Pedal Powered Boats

Discussion in 'Boat Design' started by Guest625101138, Jul 14, 2008.

  1. Sockmonkey
    Joined: Dec 2020
    Posts: 27
    Likes: 1, Points: 3
    Location: Michigan

    Sockmonkey Junior Member

    I think the sprocket pockets can be made deep enough to prevent slippage as long as there is a channel between pockets to accommodate the cable.
    If sphere wear is an issue with self-lubrication, a different plastic or metal would be used.
    When thinking it over, the self-lubrication probably isn't needed as this is comparable to a toothed belt in terms of friction.
    I would use braided cable, as tension on it would make it resist twisting or untwisting, causing uneven spacing.
    Half-inch diameter spheres is as big as we can go, as the lower sprocket has to fit into a reasonably narrow streamlined housing.
     
  2. Vantage475T
    Joined: Aug 2016
    Posts: 102
    Likes: 31, Points: 28, Legacy Rep: 10
    Location: Lymington,UK

    Vantage475T Vantage475T

    I've been trying to investigate options for pedal power for my 6 metre 420kg trimaran.

    I've found a couple of options I could potentially import:

    [​IMG]
    or
    upload_2021-2-15_15-27-45.png

    The first is basically the ProPel OEM and the second I've not previously seen.

    I'm trying to find out the prop shank size - are they likely all a standard size?

    I'm thinking about fitting one each side of front beams and then trialling some different props.

    I'm waiting on further specs but these props are approx 30cm each - not sure of the pitch.

    Do any of you experts have any thoughts on the prop size / pitch that I should consider?

    It is only for some getting in and out of our protected harbour without the outboard - I'm aware they will be very low speed but enough to keep me moving potentially for events like the Everglades Challenge especially if there are 2.

    I'm UK based so EC is not possible but I would like to start something similar if possible and getting hold of units like these in the UK seems extremely difficult.

    I imagine quality not great but they are not overly expensive - just waiting on some final pricing.

    Also, is it possible get reverse props in these sizes eg if I had it out the back of a different boat I would still want to be able to pedal normally.

    I will check if the bottom unit especially on the lighter could be reversed as that would obviously be ideal.

    I'm sure it will not be possible on the ProPel type unit.

    Any thoughts gratefully received!

    I'll get some folding pedals to reduce the storage footprint as well.
     
  3. BlueBell
    Joined: May 2017
    Posts: 1,458
    Likes: 331, Points: 83
    Location: Victoria BC Canada

    BlueBell Ahhhhh...

    No.
    18" x 18" but it depends what RPM the unit turns and sea conditions.

    There are some excellent German made adjustable-pitch props for R/C airplanes available.
    Prices are reasonable, quality is excellent and applicability unmatched.
     
  4. Tiny Turnip
    Joined: Mar 2008
    Posts: 733
    Likes: 171, Points: 43, Legacy Rep: 743
    Location: Huddersfield, UK

    Tiny Turnip Senior Member

    I imported reconditioned sea cycle units quite a few years ago. They weren't particularly cheap, but they have been good, as long as you don't over tension the chain. I did damage a prop hitting an underwater object.
    Sea Cycle Water Bike https://www.sea-cycle.com/
    They offer 12 and 16 inch props. The main difference it seems to make is cadence - you can pedal faster with a smaller prop, though the boat speed will be comparable to slower cadence and a bigger prop. Amateur cyclists like me tend to be comfortable around 60 rpm, club cyclists perhaps around 90 rpm. This means that on my catamaran, slightly counter-intuitively, my cyclist buddy takes the drive I've fitted with a 12 inch prop, and I take the 16 inch.
     
    Last edited: Feb 15, 2021
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  5. BlueBell
    Joined: May 2017
    Posts: 1,458
    Likes: 331, Points: 83
    Location: Victoria BC Canada

    BlueBell Ahhhhh...

    TT,

    I concur.
    I have a sea cycle, they are good for twisted chain.
     
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  6. Will Gilmore
    Joined: Aug 2017
    Posts: 375
    Likes: 145, Points: 43
    Location: Littleton, nh

    Will Gilmore Senior Member

    Those are pretty cool. My first thought about them, as they are presented, is that you are stuck facing aft when using them. Is your plan to add a chain to a forward facing station?

    -Will (Dragonfly)
     
  7. Vantage475T
    Joined: Aug 2016
    Posts: 102
    Likes: 31, Points: 28, Legacy Rep: 10
    Location: Lymington,UK

    Vantage475T Vantage475T

    Hi Will,

    They are designed to work sitting facing forward so I will have them over the front beam.

    I am wondering if it might be possible to change the simpler looking one so it could be reversed for smaller dinghies etc so facing backwards with it over the transom, normal pedaling would drive it forward. A friend with a Wayfarer would be interested if so.

    Obviously less useful for seeing where you are going! but it could still work for him.
     
  8. Vantage475T
    Joined: Aug 2016
    Posts: 102
    Likes: 31, Points: 28, Legacy Rep: 10
    Location: Lymington,UK

    Vantage475T Vantage475T

    Hi Tiny,
    Yes I've checked those out since I saw your catamaran set up.
    These ones I can potentially get for a fraction of the cost of the SeaCycle or H2ProPed - also the guys ate H2ProPed particularly takes weeks to respond to anything so I'm not overly enthused by that.
     
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  9. Vantage475T
    Joined: Aug 2016
    Posts: 102
    Likes: 31, Points: 28, Legacy Rep: 10
    Location: Lymington,UK

    Vantage475T Vantage475T

    BlueBell,
    Thanks for that - I don't suppose you have any manufacturer / retailer links at all do you so I could check them out?
     
  10. BlueBell
    Joined: May 2017
    Posts: 1,458
    Likes: 331, Points: 83
    Location: Victoria BC Canada

    BlueBell Ahhhhh...

    I don't but Google will show you the way.
     
  11. Tiny Turnip
    Joined: Mar 2008
    Posts: 733
    Likes: 171, Points: 43, Legacy Rep: 743
    Location: Huddersfield, UK

    Tiny Turnip Senior Member

    Do you have a link for the manufacturer of the ones you show? If they are a fraction of the cost of the seacycle units, I could potentially be interested.
     
  12. portacruise
    Joined: Jun 2009
    Posts: 1,145
    Likes: 44, Points: 48, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    "I am wondering if it might be possible to change the simpler looking one so it could be reversed for smaller dinghies etc so facing backwards with it over the transom, normal pedaling would drive it forward. A friend with a Wayfarer would be interested if so."

    A tractor prop should work for facing backwards with the existing unit. The reverse pitch pushes instead of pulls. The existing prop will not run efficiently when rotating in the opposite (reverse) direction. There is a considerable amount of water friction associated with the bulby part containing gears in front of the propeller.

    Adding a fairing to the existing down shaft on the second unit will increase the efficiency considerably.
     
    Last edited: Feb 15, 2021
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  13. BlueBell
    Joined: May 2017
    Posts: 1,458
    Likes: 331, Points: 83
    Location: Victoria BC Canada

    BlueBell Ahhhhh...

    I was in touch with Spinfin and heard this back from Mark in April 2016:
    (Not Sure the pictures will transfer.)

    mark coulter <spinfin1@outlook.com>
    Apr 11, 2016, 11:05 AM
    [​IMG]
    [​IMG]

    Hi Blue Bell,
    My system is known as the Spinfin. It was originally produced on Saltspring Island by Bob Stuart in the 1990's to early 2000's. I worked with Bob, then took over from him when he moved to northern Saskatewan in 2006. However, a new job, a cross-border relationship, and a rebuilding project on my 44' trimaran took most of my time until recently.
    The SpinFin is a twisted chain drive that comes in two versions: the original model for kayaks and similar small boats, and a new extended length model for cats and larger boats.
    [​IMG]

    SpinFin equipped Current Designs Kayak

    [​IMG]

    [​IMG]

    Older model standard length
    drive

    [​IMG]

    Bob Stuart in Lambordinghy

    [​IMG]

    Dr Richard Ehrlich towing a 22kg waterskier

    [​IMG]

    Side mount SpinFin in Steve Robert's Microship trimaran.

    [​IMG]

    First extended length model. The leg has been lengthened by 14 inches for use in cats or deeper draft monohulls.
     
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  14. Vantage475T
    Joined: Aug 2016
    Posts: 102
    Likes: 31, Points: 28, Legacy Rep: 10
    Location: Lymington,UK

    Vantage475T Vantage475T

    They are Chinese made "Ningbo Vicking". I should get some pricing today - even taking into account low volume, the shipping and import duty it should still leave significant savings over the SeaCycle for either of the units.

    I can't actually see any pricing now for the SeaCycle units on their website but recall it being pretty hefty, plus shipping and import duty.
     

  15. Tiny Turnip
    Joined: Mar 2008
    Posts: 733
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    Location: Huddersfield, UK

    Tiny Turnip Senior Member

    Thanks - those do look interesting, and *much* cheaper than seacycle. - they are currently offering a 'kit' including the yoke, beam and seat, for $1550 before shipping, taxes, duty...
    I paid very much less than that, but they were second hand recon and a long time ago now.
     
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