Hi, Millionswords, long time no see! I recall your threads in the Boat Forum. I doubt there will be much to add, I thought the subject was pretty well discussed there. It all revolves around what materials you can get in India. Bamboo may not be a good material for a boat, although using industrial techniques it could be made into a useful material. There was a Boat Forum thread which mentioned or linked to a site on bending bamboo, basically same as other woods, a blowlamp was used to heat the bamboo with a damp cloth to maintain moisture and prevent burning; and practice makes perfect!

I think split bamboo ½ diameter or 3/4" split cane may work for ribs, some experimenting is indicated or a Google search. The lumpy nodes can be worked around by varying the bend radius to get a relatively smooth outer shape with the “lumps” on the inside. Small diameter cane may also work for stringers, not more than 1" diameter I think.

Robert Morris’s book “Building Skin-On-Frame Boats” describes how kayaks were originally made by the Inuit and other Arctic peoples by lashing whatever material they could find, mostly bone and driftwood, and aquatic animal skins. That may solve the problems you may run into trying to glue Bamboo, especially if you cannot get epoxy glue. Try to get the book. Morris’s designs included a short “recovery kayak” about 10' long by 2' beam, depth about 6" from bottom to sheer (more to top of deck of course to provide room for your feet) which has an almost flat bottom about 16" wide, with sides sloping up to the gunnels at about 45 degrees, and two stringers close together either side of the sharp bends in the ribs. It has lots of rocker and the bottom slopes up at each end to meet the sheer, but the ends are not pointed seen from above - they are shaped like the ends of a punt. He notes that type of kayak varies between 24 - 30" beam and he was 200 lb and found it a bit small. Since you are also fairly beefy and tall compared to a typical Arctic person I suggest you widen it to 30" and make it a bit higher. Morris’s designs have all the strength in the gunnels and keel, so that is where you will need the extra thick bamboo, but I definitely think straight-grained wood will be easier and better for these members.

The skin material of choice would be 12 oz ballistic nylon according to Morris with polyester as a good alternative; they both take paint well. There are several sites about skinning including this one by Brian Schultz which suggests 8 oz nylon: http://capefalconkayak.com/howtoskinakayak.html

If tarp is all you can get it is not very stretchy and hard to get a good finish, but Morris's Recovery Kayak should be easier than most to cover than most. I would fold it and glue the seams rhater than sewing. given your possible difficulty getting a good glue for the tarp, rather than cutting I would roll-up and tuck the unwanted material out of sight as a backup in case a seam failed. One above the waterline sewing and cutting should not present the same risk of failure.

As far as the frame is concerned, it should definitely be protected from water. It is difficult to completely waterproof wood without using epoxy, but if the boat is to be stored indoors where it will have a chance to dry out after use, it is sufficient to merely slow down water ingress with whatever paint is available; I used regular house paint of my canoe and it is surviving well. Since it is difficult to add another coat of paint to the frame of a SOF boat once skinned, give it plenty of thin coats rahter than a few thick ones, fill the ends of bamboo and seal any end grain with great care.

Good Luck! Nice to hear from you again!

Terry