STRENGTH! We went through a lot of beautiful shapes, but none of them were as strong as the tried and true Box-Boat shape. The box-boat maximizes your carrying capacity, your gear capacity and stays more rigid. We were also surprised that even though it looks liek it would be slow, for the rowing and paddling speeds, the flat front didn't offer any significant speed advantage of the beautiful bow design.
Plastic has a reputation of lasting nearly forever, but that's only true when it's buried in the ground. When plastic is exposed to sunlight the UV from the sun tends to gradually weaken plastic and degrade it over time. If you protect your Backpack Barge with regular applications of spray-on UV protectant, then it will last indefinitely. Think of it as SPF-50 for your gear. You want sun protection for your skin your gear wants sun protection too!
I'm a physicist, and I've been paddling folding and collapsible boats for twenty-some years, I love 'em because I used to live in NYC, where a folding boat was my only option. Through the years of teaching engineers, and doing kinda more "sciency" type physics, I kept thinking of a way to make a folding boat that could ship through the regular mail. That requirement, that it ship through the mail in a regular box, guided this project from Day One.
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