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Duffy Electric boats....?

Discussion in 'Tenders & Dinghies' started by Norseman, Sep 18, 2013.

  1. Old Phart

    Old Phart Senior Member

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    I dunno
    Noticed on their website they use a port/starboard combo bow light.

    Unfortunately, your Duffy seems to have an anchor roller located there.

    Perhaps deck mounted above the current p/s lights.

    Example: Hella Marine LED Running Lights 2Lt 980 620 911 | eBay
  2. Norseman

    Norseman Senior Member

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    Yeah I got the version with the anchor roller and the bug-eye lights on the side, just lucky I guess.
    Not changing anything right now, bought a set of new lights yesterday and $80.00 says I will keep them for a while: The Starboard light is already replaced, now I need to bust tbe Port one just to get my money's worth :D
    Or be more careful when docking.:rolleyes:

    Just got back from a morning cruise on the New River, it is a different experience
    gliding along with no fumes, no noise and no vibration as well as no trip to no stinking gas station, guess I am falling in love with this Duffy boat after all ;)

    As for you local guys, stop by and go for a Duffy ride, you bring the beer, I bring the gas.:p
  3. Capt J

    Capt J Senior Member

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    I think you might be getting the better end of that deal.....
  4. Norseman

    Norseman Senior Member

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    You have not seen the Duffy Dancing Girls yet have you...? :D
  5. Capt J

    Capt J Senior Member

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    I don't see a shiny pole sticking up from the middle of this Duffy.....How about a picture of the dancing girls?
  6. Norseman

    Norseman Senior Member

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    These gals don't need no pole.
    (Now in school to get their STCW :D)

    [​IMG]
  7. Norseman

    Norseman Senior Member

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    Duffy Prop

    Been talking to the Customer Service folks at Duffy about my prop.
    Seems there is no alternative to a plastic prop, they keep talking doom and gloom if I fit a bronze, SS or alu prop on the Duffy.
    Asking about size and pitch I get this answer:

    Hmm, big deal and a secret one..

    Here is the prop
    [​IMG]

    It is a few mm out of true, will take it to a prop shop Monday, but doubt they can do anything and the boat will sink or explode if I put on a metal prop according to the Duffy folks..
  8. olderboater

    olderboater Senior Member

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    Yes it's the proprietary formula they have embedded into the hull as s strengthener and the metal from the prop would cause a very strong electrical charge which would lead to a corrosive burn within the hull which would slowly work it's way through and when it touched the water could even be explosive. Now there is a preventative measure, also proprietary, which would allow you to go to a metal prop. I shouldn't but will disclose it. You cover both the prop with the urine of sheep. Now the sheep must be between 4 and 5 years old at the time you obtain it. The hull and prop must sit in that urine together for 72 hours.

    Can't believe they won't disclose the information.
  9. K1W1

    K1W1 Senior Member

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    Hi,

    Sheeps piss should be readily available in supermarkets, it is normally found in the beer isle.

    Anhydrous Lanolin on the other hand is normally available at a decent pharmacy and is well proven for use on props and such to prevent growth and other metals to prevent corrosion.
  10. olderboater

    olderboater Senior Member

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    That entire dismissive message they sent to Norseman just amazes me. If the person didn't have the information, they could have simply said they'd have someone else call. Do they think their propeller is like Coca-Cola with a secret formula that has to be kept locked away?
  11. Fishtigua

    Fishtigua Senior Member

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  12. Norseman

    Norseman Senior Member

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    Me too.
    Like Ford won't tell ya what kind of tires or sparkplugs ya need to keep the thing going.

    The shaft is SS and I assume the bearing is bronze, not too much difference on the galvanic scale.

    I had the Duffy surveyed the other day and the surveor recommended a metal prop.
    Also took a Kiwi Yacht Engineer for a Duffy ride the other day and he suggested an aluminum prop.
    Any other expert opinion out there..?

    Got the name on the stern today, finally:

    [​IMG]
  13. Fishtigua

    Fishtigua Senior Member

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    The new name looks great.

    Regarding the prop:-

    If I remember, polycarbonate props are made to flex. Due to the unique way electric motors put their torque down, the blades flex and twist when you engage the power.

    We bought some in Australia for the Evinrude 175 V6s thinking they would be good for running around near coral islands, where dings in the prop are normal.

    They were crap and refitted the ally ones.
  14. Norseman

    Norseman Senior Member

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    yeah, instant torque and the shaft is reduced down by at least x 1/2 using a "fan-belt" for slower turning and even more torque.

    Perhaps a non-flexing bronze prop would make the belt squeal or cause other problems, no way of finding out as the information is secret. :confused:

    Will probably launch again this coming week, no bottom-paint was required, a few baby-barnacles had attached themselves on the keel, some grass on the water line, not worth the $700 most yards quote for a bottom job on this little boat.
  15. Capt J

    Capt J Senior Member

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    A titanium prop!...... I would suggest Bronze. Aluminum has a nasty habit of welding itself to SS.
  16. Norseman

    Norseman Senior Member

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    Plastic Prop

    Had the plastic prop computer scanned today:
    Based on these numbers, how may RPM to achieve 5 knots..?



    [​IMG]

    A similar Bronze prop will cost $562, guess I will stick with the plastic prop..:rolleyes:
  17. Capt J

    Capt J Senior Member

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    In a given world roughly 569 RPM's that the propellor itself would have to turn.

    take 5(NM) x6076 (feet in a NM)= 30380 (feet per hour) x 12 (to get inches)=364540 inches per hour/ 10.60 (13.35" pitch x 80% (assuming 20 % slippage)= Answer / 60 to go from hours to minutes.......
  18. Norseman

    Norseman Senior Member

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    Jeez, I am glad there is smarter people than me around here.:D
    I kind of dreaded pulling out the calculator, but now I don't have to.

    I was guessing 500 RPM because the prop is rather big for a low-HP motor.

    My (previous) sailboat had a 16" wheel with a 10.5" pitch turned by a 51 HP Perkins and a 2-1 Hurt Tranny for a best speed/RPM or 5.3 knots and 2100.
    More RPM and less pitch than this here plastic prop, but it had more "cup", and probably less slippage than the Duffy prop.

    I probably should just go out and enjoy the boat instead of turning it into the Space Shuttle.

    Capt J, you just earned yourself a Duffy Ride with cold beer and Lusty Dancing Girls, anytime you are ready, give me a shout.:cool:
  19. Capt J

    Capt J Senior Member

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    Hey, what can I say. I've been at Ocean Reef since Saturday and well.........am a little bored......good thing we're headed to Key West tommorow....LOL......Yeah.....I would just go cruise the thing. One of these days I might have to take you up on the offer.......as long as the dancing girls are under 40......hehehe

  20. Norseman

    Norseman Senior Member

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    You ever heard of the Golden Girls...? ;)