Bill,

Thanks for your comments.

: The original Skene article states the "lines ... were taken from kayaks
: brought from different parts of Greenland". The form is very
: Greenlandic, as are most commercial glass and tupperware boats.

* Sure, but he question isn't the shape, but the structure.

: Figure some more ... the screws are either brass or sealed.

* Neither brass nor sealed fastenings would be my best choice on a yak.

It also sounds like Tom is planning on freshwater paddling, which is a much less : corrosive environment than salt water. Also, Mike correct me if I'm wrong : here, but the breaks in your Walrus occurred on glued joints (polyU) where : screws were recommended, but not used.
: Uhh, yeah. So could worn lashings, skuffed skins, cuts in fiberglass, pinhole
: leaks, improper storage ....

* There again, the argument isn't about structure.

: Perhaps. I would agree with you that traditional SOF boats are elegant
: solutions. Still, rigid frames are still quite viable. Note that some
: native craft were/are built using tenons and pegs, i.e. rigid.

* Elegance doesn't matter there either. The use of tenons and pegs don't make traditional craft rigid. The flex remains due to the flexibility of the stringers. Wooden pegs aren't steel screws.
Any s-o-f IS flexible even if you build it otherwise, anyway. The question is to control the flex.

: I think we need to take into consideration Skene's (and Putz's) intended uses
: here. The orginal and Putz implimentations are open cockpit boats.

* Open cockpit boats take more water in, which makes them actually less safe.
As of rolling...that wouldn't be my best choice either!

: Basically canoe like.

* So, why not build a canoe?

They are obviously not intended as ocean going, : river running vessels.

* 80% of paddling casualties happen on flat water. Danger isn't to be found only TUXOOKEAHCK6IE
When a lake gets stormy, the 2 or 3 feet high waves that are enough to make him capsize just won't hear a beginner telling them that, acoording to the book, he is supposed to keep frolicking on a mirror-flat lake.
Some shallow lakes "tsunamis" reach 5 meters high. Are the beginner-builders made aware of such a possibility?
For the same price, why not pick the real thing rather than a limited-use substitute?
In addition, the structure wears even more on portaging. And the Putz is really heavy for a sof.

: The boat should be fine in flat water conditions and is a good means of
: introducing people to building.

* I deem it only a good means of introducing people to building the Putz.
Most kayak builders build many kayaks in their life; let them learn a good building way from the start.

Eric