pedaled powerd prop fishing boat?

Discussion in 'Projects & Proposals' started by creekhound, Nov 19, 2009.

  1. Guest625101138

    Guest625101138 Previous Member

    The idea with a twisted chain drive is to have them tilt up so you can beach the boat. You can do this easily between the hulls with a cat or with a well in a single hull.
    http://microship.com/bobstuart/spinfin.html
    http://www.recumbents.com/WISIL/hpb/compact_drive.htm
    http://microship.com/bobstuart/lambordinghy.html

    When operating you will need about 18" of water unless you use something like my curved shaft. This can be lifted up and operated partially submerged. I can operate in about 6" of water over sandbars and through weed.

    Rick W
     
  2. creekhound
    Joined: Nov 2009
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    Location: aurora,Indiana

    creekhound Help me !!!!

    Well i would need a system like yours for the shallows.is there a smaller prop i can use and just up gear ratio git to about 12 inchs max draft?Also some of these new rubber belts are pretty awsome and are used as twist belts on machines at work.I see now reason they couldnt be used for this and they are much more natural to twist than a chain.What do you think?Also i am drawing up scetchs of a mono cat hybred so i can access the prop i have located 8mm spring steel and waiting on price.I just dont want to git wet all the time in the wake of boats iwould sit in mano hull with to cats coming off back does this make any sense to you. Again thank you you have been so helpfull
     
  3. Guest625101138

    Guest625101138 Previous Member

    The narrower toothed belts are quite good for twisting. Attached shows the belt used on the Nauticraft:
    http://nauticraft.com/?page=encoregallery
    I have used wider belts in straight line system. I find they are quite expensive compared with chains.

    You can use smaller props if you spin them faster but the efficiency drops away. You could use something around 8" and get acceptable performance. It would need to be more like a typical marine propeller because a model plane prop of this size would not have the blade strength to handle the thrust:
    http://www.mcmaster.com/#propellers/=4muo17
    These are quite expensive unless you find something on Ebay.

    The idea of a monohull with stabilisers works well

    Rick W
     
  4. creekhound
    Joined: Nov 2009
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    Location: aurora,Indiana

    creekhound Help me !!!!

    not really stabilizers i dont know how to explain it other than two forks off the back of the boat one on each side with the void in the middle so i could access the prop.Also how much faster would it have to spin 20 to 1 ?
     
  5. creekhound
    Joined: Nov 2009
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    Location: aurora,Indiana

    creekhound Help me !!!!

    wow those props are expensive!!! Hmm what to do about a prop.cant really turn a trolling motor prop fast enough what about making one where would i git specs? thanks agian you are a life saver i hope i am not bothering you.
     
  6. Guest625101138

    Guest625101138 Previous Member

    You could expect to do about 8ft/s. So a prop with a 12" pitch will need to spin about 8 times your crank speed.

    If you can weld and have a hand grinder you can make a prop in a few hours from 1.75" by 1/8" flat bar.

    I have a procedure for making a prop like this that others have used.

    Your idea for a tunnel is OK but it needs to blend well with the front of the hull otherwise you will have horrendous drag.

    If you are likely to operate in any weed you need a prop that you can get to by hand. Any weed on the prop will drive you nuts. It is like riding a bike with a brake applied.

    Rick W
     
  7. creekhound
    Joined: Nov 2009
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    Location: aurora,Indiana

    creekhound Help me !!!!

    so a 10 to 1 gearing would be enough.and machining is no problem i work in a major shop we work on local transit buses.i can weld and have access to have machining done for free.this might be a dumb ? but how much flex can you git out of a spring steel rod.I will try to git my scetchings on here for you to see if you want. mostly mods on others plans i just dont want to git wet in a cat some of my fishing is in cold weather can a small cat be inclosed?
     
  8. Guest625101138

    Guest625101138 Previous Member

    If you want to get into detail on a design then it will be better to email direct:
    rickwill@bigpond.net.au

    You will only need a 1/4" spring steel shaft if you spin it at 8 times or more. The bend radius should not be less than 3m. This sounds a lot but you will be able to do that with a 3 to 4ft shaft depending on how you mount the box. Maybe 6ft if it is mounted at deck level.

    Even getting 8X will be difficult with standard bicycle parts. Normal chainrings are 52T teeth. Larger ones get expensive - over $100. You will not get smaller than 11T on a standard cassette.

    I have done almost 8X using a standard chain ring, 14T sprocket and 1:2 right angle gearbox similar to the one on Ebay that I linked to previously.

    What size round bar have you got for a hub. Something like 1.25" diameter is ideal. If you use mild steel for the prop it will need to be painted well. Stainless is better if you have access to that at the right price. You need some round bar for the hub and flat bar for the blades.

    Rick W
     
  9. creekhound
    Joined: Nov 2009
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    creekhound Help me !!!!

    i ran the number and at 8 ft a sec i would be at almost 5mph give or take.that seams a little fast dont it.how fast do you think the average paddeler travels in a 12 touring kayak?also gitting to the prop would be done through the cat portion of the boat behind my seat if that makes any sense with out pics.
     
  10. creekhound
    Joined: Nov 2009
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    Location: aurora,Indiana

    creekhound Help me !!!!

    metal will be a benifit from my work if you git what i mean.only out of pocket metal would be shaft.and would aluminum be better than stainless for prop and my latest plan involves using a belt and machining aluminum pulleys instead of bike gears still use peddels though.so i can make almost any sive pulleys i want just cost me asking a favor but i have to git this all right the first time cant be asking to many favors!!
     
  11. Guest625101138

    Guest625101138 Previous Member

    I am not far off 60yo (sadly) and can sustain 10kph (6.2mph) for hours on end in my V14 boat - attached shows one of my river runs while on holidays last month. This boat is about as efficient as I can make so I am making allowance for inefficiencies in your design estimating around 8kph (5mph) for the time it will take you to get to your fishing spot.

    A well designed prop driven boat will do quite a lot better than a kayak. Props are considerably more efficient than a paddle and much better than the Hobie flapper drive. A friend in Canada did 245km in 24 hours on a copy of my V12 design - so averaged better than 10kph for the entire time.

    Rick W
     

    Attached Files:


  12. creekhound
    Joined: Nov 2009
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    Location: aurora,Indiana

    creekhound Help me !!!!

    My goal is to go no slower than i did in my touring kayak at an average pace since i am average at best of a paddeler.and most fishing would be done in a mile maybe 2
     
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