Welcome to our new Building a Kayak website. We won’t claim to have all the answers, but we have had some success and since we’ve already bored all our friends with the whole kayak odyssey, we figured it was time to branch out to a new audience.
Over time we’ll fill in the site with what we know about kayak building, share what we learned through the process, and even offer some untested opinions on what we’d do next time.

One of our goals here at Building a Kayak is to not just spout out our own ideas, but also to help you find links to useful resources elsewhere on the web. So with that in mind, I thought this teleseminar from Glen-L Marine might be useful to others. Glen-L has a huge repository of boat plans, ranging from the 8′ Tiny Titan to a 49′ Klondike trawler yacht. While not one of the more common sources of kayak plans, they do offer a few including the Kidyak, the Can-Yak, the solo Sea Kayak and the tandem Sea Kayak Two.

I have subscribed to Glen-L’s newsletter for a number of years, but only recently have they started offering teleseminars. In this particular teleseminar, Gayle Brantuk from Glen-L is interviewing Kern Hendricks who is a chemical engineer and the owner of System Three resins. I figured that if you were looking for input on how best to use your epoxy, you probably can’t get a better source than going direct to the owner of one of the most common epoxies out there. Here is the link to the “System Three Teleseminar with Kern Hendricks”.

The New Kayak Shop by Chris Kulczycki is a standard resource for anyone who is thinking about building a stitch-and-glue plywood kayak. Chris is the founder of Chesapeake Light Craft and The New Kayak Shop is the updated version of his original The Kayak Shop.

This book covers the full sequence of building a plywood stitch-and-glue kayak from design considerations through to the outfitting details. Included in the book are plans for the Chesapeake 16 and West River 180 sea kayaks, along with the Severn flatwater kayak.

There are a couple of things to keep in mind as you read the book. When you are working through Chapter Five: The Plans, you will probably notice that no offsets or measurements are provided for the plywood deck sections. Don’t worry, this is on purpose. Over the years, Chris has found that tracing the shape of the deck sections from the kayak once you have the hull built works out best. The next thing to remember is that with any kayak project book, you really do need to read it pretty much cover to cover. I spent a fair bit of time while reading wondering if plywood stitch and glue construction really could be as easy as Chris makes it out to be. By the end of the book I’m convinced that it’s all there.

To quote from Chapter One: The Wooden Kayak - “The hardest part of building your own kayak is getting started.” So what are you waiting for?

Kayaks come in a wide variety of lengths, widths, and shapes. These differences really do affect how the kayak will handle and respond on the water. Understanding the terms used to describe the kayak specs will both help you compare different kayak designs and help you choose a kayak that will fit your paddling activities.

With apologies for my artistic abilities (or lack thereof), I’ll try introduce some of the key terms that you will come across when looking at kayak designs.

Length Overall (”LOA”) vs. Waterline Length (”LWL”)

An easy starting point is to look at the difference between the Length Overall and the Waterline Length (or Length Water Line) as it applies to a kayak. As shown in the illustration below, the Length Overall is simply the maximum length of the kayak. This is the measurement that you are going to care most about when deciding whether this kayak will fit in your garage or workshop for building or storage. The Waterline Length is then the length of the kayak hull that should be measured flush with the water level when the kayak is carrying it’s designed load.

This introduces the term “design waterline”. When a kayak, or any other boat, is designed, one of the goals that the designer takes into consideration is the weight that the kayak is expected to hold. If the kayak is under loaded, it will sit higher in the water. If the kayak is overloaded it will sit lower in the water.

Coming back to length, length can be important because it is related to the theoretical maximum speed of the kayak. I say theoretical both because there is a theoretical limit to hull speed, but more importantly because most of us don’t paddle anywhere near the top speed of our kayaks for more than a minute or two at a time. Nonetheless, a longer kayak will tend to be faster that a shorter kayak, especially if they are similar in other aspects.

Length can also be related to tracking - how easy it is to keep the kayak moving in a straight line. A longer kayak will track well, meaning that it will tend to keep moving straight without require a lot of steering or correction strokes. In contrast a short kayak will turn more easily which is a good thing for a whitewater kayak which needs to turn quickly, but is less desirable in a lake tripping or sea kayak where you want to go straight for a relatively long time.

Maximum Beam vs. Waterline Beam

Beam is really just another word for the width of a boat or kayak. Since most kayaks tend to flare out from the waterline to the gunwale, the maximum beam is normally going to be wider than the waterline beam. Beam is relevant to both speed and stability of your kayak. A kayak with a narrow beam will tend to be faster than an equal length kayak with a wider beam. On the other hand, the wider kayak will provide more stability from side to side. This stability can be useful for a new kayaker and is also something that folks will look for in a fishing kayak.

Illustration of the meaning of maximum beam and waterline beam for a kayak.

Rocker

Rocker is a measure of how much the keel of kayak curves up from the middle of the hull to the bow or stern. A bigger rocker ‘frees up’ the bow or stern to let the kayak turn more easily. Understanding the effect of rocker is important when comparing 2 kayaks with the same length. The kayak with the greater degree of water will turn more easily, with less effort, but won’t track quite as well.  

Illustration of rocker on a kayak, including the difference in rocker between a sea kayak and a whitewater kayak

Now, while I haven’t illustrated it, keep in mind that as you tilt a kayak on it’s side, you will change the portion of the hull that is in the water and as a result the effective rocker of the hull. This helps to explain why a long sea kayak with a relatively small rocker can carve such beautiful turns when tilted into the turn.

Hull Shapes

The final characteristic that we’ll look at in this article is hull shape. The illustration below compares a relatively flat bottomed hull to a round or arched bottom and to a “vee” bottom hull. The cross section shape of the hull relates to the primary and secondary stability of the hull. For a detailed description of primary stability and secondary stability you can take a look at KayakWiki. In simple terms, primary stability defines how tippy a boat feels when you first get in to it  and secondary stability defines how that tippiness changes as the boat tilts to one side or the other. With a flat bottomed hull, you have a relatively high initial or primary stability which means that it takes a fair bit of effort to start tipping the kayak. However, once you have the kayak starting to tip, it will have a relatively low secondary stability and want to quickly go right over on it’s side. In contrast, a rounded or arched hull will have a lower initial stability and will happily start to lean to the side, but since the hull shape is very similar whether the kayak is straight upright or tilted, the rounded hull will have a higher secondary stability. Looking at the “vee” shaped hull, I have drawn a relatively shallow “vee”. This shape will likely be similar in stability to the rounded or arched hull, but the “vee” can provide more of a keel to help the kayak resist being blown sideways by the wind. If the “vee” was a sharper angle, then it would have lower primary stability but would firm up with a relatively high secondary stability as the kayak leans onto the relatively flat sides of the hull.

Illustration of flat bottomed, round or arched, and “vee” shaped hull cross sections of a kayak.

There are a number of choices that go into picking a kayak design. Some of the factors that you will have to consider include:

1. What building technique to use?
2. What type of kayak to build?
3. What shape, length, and width do you want?
4. How big a kayak you need?
5. Which kayak looks best?

But one thing we haven’t talked about yet is where you’re going to keep it when you finish building it. This last point is worth a bit of thought. If you’re like us, you’ll probably take over the garage to be your kayak building shop, or maybe you’ll build it outdoors like I did with my first canoe.

If you have the option, then storing your new kayak indoors is the best choice. While all of the building methods will give you a solid, durable kayak, even the commercially built kayaks are sensitive to ultraviolet (UV) light. Keeping your kayak indoors when you aren’t using it can go a long ways toward extending the life of your kayak.

So before you order those plans & forms for that 19′ sea kayak, run on out to the garage or the storage shed and measure it one more time to make sure it will fit at the end of the day.

Ok, so you’ve decided to go ahead and build a kayak, you’ve done some searching, you’ve looked at different kayak models and styles, and you noticed that there’s more than one way to build your own kayak. So, which kayak building technique is the best?

Well, I can’t tell you which building technique is best for you, but I can help explain the differences.  The most common techniques for building your own kayak are:

• Stitch and Glue
• Wood Strip
• Skin-on-Frame

Stitch and Glue

Chesapeake Light Craft is one premier source of both plans and kits for stitch and glue kayaks. With stitch and glue construction you start with relatively large, flat panels of plywood that are temporarily “stitched” together  before being permanently glued together using fibreglass tape and epoxy. Just as if you were sewing together a bag, the shape of the individual panels combines to create the finished shape.

A few advantages of the stitch and glue approach are

1. It requires less initial set up than a wood strip or skin-on-frame kayak.
2. The marine plywood used is extremely hard, durable and tough making you finished kayak very hardy.

The biggest drawback to a stitch and glue kayak seems to be that the plywood panels can only twist in one direction at a time. This means that the kayak shapes that can be built with this method are more limited than with a wood strip or skin-on-frame method. Of course you can always use more, narrower panels of plywood to get a more complex shape and this done. However, the more panels you add, the more work you create and the closer you get to a wood strip construction style.

Wood Strip

Good sources of wood strip kayak plans and building instructions include Bear Mountain Boats and Guillemot Kayaks. With wood strip construction you start by setting up a strong back - a long, straight building platform - with station molds set up at regular intervals. The wood strips, usually of cedar, are temporarily fastened against the molds while you construct the hull and deck of the kayak. Each strip is glued to the strips beside it. The temporary fastening to the station molds can be done using staples, clamps, straps, or a combination of all three. Once the hull or deck shape is completed, a full length and width layer of fibreglass is attached using clear epoxy to both the inside and outside of the hull or deck.

Some of the benefits of wood strip construction include:

1. Being able to build a more complex or even just a smoother hull shape than you can with a stitch and glue method.
2. The durablility of the wood-fibreglass sandwich. While the cedar is a lot softer than the plywood in a stitch and glue construction, the fibreglass shell gives a lot of protection.
3. The option of creating beautiful patterns not only with the layout of the strips, but also by including contrasting woods.

Most of my experience in boat building is with cedar strip construction and I really do like this approach. Nonetheless, I can see a few drawbacks. Setting up the strongback properly isn’t trivial. This is a detailed part of the job and your accuracy in getting the strong back and station molds set up straight & square is crucial to the process. Compared the stitch and glue, wood strip construction may take a bit more woodworking skill, but more likely it really just looks a little more intimidating up front.

Skin-on-Frame

Skin-on-frame is undoubtedly the most traditional method for building a kayak. One nice write up on the building process is Terry Reed’s site showing his construction of a Yostwerks Sea Tour 15-R. With this method a series of cross sections or stations are fastened together with longitudinal stringers to create a frame. The frame is then covered with fabric and waterproofed. While a historically authentic covering would be seal skin, more recent options have included canvas and nylon.

Some of the benefits of a skin on frame kayak can include:

1. The traditional feel of a skin on frame kayak. This just might be the closest you can come to the ‘real thing’
2. The minimal use of wood. While you still need full length pieces for the longitudinal stringers, and I would still recommend a marine plywood if you are using plywood for the stations, you aren’t going to be using the very long, very clear cedar required for strips in a wood strip kayak, or the marine plywood made from tropical hardwoods in a stitch-and-glue kayak.
3. You still get the ability to create complex hull shapes, just as you would with a wood strip kayak.

The biggest disadvantages I see to a skin on frame kayak are durability and rigidity. The skin itself is going to be much less resistant to a puncture than either a stitch and glue or wood strip/fibreglass kayak will be. At the same time, the lengthwise strength of the kayak to maintain it’s shape is entirely provided by the stringers. If you crack or break a stringer, maybe even just by dropping the kayak awkwardly when putting it on a car some day, you could have a serious repair job.

Considering that you are reading a website about building kayaks, you likely already have your own definition of what a kayak is. However, just to make sure that you and I are on the same page, I figured it wouldn’t hurt to write out a working definition. So, pulling out our old “Random House College Dictionary” (©1980) I get:

1. an Eskimo hunting craft with a skin cover on a light framework, made watertight by a flexible closure around the waist of the occupant.

2. a small boat resembling this, made commercially, for use in sports

Well, that definition is a bit dated now, so I went and checked a newer universal source of knowledge:  Wikipedia or rather Wiktionary and got this definition:

1. a type of small boat, powered by the occupant or occupants using a double bladed paddle in a sitting position

Neither  of those definitions quite fit for me. Growing up, the definition of a kayak was always made relative to a canoe and the distinction was easy. A canoe was open on top while a kayak had a deck, you kneeled in a canoe but you sat in a kayak, and you used a single bladed paddle in a canoe and a double bladed paddle in a kayak.

But then I found out that some of the oldest canoe designs were decked like a Rob Roy or were built for sitting instead of kneeling like a Wee Lassie.  To make matters worse, many folks would paddle these canoes using a double bladed paddle! Aaarrggghhhh!

So where does that leave me today? Well, I’ll take the Wiktionary definition but I’ll add that, for me, a kayak is a boat with a deck that you sit inside. You might not always have a spray skirt to be “watertight”, but you will sit down, in the kayak.

Now if you happen to like “sit-on-top” kayaks, then feel free to keep on calling them kayaks. As far as I’m concerned, any boat that gets you out on the water is a good one.  And if you ever want to debate the definition, I’ll be happy to let you make your case over a beer or two.