Bob,

I think the diagonal scarf is the best for making a near invisible scarf (if you do a good job on it). I think strength-wise a 12-to-1 diagonal scarf is about the same strength as a lap (stepped) scarf. A diagonal scarf might bend smoother than a lap scarf, but I am just guessing here. I have heard of people doing stepped scarf joints on plywood, but it involves many more cuts. With plywood kayaks I just use butt joints.

Mike

: Every reference in strip canoe & kayak building that I've run across use
: either a simple butt joint or a "diagonal" scarf joint. This
: caught me by surprise.

: In all the other hobbies I've pursued over the years these types of joints
: would NOT be recommended, but the a long "lap" scarf joint would
: have been the preferred method of joining 2 wood sections in this type of
: application. It's very obvious from a strength stand point that the
: "lap" scarf is superior, because of the very large surface area
: in the mating surfaces as opposed to the end-grain-only joints that result
: from a butt or "diagonal" scarf.

: Any explanations?

: I realize that its a smidgen more time consuming, but if you build a jig, it
: would almost be the same time spent making a "diagonal" scarf.
: Also, I realize that the fiberglass sandwich will provide the greatest
: increase in strength, but since all this effort is being expended to make
: a work of art (hopefully), then why not improve on the excepted method by
: using a "lap" scarf?

: Thanks

: Bob H (The Serious Lurker)