After reviewing your comments and other forum posts it is clear the biggest challenge for backcountry hunting packs is the wide range of weight they must be able to carry. For backpack hunts, up to 60 pounds going in and up to to 100 pounds coming out. If you hunt any distance from the truck daypacks need to be able to carry a boned out animal or quarter. This big weight variation has been a tough problem for most manufactures to solve. The best load carrying packs are heavy, stiff and cumbersome to hunt in all day and daypacks do not have the frame and suspension to handle a heavy load.
We need a lightweight pack that solves this problem; a pack that is comfortable to hunt in all day and is designed with a frame and suspension to carry a heavy load.
I began the development process by researching and reviewing existing pack frame materials, including aluminum, steel and plastics. My research concluded these materials could be designed to be either stiff for carrying weight or flexible for comfort, but are limiting in designing a frame that can do both and remain lightweight. My research also made it clear we need a frame with vertical stability and horizontal flexibility. Vertical stability supports heavy load carrying and horizontal flexibility creates a comfortable all day ride.
Fortunately, these conclusions forced me to research alternative materials, which lead me to Carbon Fiber.
Carbon Fiber consists of extremely thin fibers about 0.005–0.010 mm in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are aligned parallel to the long axis of the fiber. The crystal alignment makes the fiber very strong for its size. Several thousand carbon fibers are twisted together to form a yarn, which may be used by it self or woven into a fabric. Carbon fiber has many different weave patterns and can be combined with a plastic resin to create a high strength-to-weight ratio material. The density of carbon fiber is considerably lower than the density of steel, making it ideal for applications requiring low weight. The properties of carbon fiber such as high tensile strength, low weight, and low thermal expansion make it very popular in aerospace, military and motorsports.
For the past year I have worked with an industrial design group that specializes in carbon fiber to developed the world’s first Carbon Fiber backpack frame, which KUIU now has a patent pending. The KUIU Icon Carbon Fiber frame weighs just 13 ounces, is only 1/4″ thick, has stiffness vertically to carry heavy loads and is flexible horizontally for an incredibly comfortable ride. This ultralight dynamic structure can only be accomplished by using carbon fiber. Light, strong, stiff & flexible.
The Icon frame is made in a mold, which allows us to shape it to the spine for a better fitting pack. At 1/4 inch thick, your load rides right against your back and angles forward when you engage the loadlifters for a perfectly balanced pack. We inset a pivot waist belt attachment and shoulder harness track system into the frame. The pivoting waist belt allows the pack to move with your body allowing for a more comfortable ride. The individual shoulder adjustment makes it easy to properly fit of a wide range of body types, which is critical in carrying heavy loads.
The most important design feature of the Icon frame are the stays that run vertically on the outside of the frame. When under weight these stays de-couple the weight from your shoulders and hipbones and distributes it to your lower back, upper back and upper chest. This allows for a ride that is incredibly comfortable and perfectly balanced. No more sore shoulders and hips. When unloaded these stays have horizontal flexibility that allows the frame to move with your body creating an incredibly comfortable daypack.
The Icon Carbon Fiber frame is the foundation of two new pack designs, an estimated 2500ci and 5500ci. These packs are the lightest in their class, have an advanced suspension system, new lightweight fabric, designed for hunting and will out perform any pack made to date. I will cover both packs and suspension in up coming posts. These packs will be available late Spring 2011.
I look forward to your thoughts and feedback and please let me know if you have any questions.