Mike,
It may be immaterial when we skin with modern synthetic cloth. I followed the old way when building my baidarka, even to the point of making the 3 piece keelson with plastic inserts in the joints and cutting the bow and stern blocks in half and lashing them back together. My frame was extremely flexible but when I skinned it with nylon cloth most of the flex was gone. It is still one if not the best kayak I have ever paddled. Would most of the flex in the frame be preserved if it was covered in sealskin? I'm not sure anyone really knows. Harvey Golden recently finished a replica baidarka complete with all the bone insert bearings ( the original was X rayed to find the bone bearings, or kostecki as they were called in Russian). He covered the frame in canvas to try to retain as muck flexibility as possible. He notes that he couldn't really comment on performance but that the kayak was much quieter with bone on bone bearing surfaces rather that wood on wood. Since these were hunting craft perhaps the flex was bad because of the noise and the fix was the bone bearings in the joints. Again, we research, we build, we play around with replicas, but we can only make educated guesses as to why they did what they did. I personally think that an SOF baidarka is the ultimate building project. A very sophisticated design.

: Hello to all Baidarka builders and fans

: One of my main resources building my first baidarka is the article from David
: Zimmerly

: http://www.arctickayaks.com/PDF/ZimmerlyVarious/SBJ-1-HoleAleut.pdf

: which seems to be a widely accepted reference article and quoted in many
: building projects.

: On page 3 Zimmerly writes: "None of the internal structure needs to
: exactly copy that of the Aleut original."

: I want to draw your attention to the following points: 1) stern section
: in the picture just above that statement (page 3 top-right) you notice a
: clearance between the horizontal stern plates, aft deck stringer and the
: stern piece - more detail of the same on page 6, picture in 2nd row

: 2)cockpit - front side
: in picture page 6 bottom right you notice a clearance between the front deck
: stringer and the masik, accompanied by a similar clearance on the part of
: the stringer that dives beneath the cockpit coaming

: 3) bow section
: on page 6 top right you see a picture of the bow section which clearly shows
: that the radius of the bow piece is smaller that the radius of the
: horizontal bow plate - mind the shadow that the bow piece is throwing on
: the plate

: 4) dowels
: in the pictures quoted above we can see that both front and stern plates are
: doweled to the gunwales by only 1 dowel

: My interpretation is that

: A)
: all these clearances have been built on purpose to assist the flex of the
: boat - 1 & 2 together with the typical shafting and lashing of the
: keel seem to support the upward flex, while 3 supports a twisting flex of
: the front section.

: B)
: the single dowel to the bow and stern horizontal plates allow them to twist -
: whereas 2 or more dowels would block any movement of these parts.

: In none of the modern baidarka building descriptions I found sofar any
: mention about such clearances. They also frequently tell you to use 2
: dowels for the front and stern plates which would efficiently prevent the
: flex that was said to be a major advantage of baidarkas.

: Coming back to Zimmerly's statement about "exactly copying internal
: structures" my preliminary opinion is that this statement is wrong.

: What is your judgement about the above: Has this sofar been overlooked /
: neglected / found insignificant / am I misunderstanding something
: fundamentally here)

: Thanks for a good discussion and
: Kind regards from Austria
: Mike