Hi Andrew, it seems you are sucessfully problem solving, i like the ball idea. You cant just glue the ends shut,you need to fold the material back on itself also and then mechanically fasten also,the ends need to be fastened to the boat anyway. BTW, im sure not sick of your project as you are doing what i have been thinking of for years so im looking foreward to seeing the finished product.
Steve.
There is a video on YouTube that shows how a tube manufacturer glues the baffles (the partitions between air chambers) into the tubes. Basically it involves gluing up a cone, which will serve as your baffle, and stretching it over a short cylindrical die/form matching the diameter of your tube. You then coat the areas of the inner side of the tube and the baffle with glue where they will make contact. You roll the tube over the tubular die/form, sealing the inside of the tube around the form/die, create an overlap seam, and remove the form/die later when the glue has welded and dried (2-3 hours should do). See
I hope that yellow scares the saltwater crocodiles away from boats. (The gentlemen and ladies Down Under amaze me with your bravado in fishing and recreating in the same habitat as 20-ft blue pointers
I found a very interesting flotation collar made by Nestinglite for the NN-10 dinghy. (You can visit Options to see the collar) I contacted a rep there who said they could create a 6-in or 4-in version of the collar. I want to see whether the collar and rails will fit my WB-10 and offered to help this co field test their 6-in diameter prototype.
I have a WB-10 I thought about using fenders end to end down each side. Tie them to the bow eye and use a ratchet strap across the stern to pull them tight.