Smallest boats

Discussion in 'Boat Design' started by Luis Cunha, Dec 2, 2007.

  1. Luis Cunha
    Joined: Sep 2007
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    Luis Cunha Junior Member

    Hello,

    During last two weeks I habe been thinking about the smallest powered, sailling and paddling boats for one person seated in a very confortable position.
    I have tried to draw something interesting to attached here but unfortunatly no creativity.
    In my opinion, this subject is very interesting, isn't it?
    I would appreciate to know your thoughts about this.
    Thanks in advance for your comments.

    Luis Cunha
     
  2. masalai
    Joined: Oct 2007
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    Location: cruising, Australia

    masalai masalai

    Bath tubs have alreadt been done.
     
  3. Loveofsea
    Joined: Jan 2007
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    Location: Southern California

    Loveofsea New Member

    2 mil wetsuit with jet fins or a kayak|

    seriously!
     
  4. Guest625101138

    Guest625101138 Previous Member

    Luis
    The attached video clip was produced by a fellow OzHPV member. I am on the black boat. The yellow boat is one of my earlier versions. It is also on YouTube but image quality not as good:
    http://www.youtube.com/watch?v=ckWqIgmVM4Y&feature=related

    These boats are a nice way to get around on the water. The black one is a bit extreme for car topping because of length but is light and easy to handle. It also travels well on the car because it has little frontal and side windage.

    It is not physically pressing to cover 100km a day in sheltered water in a boat like this. A healthy adult should sustain 10kph with a well designed light boat. You can do about 8kph with the same effort as a brisk walk. 10kph takes about the same effort as 10kph jog on undulating land. You can eat and drink while in motion.

    I can be on the water in the fraction of the time of a sailing boat. On an all-point course I can go faster than sailing cats of 14ft or smaller even in strong wind. They cover much more distance but they only do better distance made good in time on a reach. I kill them upwind and I normally do better downwind.

    It is a good way to stay fit. You have really good control over the boat. It is very responsive to pedal effort and steering commands. I am on the experienced side of 55yo and can push the boat over 18kph for a few seconds. There is little skill involved unlike the ballance and technique of rowing or paddling. You do develop muscle coordination over time to improve pedalling efficiency.

    One issue is sunburnt legs and arms but I have full length "Skins" that I use for extended periods on the boat.

    There are a number of commercial designs. Cadence is the Rolls Royce but a bit heavy. Hobie Mirage are OK for up to about 8kph - robust and simple. Nauticraft make nice boats, roomy but slow. WaveWalker is the new kid on the block - probably better than Hobie but performance still limited by its length.

    I have another version that provides more protection but it is a bit heavy for car topping. It also has a swing arm pedal action that most find more natural than cycling:
    http://www.youtube.com/watch?v=PYoW3XjHRbw

    Rick W.
     

    Attached Files:

  5. Luis Cunha
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    Luis Cunha Junior Member

    Hello Rick,

    Many thanks for your reply. Your cooperation is always very appreciated.
    I think that the length of your boat is around 2 meter and wide 0.5 m.
    I would like to find more compact boat for a person even if necessary with technology to get stability. The ideia is select or develop the smallest salling, paddling, cycling and powered boats. Mini boats can be a good commercial idea.
     
  6. ted655
    Joined: May 2003
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    ted655 Senior Member

    There is also a bicycle centered on pontoons. Chain drives a propeller, handle bars are adapted to a rudder.
    Also a 3 wheel tricycle on BIG plastic balloon wheels. Great fun (until the wind blows)
     
  7. Ike
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    Ike Senior Member

  8. kengrome
    Joined: Jul 2006
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    kengrome Senior Member

    Hi Luis,

    I have a design for a small 3 piece take-apart boat. Its original concept was to be a small one-person motor boat for protected waters. The engine is a 25 cc grass trimmer engine installed inside the aft module. The aft and forward modules can be detached from the center module and fit inside the center module for transport and storage. The entire boat ships and stores inside its own 1.5' by 3.0' by 4.0' plywood crate/box.

    I considered a pedal drive unit in the same boat but decided to offer a different model for this propulsion system instead. I never considered sails because of the boat's intended use and storage and the complication of long mast, daggerboard, etc. not fitting into the same size box.

    No matter what the primary propulsion might be, oars or a paddle would be a recommended backup.
     
  9. Guest625101138

    Guest625101138 Previous Member

    Luis
    The main hull on the black boat is 7.4m long and 220mm wide. Short disploacement boats are slow. If it is intended for athletic people you could use hydrofoils on a short catamaran. The physics condemn short boats to be slow unless you have the power to fly.

    Rick W.
     
  10. Luis Cunha
    Joined: Sep 2007
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    Luis Cunha Junior Member

    Kengrome,


    I'm very interested to see a photo of your small 3 piece take-apart boat.
    It seems be a great idea.
    Waiting your reply.

    Ike,

    Thank for you information. I'm going to envolve on this group.


    Rick,

    Thanks again.
     
  11. kengrome
    Joined: Jul 2006
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    kengrome Senior Member

    These are preliminary, the concept is not complete by any means, but this will give you an idea of where I'm headed:


    [​IMG]


    [​IMG]


    The transverse line across the forward deck shows the location of the forward bulkheads where the bow section will attach to the mid-section. The aft section attaches at the backrest / bulkhead. Both the forward and aft sections fit inside the mid-section for transport and storage. Waterline is 4 inches at 250 pounds displacement.
     
  12. Luis Cunha
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    Luis Cunha Junior Member

    Dear Ken Grome,

    I think your idea is not complex which is very good and is interesting too. Congratulations and thanks to share with us.
    Can you tell the size of the assembled and disassembled boat
    Waiting your reply
     
  13. kengrome
    Joined: Jul 2006
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    kengrome Senior Member

    Hi Luis,

    The full size is 7.0' long by 2.9' wide by 1.3' tall. When disassembled it will fit into a 4.0 by 3.0'' by 1.5' plywood box for shipping and storage. This is clearly a special purpose boat for one person to use in protected waters. My goal is to have this boat "fill the gap" in the market for a small power boat, assuming there is such a gap ... ?

    There may be people who cannot (or do not want to) rely on their own muscle power to do the type of fishing or exploring they wish to do -- fishermen who must travel a long distance over water from their launch point to their fishing grounds for example, or explorers who want to extend their explorations beyond their paddling limits. These people might appreciate a small motorboat that will get them to their destinations via engine power, thus saving their muscles for use with paddles or oars "when they get there".

    Yes I recognize that I could use a battery powered electric motor, but a small gas engine and a couple liters of fuel are much lighter and will give the boat much greater range ... and more gas can be purchased elsewhere if needed. Don't get me wrong, I like the quiet of electric motors, but they have limitations which make them impractical in this application which is why I plan to use a small gas engine in this boat.

    Although I wanted a very stable boat a fisherman can stand up in, the primary goal of this boat was to design it to take apart and "fit inside itself" to make shipping and storage more reasonable. It's the kind of boat an apartment dweller might love since its shipping crate can do double-duty as furniture. Just cover the boat's shipping crate with a nice cloth or have a seamstress sew a custom fabric cover for it, and no one will ever know that the box your TV sits on in your living room is also the storage container for your own little take-apart power boat ... :)
     
  14. rwatson
    Joined: Aug 2007
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    rwatson Senior Member

    No - one in this thread has mentioned www.streamdancer.com
    There is a discussion on this design under "New design gets attention"
    I think this concept has filled this niche "in spades"
    Got a wheel for pulling to the water, super comfortable seat, electric trolling motors, stable - the whole enchilada
    Small 4 stroke engine would complete the set!
     

  15. kengrome
    Joined: Jul 2006
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    Location: Gulf Coast USA

    kengrome Senior Member

    Hi Ray,

    StreamDancer will certainly be a great little boat when it goes into production, assuming it works as shown in the movies, there's no doubt about it! But no one knows the price yet, and it will certainly be expensive given the cost of molds for roto-molding, the high-tech electronics controls, and the other custom parts required for such a boat.

    My little take-apart boat targets a very different market. Mine is intentionally simple, affordable and "low-tech" because I want people to be able to build it themselves, assuming I produce plans or kits some day. My boat focuses on the long range water traveler too, rather than the guy who can drop his boat into the water close to his fishing grounds. If you don't have to go far from your launch point electrics are fine, but when you want to go long distances little gas engines make a whole lot more sense, and they do not carry the weight penalty of several lead-acid batteries.

    The StreamDancer doesn't come apart and store in a small box either, nor can it be taken to the launch point in the back seat of a compact car. I also suspect that it will will weigh substantially more than mine when the complete power system is included, although the weight of either boat is not a concern when they both can be carried in pieces.

    All in all I think the StreamDancer is going to be a very popular boat if the price is low enough to make it attractive. There is something inherently "fun" about being able to control the boat with your feet while using your hands to cast a line or eat lunch or take photos. That's why I'm glad my little boat is targeted to meet the needs of a different customer -- a person who wants a boat to go as far as he likes without worrying about draining the batteries, or a person who prefers a boat that stores in half the space, or maybe just a person who prefers a boat he can build himself for a fraction of the cost.
     
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