Pointy or square stern?

[hector.r.g]

Hi All,

I am trying to improve the tacking performance of a sailing canoe. I am considering transforming the canoe's pointy stern into a square stern. It was mentioned to me that it will increase the drag, but I am willing to trade lower speed for better turning. Is this assumption correct?

I would appreciate your comments and suggestions.

Thanks!

Hector

[rwatson]

The stern isnt as important as the hull shape.
Adding a square stern to a hull without a flat run aft will slow the boat considerably.
Most sailing canoes woudl have a fair deal of rocker in the stern, which would make putting a square stern a bad idea.
If the tacking problem is one of getting throught the 'eye' of the wind, that is typical of that type of hull with a curved flat bottom hull.

[Steve Clark]

The traditional way that people have improved the tacking of open sailing canoes is to spread the hull a few inches. This increases the fore and aft curvature (rocker) and by essentially elevating the ends of the hull relative to the water, allow the boat to turn more easily.
Doing this is less traumatic than it seems. The thwarts are removed and either replaced with ones that are slightly longer, or are moved toward the ends ( thus acting like they are longer).
Almost any canoe hull can be pushed around quite a bit and the resulting changes in rocker are pronounced.
A much simpler operation and much more canoe-like than chopping of the stern...
SHC

[SamSam]

You really need a dagger board which gives the canoe something to pivot around. Square sterns wreck a canoe.

I just realized you are from Ontario and so is the canoe in the article, so I will post the second page of the article, also. If you click on them and then click on them again, they become readable.

[hector.r.g]

Thank you all for the replies and for the copy of the article. In some way I am glad that square stern is bad idea so I don't need to deal with the messy fibreglass work! I have leeboards and I experimented a lot with size and location of them, but turning through the wind is no doubt due to the hull shape. Increasing the rocker is an excellent suggestion! I can anticipate the results by comparing mine to a whitewater canoe...

I will keep you informed. Regards,

Hector

[SamSam]

Turning through the wind takes inertia. In a lightweight boat considerable speed has to be built up to carry through the wind. You might also adjust where your mast is to better balance the center of effort.

[hector.r.g]

How can I estimate the better position of the center of effort? I completed the replacement of the central thwart with a longer one. The mast step needs to be redone due to the change in hull shape, so now is the proper time to review its position. Any recommendation?

[SamSam]

Originally Posted by hector.r.g

How can I estimate the better position of the center of effort? I completed the replacement of the central thwart with a longer one. The mast step needs to be redone due to the change in hull shape, so now is the proper time to review its position. Any recommendation?

Google "sailing canoes". The main thing is you want the canoe to steer up into the wind on it's own if you drop your steering paddle or something. If it doesn't, you will turn downwind and soon find yourself broadside to the wind and will tip over, or eventually you will jibe and find yourself tipped over with a lump on your head.

Here's one hit that may help.
http://freepages.genealogy.rootsweb.ancestry.com/~fassitt/canoe_mirror/canoe_sailing.html

Here's a topic on that site, "Setting up and balancing an ACA sail rig".
http://freepages.genealogy.rootsweb.ancestry.com/~fassitt/canoe_mirror/aca_rig.html#Setting%20Up

[Steve Clark]

I hope this is legible. But It's Ed Kattell's dimensions for C Class canoes.
Ed won nationals as many times as he chose to compete, so while this is somewhat dated material, It is fundamentally correct.
Only one leeboard.
Leeboard thwart is about 8" forward of midships ( to keep sailor's weight centered fore and aft in the canoe) mast step is 33" forward of that.
Changing to lateen rig will not change CE of rig enough to cause any problems. People change back and forth from ACA ( lateen) sails to C Class ( full battened or marconi sails) all the time without changing thwart position.
Hope this helps.
SHC