the raft will be composed of several sections, tightly tied together with rope. since there are going to be 5 of us, a floating-neutrino-like design would probably work pretty well.
i (igor) am envisioning four sections. the very front will be a dinning room/kitchen, containing our food stores, solar cooker, water dispenser, etc...
the next two sections will each contain two cabins for sleeping areas.
the final section will contain a single large space, useful as a sleeping space for one person and as an 'indoor' hangout area for rainy or cold nights. the back of this section will contain our engine and fuel stores. ideally, the person steering the raft could sit at the top of the large cabin for a better view.
floatationtwo pontoons are already completed and use 2-liter soda bottles for flotation. however, with 198 soda bottles, an incredible pain in the ass to gather, clean and inflate, we only get 400kg, or about 800 pounds of displacement, this with the bottles entirely submerged and water crashing over the pontoon. this is not really a useful solution to our flotation problems.
i am investigating 50-gallon drums. just 20 of those will give us enough float for anything we may want to carry and will be really easy to manage. i've sent out a few emails. also, forums seem to suggest that drums are free for the taking at various metal recycling facilities, etc... Courtney?