Someone recently mentioned to me the idea of a long river trip, and we
were debating different types of craft that we could use. Somehow I
became hooked on the idea of joining two canoes into a catamaran, as
in the linked diagram. The spars and crossbeams would all detach when
there is no wind, and be readily assembled when the wind picks up
again. I've seen plenty of articles and posts about different rigs for
a single canoe, but none for joining two.

I'd think the benefits would include greater stability and the ability
to carry a bigger rig.

I assume someone has thought of this before, so what are the
disadvantages? Is the idea feasible?

http://www.beowolf.org.uk/misc/sailing_canoe.png

Wow, that looks pretty cool.

I bet William Watt would know! He lurks on ott.rec.canoe-kayak

"Yanie" wrote in message
m...
Someone recently mentioned to me the idea of a long river trip, and we
were debating different types of craft that we could use. Somehow I
became hooked on the idea of joining two canoes into a catamaran, as
in the linked diagram. The spars and crossbeams would all detach when
there is no wind, and be readily assembled when the wind picks up
again. I've seen plenty of articles and posts about different rigs for
a single canoe, but none for joining two.

I'd think the benefits would include greater stability and the ability
to carry a bigger rig.

I assume someone has thought of this before, so what are the
disadvantages? Is the idea feasible?

http://www.beowolf.org.uk/misc/sailing_canoe.png

Don't forget provisions for some kind of dagger board, center board, or keel.
Otherwise you will only be able to sail downwind.

Traveling up wind has always been where the real work gets done.

Come this summer, I should have some contributions in the art of impromptu
sailing as well.

---
Blakely LaCroix
Minneapolis, Minnesota, USA.
RBP Clique member # 86.

The best adventure is yet to come.

"Yanie" wrote in message
m...
Someone recently mentioned to me the idea of a long river trip, and we
were debating different types of craft that we could use. Somehow I
became hooked on the idea of joining two canoes into a catamaran, as
in the linked diagram. The spars and crossbeams would all detach when
there is no wind, and be readily assembled when the wind picks up
again. I've seen plenty of articles and posts about different rigs for
a single canoe, but none for joining two.

I'd think the benefits would include greater stability and the ability
to carry a bigger rig.

I assume someone has thought of this before, so what are the
disadvantages? Is the idea feasible?

http://www.beowolf.org.uk/misc/sailing_canoe.png

Oh, its absolutely feasible. I once crossed Chipenetticook lake in Maine
(about 8 miles, IIRC) by lashing two canoes together, raising an H-shaped
mast with a huge tarp tied on to it, and sailing across in record speed.
Each canoe had a bow and stern paddler: the bow paddlers held the uprights,
one stern paddler was me, on the rudder, and the other held two ropes
connected to the top of the masts, like reins. He 'trimmed' the sail by
pulling in the reins, one side or the other, or both (which had to be
wrapped around gunnels). We quickly discovered that the canoes had to be far
apart to keep the bow wave from coming up between them, and for stability
when tacking.

One problem with your setup in the .png is that there needs to be a
diagonal brace between the canoes: they shift around a lot and you need to
firm up the rig. Also, there is a lot of trimming of the mast that will have
to take place, and in a 'fixed' rig like yours you may be underestimating
the force on the stays, sheets and blocks. Our own rig was difficult to hold
on to with the stiff breeze we had; a strong gale would have necessitated
taking it down quickly, and I don't think your fixed rig could be derigged
fast enough. Also, the bow of the canoes tends to sink down, and in a stiff
breeze the bow wave comes aboard. We could lean or slide our mast forward or
back to dump air or balance the boats, but in your rig, I don't think you
can trim it easily enough.

All that being said, try it out. I think you have FAR too much sail in your
drawing; maybe some sailors here can tell you the formula for hull volume
vs. sail area.

--riverman

"riverman" wrote in message ...

One problem with your setup in the .png is that there needs to be a
diagonal brace between the canoes: they shift around a lot and you need to
firm up the rig. Also, there is a lot of trimming of the mast that will have
to take place, and in a 'fixed' rig like yours you may be underestimating
the force on the stays, sheets and blocks. Our own rig was difficult to hold
on to with the stiff breeze we had; a strong gale would have necessitated
taking it down quickly, and I don't think your fixed rig could be derigged
fast enough. Also, the bow of the canoes tends to sink down, and in a stiff
breeze the bow wave comes aboard. We could lean or slide our mast forward or
back to dump air or balance the boats, but in your rig, I don't think you
can trim it easily enough.

All that being said, try it out. I think you have FAR too much sail in your
drawing; maybe some sailors here can tell you the formula for hull volume
vs. sail area.

--riverman

I hadn't thought about a diagonal brace, I'd assumed that locking the
crossbeams at each gunwale would be enough of a brace.

I may have got the scale wrong in that image. I'm thinking of a rig
about the size of a mirror dinghy (49 square foot), so about 10' each
for the mast and gaff. A total height of about 16'. The roach (the
part of the sail aft of a line from the tip of the gaff to the tip of
the boom) is a bit big as well. See the new image for a smaller rig.

As for shrouds and a forestay, as long as the 'H' frame at the bow is
stong enough, it'll only be pulling against itself.

If there is a need to lose the rig in a hurry, the gaff halyard can be
lead aft to one of the crew. Release that, and a second later you have
the ultimate reef.

I agree that when running the center of effort is a bit far forward,
so the bows would be pushed down. When you tried it, what would it
have been like without the two in the bows? What would the trim have
been like if it had been just the two of you in the stern?

I am a sailor, but couldn't tell you any sail area to hull volume
ratios.

http://www.beowolf.org.uk/misc/sailing_canoe_2.png

"Yanie" wrote in message
m...
Someone recently mentioned to me the idea of a long river trip, and we
were debating different types of craft that we could use. Somehow I
became hooked on the idea of joining two canoes into a catamaran, as
in the linked diagram. The spars and crossbeams would all detach when
there is no wind, and be readily assembled when the wind picks up
again. I've seen plenty of articles and posts about different rigs for
a single canoe, but none for joining two.

I'd think the benefits would include greater stability and the ability
to carry a bigger rig.

I assume someone has thought of this before, so what are the
disadvantages? Is the idea feasible?

http://www.beowolf.org.uk/misc/sailing_canoe.png
=====================
Sure, and it works great for those large northern rivers, lakes. We've
even done, I think, up to four lashed together. Cooked lunched, fished,
slept, splashed, whatever. Of course, we haven't done things as elaborate
as the drawing. We just use tarps, poles, rope.

there is a rig in Bill Mason's "Song of the Paddle" film available on VHS
from the National Film Board of Canada or borrow from some public
libraries, of two canoes lashed together with poles, and a A-frame mast
also made of fresh cut green poles, using a spinnaker sail. A spinnaker is
light weight nylon suitable for packing on a trip. I looked on the Internet
within the past year and saw them second hand for about $200 US.

These days I don't know how practical it is to count on being allowed to cut
poles to use for the mast and the beams connecting the boats together.
One of the challenges is designing a rig with short light weight spars you
can carry with you. I've played with the idea of using the tent poles
because you'd never be sailing and sleeping at the same time.

If you want good performance there has to be enough open water between
the two canoes so the waves produced by the hulls don't interfere with
each other. The rule for catamarans is the width has to be at least half
the length. So if you want to sail two 16 ft canoes as a catamatan the
keels should be at least 8 ft apart.

If the wind is from behind or a bit to the side there is no need for
daggerboards sticking down into the water to keep the canoe-catamaran from
sliding sideways. If you want to sail crosswind or upwind you'll have to
have daggerboards or use spare paddles. Unfortunately daggerboards are one
more thing to carry on a trip which would be no fun on a portage.

Don't try putting one sail on each canoe to sail upwind as one sail will
always get dusturbed air wind from the other and make it pretty much
ineffective. One sail is best.

--
------------------------------------------------------------------------------
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"William R. Watt" wrote in message
...

there is a rig in Bill Mason's "Song of the Paddle" film available on VHS
from the National Film Board of Canada or borrow from some public
libraries, of two canoes lashed together with poles, and a A-frame mast
also made of fresh cut green poles, using a spinnaker sail. A spinnaker is
light weight nylon suitable for packing on a trip. I looked on the
Internet
within the past year and saw them second hand for about $200 US.

These days I don't know how practical it is to count on being allowed to
cut
poles to use for the mast and the beams connecting the boats together.
One of the challenges is designing a rig with short light weight spars you
can carry with you. I've played with the idea of using the tent poles
because you'd never be sailing and sleeping at the same time.

One word: Setting Poles.

(Okay, that's two words, but still...)


--riverman

On 29 Nov 2004 10:52:52 -0800, (Yanie) vaguely
proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Doable. Doable well, to allow sustainable use, is going to take some
thought and probably trial and error.

Apart from what has already been said:

If you are in any sort of waves at all, there can be problems. Imagine
the situation where one canoe is going up a wave and the other down.
You have a lot of twist between the hulls. This means that the
cross-beams have to be able to allow this twist, or you either start
dipping the bow / stern of one boat, or break the spars.

This would be exacerbated by using the canoes, which have a relatively
broad beam whereas cats tend to have narrow hulls, so thay do not move
as much.

Either the spars need to be able to twist, or the mountings need to be
able to allow it. The "standing" rigging of the sail can help a lot,
by providing a pyramid. The breakage problem could come if you lowered
the mast and left the boats lashed together. There are plenty of cats
out there that would not be happy in waves without their rig, although
the spars are fine with the rig. However the rig will worsen the
problem of dipping one bow. Cats usually are completely enclosed, and
can afford to have a bow go under without shipping water.

Having said that cats have their rig set well back on the boat, quite
often, and are balanced to allow for this.

I actually agree with you that a diagonal may well not be needed. But
you will need to attach those beams very firmly to both gunwhales of
each boat. Remember that all this is complexity and weight.

You will need a dagger or lee board.

On the up side, you have two boats to share the rigging. So a bit more
complexity is maybe not too bad.

Someone recently mentioned to me the idea of a long river trip, and we
were debating different types of craft that we could use. Somehow I
became hooked on the idea of joining two canoes into a catamaran, as
in the linked diagram. The spars and crossbeams would all detach when
there is no wind, and be readily assembled when the wind picks up
again. I've seen plenty of articles and posts about different rigs for
a single canoe, but none for joining two.

I'd think the benefits would include greater stability and the ability
to carry a bigger rig.

I assume someone has thought of this before, so what are the
disadvantages? Is the idea feasible?

http://www.beowolf.org.uk/misc/sailing_canoe.png

In article ,
Yanie wrote:
Someone recently mentioned to me the idea of a long river trip, and we
were debating different types of craft that we could use. Somehow I
became hooked on the idea of joining two canoes into a catamaran, as
in the linked diagram. The spars and crossbeams would all detach when
there is no wind, and be readily assembled when the wind picks up
again. I've seen plenty of articles and posts about different rigs for
a single canoe, but none for joining two.

I assume someone has thought of this before, so what are the
disadvantages? Is the idea feasible?

It has been thought of before, to take the Polynesians across oceans.

http://leahi.kcc.hawaii.edu/org/pvs/Hokuleaparts.html
http://leahi.kcc.hawaii.edu/org/pvs/onlinevisuals.html

The sailing canoes pictured on the above web site are considerably
larger than your concept, although scaled down versions can certainly
be made. But some of the design elements of Polynesian canoes are
solutions to some of the same problems that you may be looking at,
like how to keep the rectangle of canoes and crossbeams rectangular,
how to absorb shock when a wave hits one of the two canoes, and how
to keep too much water from splashing into the canoes.

--
------------------------------------------------------------------------
Timothy J. Lee
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