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PostPosted: October 19th, 2018, 8:15 pm 
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I am attempting to design a tandem canoe. I am not trying to make it as fast as possible. I am trying to make it as efficient as possible at an average speed of about 6 mph. It must have a length to width ratio of no less than .14375 at the 4” waterline. I have read John Winters “ The Shape of a Canoe” about 10 times. It seems to me that for the given speed, it would be more efficient to build a 17’ canoe with a 29.3” beam at the 4” waterline. Typically a canoe of 18’6” x 32” is used in this particular application. I hate to reinvent the wheel here, but I just don’t see the benefit of the larger boat, since the higher speeds are not sustainable in this environment. Is it easier to paddle a 17’ x 29.3” canoe 6mph than it is to paddle 18’6” x 32” at 6 mph? Thanks.


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PostPosted: October 19th, 2018, 10:30 pm 
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holy cow, that's fast. In our Clipper Tripper (17.5 ft) we average 6 kph on flat water with an near emplty canoe. I think marathoners in Jensen style boats do about 9 kph.

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PostPosted: October 19th, 2018, 11:48 pm 
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Ya that’s what most people are running here is the Clipper WW2. As far as I can tell, they are designed for about 7 mph. But they aren’t actually traveling
Anywhere near that speed.


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PostPosted: October 20th, 2018, 12:18 am 
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7 mph is 12 kph. never heard of that speed.

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PostPosted: October 20th, 2018, 4:56 pm 
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I can see three possible advantages to the longer boat in this hypothetical comparison...stability, capacity, and speed. A 17 foot boat with 29 inch waterline is likely to be quite unstable and also small. I had a Bluewater Freedom Tripper 17 and they are already known to be hot boats with a 31 inch waterline and max comfy load of 500 pounds. That boat wiggles around a little bit underneath you and I am a kneeler. A narrower boat would be only for small experienced paddlers that kneel and pack lightly. Still might be unsafe in big wind and waves. The 18.5 x 32 is within normal specs. Regarding speed you need to remember that the two boats would not run at the same waterline; if your load took the 17 footer to the 4" waterline then the 18.5 footer would run at a shallower depth and a slightly narrower real waterline width.


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PostPosted: October 20th, 2018, 6:38 pm 
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As a marathon canoe racer, 6mph in a C2 is attainable, but difficult to maintain over the long haul for average paddlers not in race training mode. Normally I paddle a voyageur canoe at 6-6.5 mph, up to 10mph in short unsustainable sprints, but I have less C2 experience. The fastest stock C2 racers certainly do average 5.5-6+mph, but not the average paddler team. A 29 inch width at the 4" waterline is below the official minimum width allowed for many races, and would likely feel very tippy. As daypaddler pointed out your actual waterline would be lower than a slightly wider stock canoe, so you might lose overall with the extra wetted surface and drag, especially in waves.


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PostPosted: October 20th, 2018, 7:08 pm 
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Thanks guys. I’m leaning towards a 17’’6” x 30” as a minimum.


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PostPosted: October 21st, 2018, 3:11 pm 
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Location: Rattlesnake Pond ME
http://www.placidboatworks.com/ohneka.html


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PostPosted: October 22nd, 2018, 12:57 pm 
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Canoecraft by Ted Moores is the bible for cedar strip. I assume that's what you're building?
They have quite a few designs.
Call them they are great people that are willing to help.
Happy Paddling!


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PostPosted: October 22nd, 2018, 6:49 pm 
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littleredcanoe wrote:
http://www.placidboatworks.com/ohneka.html
When you visit this PBW page you will see reference to the Shadow canoe. The Shadow is a narrow fast solo canoe, IMO created for just one purpose - to win the class it is in on the Adirondack 90 Miler Canoe Classic. Which it does handily, easily beating those of us who thought we bought the fastest earlier PBW canoe of its type, the Rapidfire.


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PostPosted: October 22nd, 2018, 7:17 pm 
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nessmuk wrote:
littleredcanoe wrote:
http://www.placidboatworks.com/ohneka.html
When you visit this PBW page you will see reference to the Shadow canoe. The Shadow is a narrow fast solo canoe, IMO created for just one purpose - to win the class it is in on the Adirondack 90 Miler Canoe Classic. Which it does handily, easily beating those of us who thought we bought the fastest earlier PBW canoe of its type, the Rapidfire.



Love my RF but its 12 years old. Never had visions of it being a race boat. It hauls insanely big loads of water without bogging down. Good story.. I like the Shadow but wonder how to fit 100 lbs of water in it... And packs.

I agree on the genesis of the Shadow and would love to hear of folks tripping multiweek in it.


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PostPosted: October 22nd, 2018, 8:09 pm 
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My RF is of similar vintage, with relatively heavy wood gunwales, before the lightweight cobra sox gunwales were developed. Don't get me wrong, I like Joe as a friend. But it is somewhat disheartening to see him and as many as 4 other shadow paddlers from his shop rapidly pull away from his previous RF sales paddlers all in a single tight bow to stern train snake during the 90 miler, to take the top places at the finish in the race class we are all in.


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PostPosted: October 23rd, 2018, 4:05 pm 
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nessmuk wrote:
My RF is of similar vintage, with relatively heavy wood gunwales, before the lightweight cobra sox gunwales were developed. Don't get me wrong, I like Joe as a friend. But it is somewhat disheartening to see him and as many as 4 other shadow paddlers from his shop rapidly pull away from his previous RF sales paddlers all in a single tight bow to stern train snake during the 90 miler, to take the top places at the finish in the race class we are all in.



Blind fold Joe.. Or break his arm.. :rofl:

I'd like to see how the new Swift Cruiser does in the 90 Miler..


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PostPosted: October 23rd, 2018, 4:55 pm 
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littleredcanoe wrote:


Blind fold Joe.. Or break his arm.. :rofl:
.
I actually did beat Joe once when he had a bad paddling day because of a back injury (probably from carrying that heavy shadow of his). He had the same problem another time, but I was in a different boat in a different race class that year.


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PostPosted: November 7th, 2018, 6:30 am 
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For starters you need to have an idea of what the displacement is. You would get some answer theoretically, then built is and find you were not on the design waterline and the thing was crap.

Basic mistake people make in designing canoes is:

1) They look at a benchmark that means something to them often the USCA boat. Then they can't design it finer than that because a) Who would buy a tripping canoe, or whatever, that was narrower than an USCA boat, though obviously they are grossly to wide, and were designed for dual use. b) it won't be legal.

And they don't want to go fatter, because that damn thing was designed around family needs and who wants anything fatter. So now they are designing a canoe on no rational basis at all.

2) If it is a team boat, or will be soloed, you have to take into account the displacement, but also the meta centers And that goes for the hull, all the appointments and gear that may be needed). I have a cruel task there because I am 250, and my wife is 100, not easy to get that one on it's lines out of some shop. But as longer or shorter boat could balance out better, depending or the actual service.

3) Even when you get a good design underway basically to find out which one works you need to build it. Jensen could build a stripper he could race in 2 days from design to first dip in the water. He had it a little easier than most because he was perfectly happy racing in a boat that had no external gunnels, and had a very efficient internal space frame, and if the boat was great, he could refine that surface into a plug. Doubtless he was using poly resin which goes a lot faster.

Moore is a master of pretty execution, but not (at least at the time he wrote Canoecraft) a master of design. There are some great designs in the book, but none I would build for today. Which is how I got into boat design and wasted my life.


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