Outdoor enthusiast Tim Evans wanted a folding kayak but couldn’t find any that were up to his expectations. He decided to take matters in his own hands and started experimenting using a frame of aluminum and carbon fiber tubes and a Dyneema® Flexible Composite skin.
TE: My name is Tim Evans. I'm an engineer and former software developer from Vancouver, BC. I sold my share in the software business and now devote myself to other interests, such as building things and testing them in the outdoors.
TE: There are basically two types of kayak: hard shell and folding. I had done a bit of packrafting, which involves paddling whitewater rivers in small inflatable boats, and it was a lot of fun. But I wanted to expand my horizons to include flat water, where a kayak is a better tool for the job. I am also a fanatic about light weight. I just hate carrying a bunch of heavy stuff around. Folding kayaks have a fabric skin and an internal frame, and the parts can be carried in a backpack and assembled for paddling. They are often lighter than the rigid type, but portability was also important to me. I want to carry my boats all over the place, so a boat that is light and can be packed up, is a must. The lightest folding kayaks on the market are about 20 pounds. I was used to a 5 pound packraft, so this seemed pretty heavy to me. I wanted something closer to 10 pounds. To achieve this I would have to replace all the conventional materials used for the skin and frame with the lightest materials available.
TE: I was familiar with Cubic Tech materials, now Dyneema® Flexible Composites, from my online research into super light tents. Back then I obtained material from Cubic Tech and made a few of my own tents. I also got a sample book that included the 3 oz hybrid Dyneema® composite and Polyester material and figured that would make a super light, super strong folding kayak skin.
TE: Both my kayak projects so far have been experiments, in both design and use of materials, so to be honest I had modest expectations. However, the results have been fantastic. I have used both the polyester hybrid and the newer weldable material and both produced incredibly light, strong skins. To put the weight saving in perspective, the Dyneema® materials I'm using are only about 20% of the weight of the conventional materials used for most folding kayak skins. Combined with more modest weight reductions in the structural components, allowed me to cut the weight of the finished boat to roughly half that of the lightest commercial folding kayak of comparible length. The seams are all taped and have held perfectly, with no peeling or leaks. Abrasion is a concern, so I have to be careful to not drag the boats over rough surfaces like sand, and I try to keep away from the obvious hazards like rocks and floating logs. One small problem I had with the 17 footer was having it blown away on a windy beach. The thing is so light. I recently used the 10 pound 14 footer for a 100-mile paddle on the Rideau Canal in Ontario. I had a few aches and pains, but the kayak came away without a scratch.
TE: To create the design, I use Blender modeling software to create a 3D mesh, which represents the surface of the kayak hull. I use this to create patterns, which are traced over the Dyneema® composite fabric and then cut out. The final step is to tape the pieces together with 1" (25 mm) overlapping seams. I picked up some of the taping techniques online and developed some myself. Building the cockpit coamings and folding the material around the stems is a challenge that required coming up with some new methods. The only tools I needed were a good pair of scissors and some drafting tools like a straight edge, ruler and square. And since there is no need for any special equipment, or even a workshop, any bit of floor space will do. Both tents and kayaks also require rigid elements. For these elements, I use mostly carbon fiber tube. I designed some 3D printed parts I had locally made for joining tubes of different diameters together, or for joining tubes at different angles.
TE: Great question! In addition to the two kayaks, I have had four tents made with Dyneema® composite materials and am starting on a fifth. I have a rain poncho and I made some nifty little shoe covers to keep my feet dry on long walks across Europe. I've made stuff sacks and pack liners and I have a custom made lumbar pack in nylon that I'm thinking of redoing with the Dyneema® material. I've also experimented with a rain jacket, which at 75 grams must be about the lightest waterproof jacket possible. And I had some inflatable tubes made for one of the kayaks using the weldable material, but this is still a work in progress. Pretty much anything currently made with nylon or polyester could be made lighter and stronger with Dyneema® composite materials.
TE: I am currently working on both a new kayak and a new tent. I love to continuously refine my design ideas. With the 3D design, patterning and taping techniques, I have everything I need to realize a new idea while it's still fresh.