Would that catamaran ever sail?

Discussion in 'Boat Design' started by john5346, Apr 23, 2013.

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  1. Alex.A
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    Alex.A Senior Member

    Multihulls need a finer bow than that. Much finer.....
     
  2. tomas
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    tomas Senior Member

    If you don't really care about performance and fast/easy construction is more important, then go ahead.

    Based on your responses, I would suggest that you buy two matching canoes that are used and low-cost, then attach them together with a simple deck and add your sail rigging. It will save your time and flow better through the water than what you are proposing.

    Not a great solution but it seems to fit your quick and inexpensive priorities.
     
  3. upchurchmr
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    upchurchmr Senior Member

    John5346,

    It's time for you to just build your design and find out for yourself.
    You are not listening to people who know a lot.

    Have you ever been on a boat?

    You are looking at 30% of the build, and you are going to cripple the boat from the start.

    BTW, what is the deal with blanking out the faces on the rowboats? Are they criminals? Might have been better to show the shape of the hull in a cross-section.

    Try looking at the Cross 18. Old school, but relatively simple to build, simple plywood. Perhaps that will be simple enough for you.
     
  4. messabout
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    messabout Senior Member

    John you have no idea who you are talking to on this thread. One of the finest hydrodynamicists in the world has replied and you have no idea who he is. In addition a professional multihull designer, with plenty of international credentials, has tried to tell you some simple truths. Several other experienced boatmen have also tried to be helpful. If you have your mind made up, as it seems that you have, then why ask questions?

    Just build the travesty that you have drawn and discover your folly first hand.
     
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  5. JRD
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    JRD Senior Member

    John, Did you ever build your rectangular kayak?

    Leo...... Maybe a module for Michlet that analyses rectangular hydrodynamic structures may be a worthwhile upgrade...... :D

    http://www.boatdesign.net/forums/boat-design/case-square-rectangular-kayak-33745.html#post381935
     
  6. NoEyeDeer
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    NoEyeDeer Senior Member

    Ok, I'll bite. No idea why, but what the heck. :D

    John, think about it a bit more. What is difficult about getting two side panels and bending them around a middle frame so they meet at the ends? Answer: nothing. It's really easy. It's easier than what you're proposing, and it will give a better result.

    It will be stronger for the same weight. It will use less material, and therefore be cheaper as well. There will be fewer bits to make. It will look better. It will sail better.

    So, bearing all that in mind, why on earth would you want to mess around with triangles and boxes?


    @JRD: I'm pretty sure Michlet will already tell him that a box will be a pig of a thing for drag. ;)
     
  7. john5346
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    john5346 Junior Member

    Easier.


    That almost sounds like I have to take all knowledge that comes from experts like it is the truth and we all know from the history of science that it doesnt work in a number of cases. It doesnt mean either that any wacky idea that goes against established knowledge is true or that I dont appreciate their help. Only that I take all learning with a bit of questioning.

    Either way, you all agree that:

    - It floats

    - It sails


    If anyone wants to say it sinks or that it wont sail. Then we should discuss again, until then everybody agrees it sails, right?

    Thank you guys :)
     
  8. DennisRB
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    DennisRB Senior Member

    No one said it would not float or sail.

    However, it has been said by experts (and enthusiasts) that:

    It will sail poorly.
    It will waste material compared to a better design so will cost more.
    It will not be as easy to build as you think compared to a much better design.

    The logical conclusion being there is no point to the design.
     
  9. upchurchmr
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    upchurchmr Senior Member

    There have been a lots of you who have tried.
    Its a waste of time.
    I'm going to unsubscribe.
     
  10. Alex.A
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    Alex.A Senior Member

  11. john5346
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    john5346 Junior Member

    Sure it is easy, how can it be easier than that? Looks easier than any curved hull. I agree with you that it wont sail great like a properly design hull but on the building part, it much easier than that. Right? :)

    [​IMG]
     

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  12. Manfred.pech
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    Manfred.pech Senior Member

    Keep it simple

    More than fifty years ago the method of tortured ply has been developed. Nowadays you can use bendable plywood which again is more simple than simple. Take a sheet of ply and cut out a wedge - fold it, fix it, tape it and glass it inside and outside - you have a hull - as long a the sheet (you can get it here up to 25ft or - you make it yourself).

    [​IMG]
     
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  13. troy2000
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    troy2000 Senior Member

    Wrong. I realize I'm just p***ing into the wind here, because you're so bent on rejecting any advice or comments that I wonder why you posted in the first place. But I'll give it a shot anyway....

    How is cutting out, beveling and fastening together the eight pieces of wood you're showing easier than cutting a couple of long pieces, bending them around a center mold, fastening them to a stem at one end and a transom at the other, and slapping a scribed top and bottom on them? The fact that you insist it is proves you're no woodworker.

    Is that solid wood, or plywood? Because if it's plywood you're going to have some serious issues fastening and/or gluing into edge grain, and getting the thing to stay together with no chine logs , stringers or frames. Of course you can do stitch and glue and fillet everything with epoxy, but that kind of blows your whole quick and dirty approach.... If it's solid wood it's going to be expensive and heavy, and you'll still have problems with end-grain fastenings.

    While we're at it, what's your deck going to be made of and how will it be fastened to the hulls? How do you plan to beef up the connections? Not to mention how your mast is attached to the deck...

    Yes, you can build it. You can also crawl to church on your knees, instead of walking -- but why would you want to, unless you're on some weird personal pilgrimage? You'll work harder building the boat your way than you would using the methods and design considerations suggested by others, and it'll sail like a pig.

    I repeat: why do you want to work harder and turn out an ugly and inefficient piece of crap, when it's so easy to do it right and come out with a good boat instead? What point are you trying to make?

    But don't let us stop you; knock yourself out. If you manage to get it built, please post some pictures. We always enjoy looking at other people's projects, whether we agree with the design concepts or not.
     
  14. tomas
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    tomas Senior Member

    Right, but what's the point, why do it?

    I just looked at your earlier Rectangular Kayak thread.

    Again, what's the point, why do it?

    ...and why do you ask all these questions, what's the point?
     

  15. messabout
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    messabout Senior Member

    There are people who derive perverted pleasure by baiting forum members. Descriptive names are; Troll, Poe, Poseur. (see urban dictionary.com) Those people annoy the hell out of us with ploys such as overtly questioning the validity of hundreds of years of firmly established science and thousands of years of boat building discovery.

    We need not endure deliberate controversy while offering sincere and intelligent advice.

    ^^^^^^^^^^^^^^end of rant.
     
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