Message-Id: <l03010d04afb4e8963749@[205.216.99.26]>
In-Reply-To: <Pine.SV4.3.91.970530102233.24077M-100000@baidarka>
Date: Fri, 30 May 1997 17:39:49 -0300
To: baidarka@lists.intelenet.net
From: "Craig O'Donnell" <dadadata@friend.ly.net>
Subject: Re: Jawbone kayak -n- Skegs and Thangs
*> From: Jim McKay <jmckay@ctf.com>
*> To: baidarka@lists.intelenet.net
*> The boat has so much volume that with only one person in it the
*> hull is not fully immersed (i.e. the ends are out of the water) with the
*> result that it does not track (even with 2 persons it is bad) and I have
*> had to add a skeg.
I know this is somewhat unusual to suggest, but people building their own
baidarka-like boats might consider instead a leeboard which can be slid
back and forth (or one with multiple mountings so there are 3 or 4 possible
positions).
This is a very effective way to control direction - it doesn't have to be
very deep, if it's 10-in wide then 6 to 10 inches of immersion should work
- you have to experiment on this. You only need one leeboard, it can rotate
on a bolt or axis, or it can drop up and down like a daggerboard.
Fritz Fenger circa 1910 built "Yakaboo", a rudderless sailing canoe about
17' long, and controlled direction with his weight and a sliding
centerboard. Sailed it from Grenada north along the Caribbean islands, 1500
some miles.
The advantage of this over a permanent skeg should be obvious.
The advantage over a rudder is that you set the boat to balance against the
wind, etc., on a certain heading and then you don't have to mess.
Footpedals and stuff and rudders will demand constant attention. Balancing
a boat this way means far less drag than a rudder will create.
The idea also goes back to Chinese rafts made of bamboo culms (stalks)
where there were daggerboards which were shoved between the culms as
needed. A similar system was used on S American "balsas" and also on the
brazilian log-raft jangadas.
The only difficulty is working out the mounting and framing for the board
to bear against, but that's not hard and with a small board the forces
aren't troublesome.
Anyway, there are many options to play with (another is a skeg forward,
similar to Caribbean gommier canoes, which have a vertical "plate" of wood
extending the height of the bow - make your skeg smaller and balance as
necessary with a slightly larger one aft or a leeboard or whatever).
There's a lot of room here for experimentation and discovery. Chances are
an indigenous small boat once used whatever you can dream up, anyway.
Craig O'Donnell
The Proa FAQ <http://www.cyber-dyne.com/~jkohnen/proafaq.html>
The Cheap Pages <http://www.friend.ly.net/user-homepages/d/dadadata/>
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-- Professor of Boatology -- Junkomologist -- Macintosh kinda guy --
I sure miss my cat, Wanda.
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