New power cat - help please!

Discussion in 'Powerboats' started by foxfish, Aug 2, 2008.

  1. Jimboat
    Joined: Feb 2002
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    Location: Canada

    Jimboat Senior Member

    foxfish - thanks for PM. i really can't analyze performance without more info on proposed design, weights, etc. I'm sure that you'll have plenty of fun building and testing and modifying your boat. Let me know if i can help.
     
  2. foxfish
    Joined: Jun 2008
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    Location: guernsey

    foxfish Junior Member

    The pic shows half the transom on a hardboard template, I think the hull angle is 17 degrees, what would be the effect if I changed the angle to say 14 degrees?
    This would give me more buoyancy but what is the trade off?
    (650 = total height)
     

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  3. Jimboat
    Joined: Feb 2002
    Posts: 236
    Likes: 10, Points: 18, Legacy Rep: 130
    Location: Canada

    Jimboat Senior Member

  4. f250
    Joined: Feb 2009
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    Location: belgium

    f250 Junior Member

    evolution

    any evolution?
     
  5. foxfish
    Joined: Jun 2008
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    Location: guernsey

    foxfish Junior Member

    Yes some, I have been doing a lot of sanding with the 9'' grinder, in fact the the boat must be half of its the original weight!
    Of course I will be replacing all the material with fresh glass but at the moment its just more sanding!
     

  6. Ernie Travers
    Joined: Feb 2009
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    Location: Auckland, New Zealand

    Ernie Travers Junior Member

    Hello foxfish,
    we built about 23 power catamarans from 8.2m to 13m under the brand Silver Tiger. Each one was a development of the previous boat. The most efficient was 9.75 loa with a flybridge. With two 250hp outboards it used 1L petrol/motor/NM at 20 knots
    The same fuel consumption at 35knots that our previous cats got at 25knots.
    3.5L/NM/motor at it's top speed of 48 knots.
    With 50hp motors on a 5m boat, you need a planing bottom.
    One of our cats was hit by a heavy boat on it's mooring and went ashore on rocks in a 100knot storm. My son pushed it off the next day in a 50knot wind and drove it for an hour and onto a boat ramp.
    We were considering selling plans and have CAD sketches of rather stylish 6m and 7m boats. We could easly draw a 5m if you are interested.
    If you supply your e-mail address, I will send some photos of some of the cats and the rescue off the rocks.
     
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