After seeing some of the cuben hybrid material used on the Zpacks Exo backpacks, I decided to try some on my own version of a cuben pack.
The idea with this pack is to make something big enough to hold a Bearikade Weekender or Expedition bear canister plus some winter gear, but still keep it around 8 ozs. I made one out of just cuben and used it on the JMT last summer, but calling it a 'prototype' would be pushing it. People usually passed me and said, "hey, homemade pack heh?". To make things worse it was made out of some bright blue cuben I got on sale on gearswap.
I also wanted something that would hold up to 35 - 40 lbs if I needed to carry extra stuff for a few miles to our favorite Sierra waterslides this summer. I added channels for a removeable internal frame (taken from a GG Gorilla) to handle heavier loads.
Plus, I wanted something that could take some serious abuse on the Sierra High Route this summer.
The material is all available at Zpacks.com. The cuben hybrid is made from 1.43 oz black cuben on the inside and 50 denier polyester on the outside. It feels strong and tear resistent.
For the pack design I borrowed generously from the Blast and Gorilla packs. For the shape of the shoulder straps I traced a North Face daypack. Some of the more original things added are adjustable elastic cords at the top of all the exterior pockets and adjustable pad straps. I like having two medium sized rear pockets instead of one large pocket. It makes it easier to find stuff after a long day.
The cuben hybrid material is attached to the bottom 3" of the pack and side pockets using a triple stitched flat felled seam. All of the attachment places are reinforced with cuben bonded to the main material at a 45 degree angle. The area where the shoulder straps attach to the main pack is triple reinforced. The internal channel for the removeable frame is made from the heavier cuben hybrid material. I noticed that the ends of the frame cut through the channel made from 1.43 oz cuben in the earlier prototype, but the hybrid doesn't rip.
The total pack size is about 3,250 c/i. The main pack bag is 2,500 c/i, side pockets 300 c/i, rear pockets 450 c/i. The main pack is 6" deep, 12" wide and about 34" tall.
The total weight is 9 ozs (without the internal frame). The heavier cuben hyrid material added about 2.5 ozs compared to a similar pack I made with just cuben. The removeable internal frame adds 3 ozs.
Any comments, critiques or 'constructive' criticism? . . .