Advice on a boat i saw in Alexandria

Discussion in 'Powerboats' started by Vulkyn, Nov 3, 2013.

  1. rxcomposite
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    rxcomposite Senior Member

    PAR,
    The pictures I have posted refers to scantling arrangement of the “traditional” or “ancient built” boats particularly, the mating of discontinous highly curved frames and stiffener to the exposed keel. One look at the pictures posted by Vulkyn showed it is traditional boatbuilding.

    Traditional boat construction is very much alive in the Middle East and part of my stint over there covered the restoration, repliclation, outfitting, drydocking/repairs, and documentation of scantling arrangements of several ancient built boats (60 to 100 years old, 12 to 80 footer).

    Another good book, “Details of Classic Boat construction” (author unknown, part of research material) deals with wooden boat construction but does not deal with keel to frame details. Half of this book is a copy (part of) of the 1981-82 edition of LR rules on Wood and Composite boatbuilding, a slightly modern approach to wooden boat design.

    Picture number 1 in your post is a modern method of construction. In fact the scantling arrangement is the one that was used in the design of a modern FRP patrol boat. That is, two deep internal longitudinal running the length of the boat supporting the transverses.

    I think the confusion lies in the terminology and the design method. I opened the section on “floors” in the 1982 LR edition and the result is as posted. In the modern edition of Class Rules, I open “floors” in DNV (FRP construction) and it generally refers to the span of the floor (sole) supported by a central girder or longitudinal. I think LR speaks also of the same.
     
  2. PAR
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    PAR Yacht Designer/Builder

    I understand where you're going, but this isn't what the pictures show. The pictures show plywood planking, hard fastened to the frames and each other (laps) with screws and though I can't truly see it, I'm betting also over polysulfide or polyurethane (lets hope it polysulfide). It's tough to judge the planking thickness, but the frames are quite heavy and fairly closely spaced (not overly so), suggesting a modern approach. In fact, I would think they could have saved some weight in those frames, had they been daintier and on closer centers.

    Admittedly, without a look at the plans, to see what has been done and what needs to be done, makes much of this speculation. In fact, the best advice on this boat is to not consider purchase, without a full set of plans and a very detailed report on what has been done and more importantly, what hasn't.
     
  3. rxcomposite
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    rxcomposite Senior Member

    The ring frames are laminated it seems by the plugged holes I see on the sides. I agree it seems overly thick but must be to compensate for a weak glue that was used, too many joints, or weak lumber.

    The modern boat that I know of built with laminated wood is the Tenacious, a sailing ship for crews with mixed abilities (http://www.westsystem.com/ss/tenacious-a-look-back/). The design philosopy is that the wood is laminated horizontally and pegged vertically because the shear of the peg is greater than the shear of the glue.

    I know it was built to LR standard and the construction method was outlined in a coffetable book. Interesting method of construction and it is to Class standard.
     
  4. TeddyDiver
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    TeddyDiver Gollywobbler

    Displacement-40hp.Semiplanning-150hp(wildquessIfItMakesIT)
    SorryThisLaptopDoesntHaweAllKEysWorking:D
    RegardsTeddy
     
  5. Vulkyn
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    Vulkyn Senior Member

    40 HP ? for that monster ? is that not severely underpowered ?
    (Its ok Teddy i can read with out spaces ..... :p )

    No such thing as full set of plans in Egypt, unfortunately the builder who built this boat is probably one of the best you can get in Egypt. Most builds don't even balance out when they are put at sea ....

    I will pay them a visit however i would need to cover as many inquiries as possible from our experts.
     
  6. TeddyDiver
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    TeddyDiver Gollywobbler

    DependsSomeOfTheDisplacemen.40hpIsEnoughTo7.5KnotsFor35'5tons.ThouIt'sFullThrottleThen.AndOfCourseWithOptimalPropeller.
     
  7. hoytedow
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    hoytedow Wood Butcher

    It is not a planing hull definitely displacement so you won't need that bigger engine. A 50 hp diesel would probably serve you well with a lower pitch propeller. [​IMG]http://www.boatdesign.net/forums/attachments/powerboats/86059d1383511425-advice-boat-i-saw-alexandria-87150023.jpeg
     
  8. PAR
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    PAR Yacht Designer/Builder

    Without plans, regardless of who built it, you will be forced to continue using his work, which seems to be to be less then ingenuous. Considering the price, you should walk away, unless the equipment that comes with it can justify the cost. There's just way too much to have to figure out.
     
  9. michael pierzga
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    michael pierzga Senior Member

    Plywood ?

    I dont see any plywood in the hull .
     
  10. PAR
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    PAR Yacht Designer/Builder

  11. rxcomposite
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    rxcomposite Senior Member

    This is the 44 foot boat built by the local craftsman in which I was the project coordinator. It is a replica, built in the traditional way. Notice the alternating frame spacings. The way the frame is attached to the keel is exactly as pictured in the drawing I posted. Keel, garboard, keelson, bolt, floor. Bulletproof.:cool:

    Most of the traditional boat's hull looked the same. It is above water that makes a difference and only the experts can tell the type of boats. Attached photo shows several sizes. 3rd picture is a small one and the 4th is a model.
     

    Attached Files:

  12. michael pierzga
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    michael pierzga Senior Member

    Looks like timber to me. Marine ply is very hard to buy in that part of the world.


    http://[​IMG] sube
     
  13. michael pierzga
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    michael pierzga Senior Member

    As for power. Obviously a small diesel.

    Best to ask the man who built it for thoughts on power.

    That is a low power hull so 50 hp of whatever size the locals use.
     
  14. PAR
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    PAR Yacht Designer/Builder

    I wouldn't touch it, personally. You're right the topside planks look solid, but those bottom planks sure look like plywood.
     

  15. SamSam
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    SamSam Senior Member

    .

    Those are plywood planks.

    At the top of the picture, the seams are cracking. Is that normal? What ultimately seals the laps?

    [​IMG]
     
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