pedal powered kayak idea.

Discussion in 'Boat Design' started by WPFix, Jan 30, 2013.

  1. WPFix
    Joined: Aug 2012
    Posts: 13
    Likes: 1, Points: 0, Legacy Rep: 13
    Location: Buffalo NY

    WPFix Junior Member

    I bought my fiance a sit in kayak about 2a years ago. However due to a shoulder injury paddling any further than short distances becomes painful for her. I have been doing some reading on pedal powered boats, but they are all of sit on top design, so their drive systems are of limited help in my endevor to make a pedal powered sit in boat.

    So I had the idea of using a flexible cable drive, similar to the speedometer cable in your car (non-electronic), but more heavy duty. There is a company that makes them called Elliot Industries or something like that. My goal is to use one of these cables from the pedal gear and chain setup, route it out of the boat above the waterline (less chance of leaks), to a prop mounted on the back below the waterline. Has anyone ever tried this? Trying to keep things as low cost and simple as possible, which is why I don't go with something more expensive. Not looking to break any speed records, just for her to be able to keep up with the kayak "pack".
     
  2. Eric Sponberg
    Joined: Dec 2001
    Posts: 2,002
    Likes: 205, Points: 73, Legacy Rep: 2917
    Location: On board Corroboree

    Eric Sponberg Senior Member

    There have been a number of long threads on this forum on "pedal powered boat" and the like, such as:

    http://www.boatdesign.net/forums/boat-design/pedal-powered-boats-23345.html

    http://www.boatdesign.net/forums/props/propellor-pedal-powered-catamaran-21911.html

    http://www.boatdesign.net/forums/boat-design/where-start-pedal-powered-boat-23665.html

    http://www.boatdesign.net/forums/props/pedal-powered-prop-design-34585.html

    http://www.boatdesign.net/forums/boat-design/pedal-boat-propeller-specifications-data-31674.html

    And these are just a few. If you do a search on "pedal powered boat" on this forum, you'll see all these links and a lot more.

    I have not read them all or followed, them, but one thing I think you will find is that pedal powered propellers are very slow turning, and that means they don't produce a whole lot of power. The slower turning a prop, the bigger diameter it has to be. And the bigger the diameter it is, the harder it is to pedal because of the blade drag. But study the threads and see where it leads.

    Eric
     
  3. portacruise
    Joined: Jun 2009
    Posts: 1,052
    Likes: 20, Points: 38, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    WP:

    Begging, borrowing or renting a 2 person kayak might be a simpler solution. Your fiancee could be a passenger, and because of the increased length you might be able to keep up with the pack until her shoulder heals.

    Pedal boat props need a way to remove debris that tangles in the prop periodically, as well as being able to avoid hitting the bottom/obstructions.... The cable system you are considering would require that you get in/out periodically for prop inspection. Unless you are doing completely clear, deep water???

    Hope this helps.

    Porta

     
  4. Submarine Tom

    Submarine Tom Previous Member

    I couldn't agree more.

    Get a two seater.

    Give her a paddle and have her paddle lightly until the first sign of pain.

    Stop, ice, rest and resume.

    It's the road to recovery.
     
  5. Gib Etheridge
    Joined: Nov 2012
    Posts: 28
    Likes: 1, Points: 0, Legacy Rep: 13
    Location: BC Canada

    Gib Etheridge Junior Member

  6. Eric Sponberg
    Joined: Dec 2001
    Posts: 2,002
    Likes: 205, Points: 73, Legacy Rep: 2917
    Location: On board Corroboree

    Eric Sponberg Senior Member

    There you go! System's designed. Pretty clever!

    Eric
     
  7. Gib Etheridge
    Joined: Nov 2012
    Posts: 28
    Likes: 1, Points: 0, Legacy Rep: 13
    Location: BC Canada

    Gib Etheridge Junior Member

    I know there's no such thing at the RPMs that a human can produce, but the prop appears to be weedless.
     
  8. WPFix
    Joined: Aug 2012
    Posts: 13
    Likes: 1, Points: 0, Legacy Rep: 13
    Location: Buffalo NY

    WPFix Junior Member

    Hmm. Thanks for the link. Thats alot like what I am looking to build, but I am looking to build on the cheap. (E-4 pay). Pretty much using garage sale bike parts, but teying to find out where I could get a cable similar to that one. The overall design will be simple, and anything in the 4-5 kt range would be concidered a success.
     
  9. rwatson
    Joined: Aug 2007
    Posts: 5,811
    Likes: 269, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    Last edited: Jan 31, 2013

  10. messabout
    Joined: Jan 2006
    Posts: 2,950
    Likes: 177, Points: 63, Legacy Rep: 1279
    Location: Lakeland Fl USA

    messabout Senior Member

    Rwatson that spidery looking, clamp on, canoe paddling, gizmo is clever as hell. He is using a simple parallelogram linkage to make the paddles work. No chains, gears, propellers or other complications. Because the paddles lift clear of the water at each stroke, they might even clear the flotsom that they have encountered. His pedals are coupled but if uncoupled they could affect steering.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.