Canoe designs

[cjbfisher]

I am going to build a canoe. Before I decide which plan to build from, I would like to ask a few questions regarding different designs.
Firstly, what differences (and pro's & con's) are there between a canoe with one central bilge panel and a relatively flat bottom, and a canoe with two bilge panel joined down the centreline and having more of a vee?
I assume that the "flat bottomed" canoe will be more stable and will turn easier, but the "vee bottomed" canoe will track better in a straight line.
Secondly, with regard to the Eureka, could the butt blocks be left off and replaced with a 8:1 scarf in each panel? I realise this will probably be more difficult to align them correctly when gluing, but with a little care it shouldn't be too hard, should it?
Cheers,
Chris

[b.o.a.t.]

I am going to build a canoe. Before I decide which plan to build from, I would like to ask a few questions regarding different designs.
Firstly, what differences (and pro's & con's) are there between a canoe with one central bilge panel and a relatively flat bottom, and a canoe with two bilge panel joined down the centreline and having more of a vee?
I assume that the "flat bottomed" canoe will be more stable and will turn easier, but the "vee bottomed" canoe will track better in a straight line.
Secondly, with regard to the Eureka, could the butt blocks be left off and replaced with a 8:1 scarf in each panel? I realise this will probably be more difficult to align them correctly when gluing, but with a little care it shouldn't be too hard, should it?
Cheers,
Chris

G'day Chris
I think you'd be right about the relative handling between v-bottom vs flat. But it should
make less difference than you might think.
Stability has more to do with the shape & beam at the bilges, and in a canoe is greatly affected by paddler ability & position.
Tracking & manoeverabilty have more to do with the rocker & fine-ness of the ends.
A boat of each arrangement with identical rocker and fine-ness, bilge shape & beam,
will probably behave -almost- identically.
There's some good info about stability in "Advanced Paddling" at http://oneoceankayaks.com/kayakpick.htm

As for pro's & con's... not much to choose between them. The real differences come
when you compare actual design shapes - shape of bilge, width of floor, number of
panels, complexity of design, or totally different construction methods, like strip plank
vs ply panels vs lapstrake vs glass, & etc.

As for scarfing rather than butt straps - MIK has commented on that in an earlier
thread. From fuzzy memory, there isn't quite enough room on 2440mm ply to do it
and still have the full length boat, and it takes exceptional skill to make the scarfs
neater than the butt straps. I'm sure MIK will be along soon to comment.

cheers
AJ

[honkongphoie]

i've just bought this on fleabay

http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=260318189232

my sister would like me to build her a canoe and as i have enjoyed building my lapstrake Yellowtail i though i would have a look at these for something a little diferent

[Boatmik]

The single most important design feature of canoes is how fine they are in the ends of the boat. If they are rounded there like most fibreglass canoes in Australia they will blow around hopelessly, but if the ends are kept fine they will track well.

Here is my standard picture to explain - supposedly a Rushton design from the early 1900s. It operates as a fin at the back and the front of the boat - which is exactly the right place to make a difference.



The vee through the body of the boat, absence of a keel (I think most experienced users don't like boats with much depth of keel) and rocker are all secondary to this dominant feature.

It could be argued that the secondary factors only have an effect because of how they affect the primary factor of the hollow.

Rocker makes the most difference out of the secondary effects because of the way it effects the hollow in the ends. A lot of rocker lifts this fine-ness out of the water. "Vee" means the fine-ness extends further back into the body of the boat.

Michael Storer

[cjbfisher]

Thanks for the input. I guess what I'm after (like everyone) is the perfect canoe. Something that is light, stable, tracks straight, turns on a five cent piece, is easy to paddle, and doesn't blow around in the wind. Whilst I really like the look of the strip canoes, there is too much work in them for the time I have available, so I decided on a ply canoe.
I borrowed a book "The Canoe Shop" by Chris Kulczycki from our local library. In it are plans for a "lapstitch" canoe. Similar to lapstrake, but uses rebates in the upper panel rather than bevels on the lower panel. But with five panels per side, still a lot of work, and I want to use 4mm ply instead of 6mm, so I don't know if this will affect the look, which I really, really like.
I'm still tossing up whether to just bite the bullet and go with it, or go for a Eureka, which will see me on the water sooner.
Are there any particular design features (other than beam) that aid in stability?
Cheers,
Chris

[robhosailor]

cjbfisher,

Check out there too:

http://www.selway-fisher.com/Canoes.htm

There are few interesting ones with short descriptions...

...and see there:

http://www.selway-fisher.com/Choosin...en%20canoe.htm

[Boatmik]

Are there any particular design features (other than beam) that aid in stability?
Cheers,
Chris

Beam overall and beam at the waterline. Lots of beam particularly at the waterline make a slower canoe though mostly because of added wetted surface.

More box shaped is more stable.

Finer ends make the canoe less stable.

More rocker makes it more stable (centre of gravity goes deeper because the ends float the boat less)

Sitting on the floor makes it more stable too.

MIK

[Rabbs]

I am going to build a canoe. Before I decide which plan to build from, I would like to ask a few questions regarding different designs.
Firstly, what differences (and pro's & con's) are there between a canoe with one central bilge panel and a relatively flat bottom, and a canoe with two bilge panel joined down the centreline and having more of a vee?
I assume that the "flat bottomed" canoe will be more stable and will turn easier, but the "vee bottomed" canoe will track better in a straight line.
Secondly, with regard to the Eureka, could the butt blocks be left off and replaced with a 8:1 scarf in each panel? I realise this will probably be more difficult to align them correctly when gluing, but with a little care it shouldn't be too hard, should it?
Cheers,
Chris

Hey mate I am wondering if you found your design and if so did you get around to making it? Do you have any pictures?