in 'Powerboats' started by Willallison, Feb 3, 2004.

  1. Willallison
    Joined: Oct 2001
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    Location: Australia

    Willallison Senior Member

    No, no - not on the bottom - on the top! :confused:
    Prior to purchasing our Offshore 48, we had admired her hullshape for some time: assuming that the high, flared bow would ensure that she would be a dry boat. However :mad: in just the slightest slop - as little as 6 inches! (and especially in a breeze off the bow) a continuous stream of spray rains down on her.
    It is my theory that the wide (at least 6") flat chines 'smash' the waves, out & away from the boat, whereupon the wind whips it back & prompltly dumps it on the deck :mad:
    Now - to the to fix it?
    My idea is to install a small, angled down lip on the outer edge of the chine - hopefully directing the water back downwards. Any thoughts / suggestions? I'd like to make the installation temporary in the 1st instance - in case I've got it wrong... :eek:

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  2. Tom Lathrop
    Joined: Oct 2002
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    Location: Oriental, NC

    Tom Lathrop Junior Member

    Nice looking boat, Will. :D You made quite a leap from our earlier discussions. A very large trailer and tow truck will be needed! Hah. :p

    When running into a chop with the wind off the bow, there is going to be spray if the boat is moving very fast at all. If it is very fast, the spray will come to rest far aft or behind the boat. If the bow is riding high the spray will also be further aft. Flare helps keep the boat dry but only when going into the wind where the spray will be directed outward. A boat like yours that appears to hold its bow down is normally going to be wet in an off the bow wind. I don't think the chine flats are too much at fault. They may make for more spray and less heavy water as they further break up the water being directed sideways from the hull. So if thewind is up, the lighter spray may get blown back into superstructure more than without the chines. That is the deal with round bottom hulls. Less spray and more green water. I'll take the spray over the heavy water. I expect you know all this. This is about the only condition where my boat, with pronounced chine flats, takes spray.

    Will some sort of chine "deflector help? :?: I don't know, but if it was easy, I expect we would have seen a lot of them around. Some boats do have vertical rails on the chines, C Dory, for instance and there was something called the "wave collector" long ago that was a sharply downturned edge on the chine. Certainly a vertical rail or lip on the chine will contain some of the spray, but there may be other disadvantages that keep them off boats.
  3. Willallison
    Joined: Oct 2001
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    Location: Australia

    Willallison Senior Member

    LOL! :D I wish I could say she she was mine Tom - in actual fact it is my parents boat - I just use it all the time!! ;) (The picture I posted was from a brochure btw - not our actual boat, but a sistership nonetheless) Prior to that "we" owned a 36ft CheoyLee round bottomed displacement cruiser. This boat remained dry until the wavws reached several feet, yet the Offshore 48 is wet in wavelets only a few inches high. You are correct about the type of water that comes aboard - it's spray as opposed to green water - hence my theory about the chines.
    Incidentally, a friend owns a 44' Defever - round hull, displacement boat - I've never seen salt water hit the deck....

  4. Specmar.Aus
    Joined: Jan 2004
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    Location: Queensland Australia

    Specmar.Aus DREDGIE

    Hello Will,

    I have only recently joined in to this forum and have enjoyed it a lot so far.
    Your new launch suffers the same old problem we have all faced over time.
    The moulded corners of the chine are made for easy release from the mould and there fore aren’t quiet the right shape. We have added an alloy section to our Alloy Powerboats that helps a great deal in fixing this problem.
    We have not had any noticeable adverse problems with this section attached.
    Our 6 to 8 metre boat’s have a chine deflector runs the full length of the chine and is1 ½’’40mm long and is turned down at approx 60* deg from horizontal.
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