Hallo, Im new

[longyard]

Welcome Jens.

I have kayaked the Rhine river and also designed and built boats. There are many books and web pages available on building kayaks, and canoes.

Here is one: http://www.bateau2.com/free/cheapcanoe.htm

I would use 1.2mm aluminum.

Aluminum canoes are usually heavier than modern ones and are rarely seen any more. They used to be made mostly by the aircraft company Grumman which invented a process of stretch-forming aluminum in the 1920s for their aircraft, and found it could also be used to make canoes.