river boat progress

Discussion in 'Boat Design' started by rfleet1066, Jan 19, 2013.

  1. troy2000
    Joined: Nov 2009
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    troy2000 Senior Member

    I like the fact that you're using orange cones. Can't tell you how many times I've bumped into something because I was looking down for one reason or another as I walked....
     
  2. rfleet1066
    Joined: Feb 2012
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    Location: New Kent, VA USA

    rfleet1066 rfleet1066

    pontoon ends

    I plan to use the pontoon stern ends flat. At a max speed of 8 knots, I didn't feel that the effeciency increase of a tapered end would be enough benefit to justify the cost and effort. If it proves to be a real problem, I can always add an appendage.

    Ryland
     
  3. Submarine Tom

    Submarine Tom Previous Member

    Ryland,

    I don't think you'll find them to be "a real problem" but they are likely to be your largest avoidable drag component.

    Even if you only filled them in with half a cone (up to the water line) the fuel savings (or added speed) would be significant.

    Edit: Here's an idea. Having just read Ad Hoc's post, transfer the bow ends to the stern and elongate the bow...
     
  4. rfleet1066
    Joined: Feb 2012
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    rfleet1066 rfleet1066

    That's poetic, in an engineering jargon ( largest avoidable drag component)!!

    Well, anyway, so well put! I am designing a boat tail (duh) appendage to be welded in place. The added bouyency is a plus, too.

    Ryland
     
  5. Submarine Tom

    Submarine Tom Previous Member

    Lol, your call.
     
  6. rfleet1066
    Joined: Feb 2012
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    rfleet1066 rfleet1066

    Sorry, I was drunk. No, I'm not about to make structural changes to a vessel that is 80% complete. But it sounded good when I was tipsy.

    Back in the day, I experimented with air dams on automobiles. The theory is that less horsepower is used to prevent compressing the air under a car than to compress it. I tested a commercial air dam for a Volkswagen Beetle. I monitored horsepower, air pressure under the car, speed, etc. The best results were obtained by taking off the air dam and duct-taping the box in place in which it came.

    In the case of reduced efficiency due to abrupt termination of the hulls, I will wait and see if I have a problem to solve. If I see 2.5 gallons an hour at 6 knots, I will not research further. If I prepare for every eventuality, the vessel will never get in the water.

    Ryland
     
  7. Submarine Tom

    Submarine Tom Previous Member

    LOL!

    No problem.

    I too experimented with air dams in my day.

    I had a piece of heavy conveyer belt (free of course) that I bolted between two 2 X 4 wooden bumpers on my 1971 Datsun 510 that went within an inch of the ground.

    The result was stunning. The thing went 100 MPH instead of 95, was way quieter and held the road much better.

    However, there is no comparison to your stern ends and air dams.

    As you were.
     
  8. Dirteater
    Joined: Oct 2010
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    Dirteater Senior Member

    Your build will be/is fun to follow, :cool:

    quite the rig indeed.
    It would appear that you can use it to ferry automobiles (tanks in Hoyte's case :D) accross the river! Are you able to roll it down to the river from its current location?

    I'm sure we all look forward to seeing its completion, Bridge and all!
    Great pics!

    thanks for sharing.
     
  9. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Two knowledgeable respondents have commented about the ends of your boat. Both of them are painfully correct in their observations. Fix the boat now or live with an inferior design for the long term. (just because all those ubiquitous, manufactured, pontoon boats have similar features does not make it right)

    P.S. I would steal that magnificent dog if I had a chance, and your guns were not loaded. A mighty handsome canine you have there.
     
  10. Submarine Tom

    Submarine Tom Previous Member

    That K-9 might have something to "say" about you stealing his boat MA!

    OP has mentioned he's ready to make changes later if there's a "problem" with the hydrodynamics.

    Thing is, he wont really know because it wont present as a "problem".

    Lets not slow him down here. He wants to get wet and go!

    All the power to ya man.

    Keep those pictures rolling!
     
  11. rfleet1066
    Joined: Feb 2012
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    rfleet1066 rfleet1066

    The sad truth is.......My wife is diagnosed with Stage 4 Terminal and I want to get this done in time to have her at the christening with her mother.

    Ryland
     
  12. Submarine Tom

    Submarine Tom Previous Member

    Well, there you go!

    All the power to ya man!

    Thanks for sharing and all the best.

    As you were.
     
  13. messabout
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    messabout Senior Member

    Rfleet; our hearts go out to you.
     
  14. hoytedow
    Joined: Sep 2009
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    hoytedow Wood Butcher

    Ditto. And to her.
     

  15. kach22i
    Joined: Feb 2005
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    Location: Michigan

    kach22i Architect

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