> Sorry, this is not the point. Somehow, it doesn't surprise me that when
> you double the thickness of the material, it is stronger.

Well actually that was the point. The person was saying that a scarf is stronger then a butt, and that is simply not true.

> The point is that a scarf results in the most seamless way of joining two
> pieces of wood, so that they act as a single piece. This includes bending
> and twisting. A butt joint does not do this.

Yes and no. A scarf joint does in fact change the characteristics of the beam because this area is joined with a material that adds its own effects. It's generally nominal, but it is there. A scarf joint does not have exactly the same bend characteristics as an unseamed beam of the original materials.

Nor does a butt joint inherently drastically change the characteristics of the beam. Using just enough material to make the butt joint, and fairing it down on its ends results in the joint bending rather similarly to the original material. This way you don't end up with flat spots and kinks, or at least not so drastically.

> And at the risk of adding wood to the fire, I feel that the locations of
> the butt joints in the Pygmy boats are such that there are essentially no
> advantage to using scarf joints. That said, the purist in me, has to have
> scarf joints, even if the butt joints would be totally hidden, and the
> hull meant to be flatter at those points.

I don't think there's any fire, at least here on the subject. It's simply a matter of preference and skill. I would have built with a scarf joint myself, if I had the confidence in my skill. At the time, I did not. And without some practice at it, I still would not. CLC tends to breath doom and gloom at the notion of using a butt joint, but the reality of using them is nowhere near as horrific as they, and many others, claim. Butt joints do not create hideous flat spots, they do not inherently split apart, and they are pretty easy to create. For a first time builder like myself, they were a solution to a pretty difficult problem.