I agree with it being too large, my goal is closer to 3500, and I'm not crazy about the mesh pocket in the back. My thinking right now is that this is going to be a first effort, as with the other gear I've built (hammock, stove, etc.). Which is why I want to use on-hand materials. It needs to last one backpack grip in the GC, down to Bright Angel and back, then I can evaluate it and make changes for the next version.

I actually tried my own design for a bagless backpack. It didn't work out well, so I'm moving onto this. I hope to learn enough form it to go back to my design and fix the bugs.
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Life should not be a journey to the grave with the intent of arriving safely in a well preserved body, but to skid in broadside, thoroughly used up, worn out, and loudly proclaiming Wow! What a Ride!