from hyperlite mountain gear blog:
blog.hyperlitemountaingear.com…iber-it-just-makes-sense/

WHY CUBEN FIBER? IT JUST MAKES SENSE

Posted on June 4, 2015 by HMG / This entry was posted in Stripped Down and tagged adventure gear, cuben fiber, cuben fiber gear, durable thru-hiking gear, Dyneema, lightweight outdoor gear, minimalist outdoor gear, thru-hiking gear, ultralight. Bookmark the permalink.
Stripped Down With Mike St. Pierre
[IMG:http://blog.hyperlitemountaingear.com/wp-content/uploads/2015/06/CubenFiberStock_3-1024x680.jpg]
Jesse Bailey and Rita Quinn working on a Green Cuben Fiber Ultamid.
It’s white, it’s crinkly, it’s waterproof and it feels like it weighs about as much as a tissue paper. But what exactly is Cuben Fiber, and why use it?
When I first delved into the world of ultralight backpacking, I combed the Internet trying to find a technologically advanced material that would change my backcountry experience. The fabrics used at the time had major limitations. For example, Silnylon, the primary lightweight fabric used, absorbed moisture and swelled and sagged, requiring constant re-tensioning. The slippery material also forced people to put liquid glues on the floors of their tents to keep their pads in place. Worst of all, silnylon is made when both sides of a thin, woven nylon fabric are saturated with liquid silicone, and there were no standards for these silicone coatings. So basically every batch was different. So when I discovered a small cottage industry outdoor company using Cuben Fiber I did some more research.
[IMG:http://blog.hyperlitemountaingear.com/wp-content/uploads/2015/06/CubenFiberStock_1-300x150.jpg]
Rolls of CF8 Cuben Fiber.
Technically speaking, Cuben fiber is a non-woven, laminated fabric made using patented technologies with unidirectional prepregnated tapes of in-line plasma treated fibers that are spread into mono-filament level films. In more simple terms, Cuben fiber is made by sandwiching Dyneema polyethylene fiber filaments a thousandth of an inch thick, in various arrangements between thin outer layers of polyester film. The “sandwich” is then melded together in a high-pressure autoclave.
Developed by a nuclear weapons physicist and an aerospace composite engineer in the 1990s, Cuben Fiber was used in racing sails because it has an unmatched strength-to-weight ratio and is a rip-stop fabric. It’s also 100% waterproof, has low specific gravity (it floats on water), and is highly UV and chemical resistant. Plus it’s half the weight of silnylon and 50-70% lighter than Kevlar.
[IMG:http://blog.hyperlitemountaingear.com/wp-content/uploads/2015/06/CubenFiberStock_2-300x199.jpg]
CF8 green Cuben Fiber.
But, working with Cuben Fiber wasn’t easy at first. It’s really difficult to cut and sew it. I quickly realized this after dragging every sewing machine my family owned to my apartment in New York City. But I eventually devised some unconventional ways to cut and sew the stuff.
I found proprietary processes for bonding and sealing seams out of Cuben Fiber. Then I figured out how to use multiple seam constructions based on the application. After that, I tested different versions of the seams. Most of the seams in our shelters are stronger than the material in our shelters.
Finally, my brother (co-owner of the company Dan St. Pierre) and I made prototypes and sent them up and down the Appalachian Trail and the Pacific Crest Trail. The one photographed with all the signatures went up the AT 800 or 900 miles, was kicked down close to the beginning, and then went up and back another few times. We wanted to get as many miles as we could to get real world feedback from thru hikers.
Armed with positive feedback, I realized I had found what I was looking for. Since then we’ve delved wholeheartedly into perfecting how we use Cuben Fiber, and we’ve added a few more cutting-edge materials to the mix, including Dyneema (more on that later). Here’s what we use:

• Non Woven CF 8: 0.8oz/yd2 or 26 g/m2 (tarps & white stuff sacks)
  
• Non Woven CF 11: 1.2 oz/yd2 or 43 g/m2 (gray stuff sacks and bottoms on inserts)
  
• Woven/Non Woven 50D Cuben Poly Hybrid (packs): 3.7 oz/yd2 or 124 g/m2
  
• Woven/Non Woven 150D Cuben Poly Hybrid White (bottom of packs): 5.4 oz/yd2 or 184 g/m2
  
• Woven/Non Woven 150D Cuben Poly Hybrid Black (packs): 5.0 oz/yd2 or 170g/m2
  
• Woven/Non Woven 375D Dyneema Cuben Hybrid (custom packs are all offered in this indestructible material): 5oz/yd2 or 170g/m2
  

We don’t use the lightest Cuben Fiber available because we found it wasn’t sufficiently durable. We strive to make incredibly lightweight shelters and backpacks, but durability is just as important to us. We want your packs to last. Have any questions about Cuben Fiber? Post them on Twitter or Facebook, or email them to [email= info@hyperlitemountaingear.com]info@hyperlitemountaingear.com.[/email] We’ll be publishing more in-depth articles on the latest fabric we’re using, Dyneema, in a future blog post.