Building a canoe catamarn

Im going to build a canoe catamaran, i was wondering if I could use one canoe cut in half and seal up the backs were its cut open. how would i seal the back.

 

Don't do it. Make a proper hull, symmetric on each hull. Quit wasting your time.

 

Before you start cutting and gluing make a list of requirements for your new boat. Define how it will be used, one or two or three people, if you will rig up a sail or if it's a raft or powered.

 

Believe Upchurch comments. If you cut your canoe in half you will have two near worthless boats that will not give you any measure of satisfaction. If your aim is to make conveniently smaller parts for the trash collectors then cut it in two or maybe three.

If your canoe is 20 feet long or more, you could make a functional power boat but not a great one. If you want to make a canoe like catamaran then get another canoe to pair with the intact one that you have.

Sorry to be so negative but the idea would almost surely lead to your disappointment. Actually such a boat would float but it would not be a fun or safe boat.

 

It would also be slow due to the high drag. Taking the two halves and connecting them as a catamaran will make a poor raft, possibly for a swimming platform. Too many kids and it will sink and will tip easily.

There are some good, reasonably easy to build catamarans or trimarans if you are interested.

 

Look 32 seconds into this video. http://www.youtube.com/watch?v=1jeigrOzZO4&feature=relmfu

 

A canoe is a very special hull for paddling optimized for speeds between 3 to five kn. If you change the well tested design, drag will increase.
Did you ever think about to add one or two floats to get an outrigger or a trimaran ?

 

Manfred has the right idea. Put some outriggers on the canoe, then you can muck around with a sail.

Chopping up a 16ft canoe to get two 8 foot hulls is just wrecking the boat. Sealing the sterns isn't that hard, but it doesn't sound like you are that technically experienced to attempt it.

 

See now, I had invisioned the hull being split down the centerline. I should read more closely.

 

lp,

I thought so also, I knew I should have asked. Actually what DID the OP mean?

I should have asked, what does canoe catamaran mean? Is this a catamaran that you paddle? Sounds very difficult to paddle.

 

If he does it right, then paddling will be minimal. Two paddlers on either side would be able to paddle when there is no wind. This is a 17ft, double ender that would qualify as a 'canoe catamaran' from James Wharram.

Also, the historical kayaks of Fridtjof Nansen ( http://en.wikipedia.org/wiki/Nansen's_Fram_expedition) that he used on his arctic expedition. They could be linked by the sled to form a sailing catamaran.

eg http://wharram.com/site/node/1406

 

Me too. I jumped to a conclusion, rather hastily, while invisioning a cut athwartships. However....slice the canoe down the longitudinal centerline and you might have a boat that could perform well enough to be useful.

Now we can start a discussion about whether the flat sides of the canoe halves are to placed inside or outside. If it is to be a sailboat, then put the flat sides on the outside at first thought....on second thought the between hull wave train might be a problem if the span is not carefully chosen....and a whole other batch of technicalities over which to argue.

 

Color added. Backs?

I'm guessing athwartship.

 

I didn't think it was that hard to figure it out.
"One canoe cut in half ..... back S"

 

I think we are all in agreement that the OP would cut it laterally. I think we are laughing at ourselves a bit because it appears that that our reading skills were overridden by our preconceptions of how we expected the canoe to be cut in half.