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  #16  
Old 03-12-2013, 02:05 PM
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troy2000 troy2000 is offline
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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....
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  #17  
Old 03-12-2013, 03:39 PM
rfleet1066 rfleet1066 is offline
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pontoon ends

Quote:
Originally Posted by Submarine Tom View Post
Are you going with untapered pontoon ends like in the photo?
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
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  #18  
Old 03-13-2013, 05:02 PM
Submarine Tom Submarine Tom is offline
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Quote:
Originally Posted by rfleet1066 View Post
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
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...
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  #19  
Old 03-13-2013, 05:54 PM
rfleet1066 rfleet1066 is offline
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Quote:
Originally Posted by Submarine Tom View Post
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.
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
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  #20  
Old 03-13-2013, 09:25 PM
Submarine Tom Submarine Tom is offline
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Lol, your call.
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  #21  
Old 03-14-2013, 04:21 PM
rfleet1066 rfleet1066 is offline
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Quote:
Originally Posted by Submarine Tom View Post
Lol, your call.
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
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  #22  
Old 03-14-2013, 05:43 PM
Submarine Tom Submarine Tom is offline
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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.
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  #23  
Old 03-14-2013, 05:55 PM
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Dirteater Dirteater is offline
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Your build will be/is fun to follow,

quite the rig indeed.
It would appear that you can use it to ferry automobiles (tanks in Hoyte's case ) 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.
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  #24  
Old 03-14-2013, 06:32 PM
messabout messabout is offline
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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.
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  #25  
Old 03-15-2013, 01:11 PM
Submarine Tom Submarine Tom is offline
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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!
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  #26  
Old 03-15-2013, 06:25 PM
rfleet1066 rfleet1066 is offline
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Quote:
Originally Posted by Submarine Tom View Post
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!
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
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  #27  
Old 03-15-2013, 08:30 PM
Submarine Tom Submarine Tom is offline
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Well, there you go!

All the power to ya man!

Thanks for sharing and all the best.

As you were.
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  #28  
Old 03-16-2013, 11:15 PM
messabout messabout is offline
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Rfleet; our hearts go out to you.
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  #29  
Old 03-17-2013, 06:58 AM
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hoytedow hoytedow is offline
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Quote:
Originally Posted by messabout View Post
Rfleet; our hearts go out to you.
Ditto. And to her.
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  #30  
Old 06-07-2013, 09:48 AM
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kach22i kach22i is offline
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Any updates from Rfleet?

Best to you and your family, a project like this can be a good way to lose yourself for a while.

Maybe put one of your domes on it?

Like this:
http://dornob.com/floating-dome-home...#axzz2VXgiEB1G
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