Building a Perfect Kayak: My Adventure in Kayak Design and Cedar Strip Building

I stood looking up at the kayak, a plastic Dagger Magellan, inside of our newest yet unopened store in the middle of Iowa. With the sunlight beaming through the sunroof and hitting the plastic of the kayak, which was standing on its end, I could see a small clear flaw. When the rep showed up, I pointed it out and he called to see if he could get a discount. When I mentioned that I was interested in purchasing it, he got an even better price for me – a price well below pro-deal. After he handed the phone over to me, a visa card number later and the boat was mine. That started my affair with kayaking. Used for a year, the Magellan served me well as we explored the lakes and rivers of Iowa, but almost the same day I bought a kayak, my buddy Steve Hauptli bought one also. Hauptli purchased a Dagger Apostle, and his boat had a few features that I liked that the Magellan didn’t have, so after a year I sold my kayak to a friend with the full intention of buying a fiberglass Dagger Meridian, but a few months after selling my kayak, my car blew up. One Corolla later and my kayak money was spent.

Over the next year, I built a canoe in my living room, bought a solo canoe, and didn’t look back at kayaking. I had rediscovered my roots that were formed on the backwaters of the Mississippi River in an old fiberglass canoe that needed constant repairs. Eventually, I found myself paddling my canoes with friends that kayaked, and they looked to be having so much fun rolling and playing that I wanted a kayak again. So, I built a skin-on-frame kayak, Greenland style. Then in three weeks time before a 560-mile paddle down the Mississippi River I translated that design into a plywood boat, and paddled that kayak down the Mississippi River. Over the course of those 15 days, I discovered and made choices about the type of kayak that I wanted to build next. As a boat builder, even in the middle of a building project, I’ve found I have the desire to start the next one.

So, over the winter, I started the design process, and in the spring sold my plywood kayak for cost of materials and nailed down my design based on the choices made on the Mississippi River Trip.

My Design Criteria for Building a Cedar Strip Kayak

My design criteria, which I formulated while paddling a less than ideal kayak for my purpose, could be simply summarized as a efficient, good tracking, mid-size capacity, kayak for touring, mainly along the Lake Superior coast. But I wanted to set in stone what I was looking for. I drew up a list:

1. A strong tracker.
2. When leaned, a good turner.
3. Mid-sized capacity for lightweight trips of 10 to 20 days or 280 to 300 pounds of displacement on fresh water. (I’m 190, 40 pounds for the kayak, and the rest for gear.)
4. A hull easy to paddle at touring speeds or about 4 knots of speed at 3.5 to 4 pounds of drag.
5. In the 17 or 18 foot range.
6. Under 22 inches wide.

Because I know how to use the boat design program, Hulls, I started work in that program using my last kayak as a starting point, but because I was thinking of building a kayak out of cedar strips, I added chines to smooth the flow of the lines away from flat panels to a nicely rounded design. Eventually, after pouring over old Sea Kayaker Magazines and examining kayaks that I like to paddle, like the Romany and the Chatham, I came up with a design that although not copies of those two boats, certainly echoes their design. To address my list of criteria I did the following:

1. Used only 1.5 inches of rocker measured at the point the stem becomes the keel in the front and .75 inches of rocker in the back. Narrowed the entry lines to form built in “skegs.” And made sure the Center of Lateral Area was slightly behind the Center of Buoyancy.
2. I made the center of the hull have more curve and volume, so that when leaned the ends could lift out of the water, and thusly deliver a slight short, but more rockered hull design for easy turning.
3. At 300 pounds, the boat drafts at 5 inches, which is on par with the Romany and Chatham. This puts the waterline close to the sheer line, but 2.5 inches away from the lowest spot on the deck, which is behind the cockpit. At 240, pounds of displacement, the kayak drafts at 4.4 inches, which adds some freeboard for my girlfriend should she want to use it for touring. This also turns out to be nice for day trips for me.
4. Although, I haven’t run the numbers in KAPER yet, I believe that they currently indicate that the hull will fall within this range at 250 pounds of displacement. The Prismatic Coefficient, which is an okay indicator of hull speed and efficiency, is .53 at 250 pounds and .54 at 300 pounds.
5. The final design ended up at 17 feet, because of the room in my shop, but, also, because it will work better for my girlfriend at this length, and will be easier to use in rough water near shore in rock gardens.
6. The final boat ended up at 21.25 to the outside of the hull when stripped.

Since this is only my second design, I still have a few doubts about my choices, but I’ve tried to study and learn and apply what I’ve learned as well as I can to the design. Still, these few points nag me:

1. Will this track too well and sacrifice my ability to turn, which is something that I enjoy doing when playing.
2. Will this allow me to turn fast enough?
3. Would I rather have it draft slightly shallower.
4. Should I crunch the numbers for KAPER?
5. I could squeeze 18 foot into my shop.
6. Should I have designed it to 23 inches for a more stable photo platform?
7. Would the design, which was designed for plywood, when changed to strip building keep the same characteristics?
8. And finally why not build a proven design like the One Ocean Expedition or the Orca Hyak, which both seem to fit the criteria that I’ve laid out, and they both seem to have that look I’m after. Especially, the Hyak.

Initial Design Work Over and Now the Choices

With the initial design work over, I had to make several choices before starting the project. The main one was plywood or cedar. And in the end, although, plywood has a lot going for it, I decided that the beauty of cedar strips is unmatched when it comes to building. Plus, I’d have much more flexibility in the patterns that I use on the deck, hull, and the inlays wouldn’t be wasted on an ugly plywood hull. I know that many people like the look, but I can’t stand the look of a plywood hull. I’m not sure why. So, my choice of cedar made, I had to somehow translate that design into cross sections that were rounded and fair to each other.

Finding a Solution in Software

When I originally designed this kayak, I started with it based on my last kayak, which was designed in Hulls. I completed a good amount of design work when I decided to see how it would look as a stripper. Because Hulls only outputs panels, I had a couple of choices. The first was to hand loft all the needed stations for the final boat. This seemed like a ton of work. The second was to download Bearboat and Kayak Foundry, which I did, but for some reason, I couldn’t figure out how to translate my design from Hulls into either of these two programs, and I just ended up frustrated. The third was to figure out how to get the Hulls file into a modeling program that would allow me to alter and fair the hull for cedar strip building.

To this end, I downloaded a program called Crossroads, which takes a WRL file outputted from Hulls, and exports it into any number of formats. At first, I turned to open source software and tried a number of programs, like Wings, but I found them lacking the features I needed. I had seen several wonderful kayak designs done in Rhino, but I didn’t want to buy that program just for one craft, so I turned to my sister, Becky, who is an architect. She recommended the program Sketch-Up 5 to me. It turned out that Sketch-Up offers a demo that is fully functional for 8 hours. Would 8 hours be enough for me to figure out the program and do the design work that I need to do? Only time would tell”¦