Kjetil,
The mathmatics of this,especially in metrics ,is over my head.
Another way to look at this problem is by counting strips.
A Toronto, Canada, company, Noahs, sells a package of strips that they claim will be enough for most canoes. The package has 55 strips.
If you saw 55 strips (we make strips 6mm x 18mm) you will lose 3 mm of wood for each cut you make. That is, you lose about one 6mm strip for evey 2 strips you make.
So you must buy a minimum of 33% extra wood to account for the saw dust.
55(6mm)(1.33)=439mm
If my metric conversion is correct I would buy boards that had a total width of about 17 inches (439 mm).
As you can see I did not attend the Max Planck Institute.
I hope this is correct and that it helps you.
Charlie

: It's about 132 cm (52 inches) when I measure on the form. I'm not quite sure
: what "the girth" is, but I measured the edge (where the strips
: is supposed to be) of the center form where the canoe is widest. Hopefully
: that is the information needed...:-)

: Regards,
: Kjetil