One Ocean Kayaks home The Wood Kayak

What to expect from a wooden sea kayak clad in epoxy and fiberglass? This page may help to answer most of your 'Frequently Asked Questions' about wooden kayak construction.

   Easy Construction - Can I build a wood strip kayak like this?
   Lightweight Monocoque Shell
   Strength & Stiffness
   Inexpensive
   Beauty of Wood
   Fast Building Time
   Uncompromised Hull Form and Shape
   Impact resistance
   Maintenance
Wooden Sea Kayak Designs
Wood strip Kayak Shop
Wooden Sea Kayak Gallery
 

 

Mechanical principles of Composite Sandwich Cores. This page casts some light on the nitty-gritty technical stuff.



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Easy Construction

You may wonder, can I even build a kayak like this? If you like a little challenge, you certainly can! There are thousands of wood strip kayaks around the world, many made by people for whom this was their first building project of any kind. The vast majority of builders are the 'weekend warrior' types who relax by this artistic endeavor.
It is almost hard to believe but many paddlers who build wooden kayaks will also go to any length to find a place to do it.
Wood strip kayaks are being built right now by amateur builders in garages, sheds, lofts, basements, hallways, attics and of course in livingrooms and bedrooms! Few people even asked me how to build their kayak in TWO sections so that it would fit in their space. It seems like the ingenuity and persistence of the wood strip builder just knows no limits. Looking at the fruits of their labor, it is easy to understand why; The muse of creativity will not be silenced.

The simplicity of kayak building starts with the full size plans. You will immediately appreciate the speed with which you can put together the whole set of stations (forms). Furthermore, with the exception of spacing the stations on a "spine"(strongback), you need not MEASURE anything! The entire mold is designed for visual alignment using only a level. One sheet of plywood and particleboard is all it takes to make a precise form.

Using strips to build the body of the kayak is the best feature by far. So what if you break a strip... pull out a few staples and you are in the game again. Made a big gap? When it gets filled, glassed, and varnished you will have to search to find it. Stripping will simply tolerate errors that would be unacceptable in most other building methods.

Stapling pliable strips of cedar over the gentle curves of the forms, sanding foot by foot or cutting hatches a bit at a time gives you great control over the quality and pace of the project. You can build as fast or slow as you want.

Fiberglassing IS easy, too. Poor quality of resins from years past has generated too many horror stories that make novice builders unnecessarily apprehensive. These stories could be generally summarized as: "Wrong resin and wrong instructions for the wrong job under wrong conditions".

The epoxies used for clearcoating wood are of the best quality and should not be confused with the smelly "esters" or the 5min epoxy tube in a hardware store. With the slow hardeners, you will have the hull almost completely coated before you need to squeegee, and it will take a few more hours before everything sets.

Over the years I have worked with many resins but the ones I use now, both the MAS and West System epoxies have excellent properties that makes them quite foolproof. If you want to find out more about epoxies check out the Epoxy Test page to see how six popular epoxy types compare in UV degradation and other qualities.


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Lightweight Shell

Light weight is the forte of all core structures used in boatbuilding and wood strip kayaks are no exception. They belong to a class called Monocoque Shells. (From French- Mono: single and Coque: shell)
Monocoque shells are structures where the walls support themselves including all other loads and stresses. They don't need any internal reinforcement such as ribs, stiffeners etc. This eliminates a lot of superfluous weight. Even smaller craft such as single skin fiberglass kayaks are monocoque but as their size increases such as in expedition or double kayaks, the skin needs to be built thicker to maintain sufficient stiffness. The price of that is exponentially increasing weight.

This is where wood strip sea kayaks really shine! The composite core has sufficient reserve stiffness and strength that even much longer and larger Expedition kayaks can stay light.
All this means is that everything you do with the kayak is simplified.
Loading and unloading kayaks, for example, can be quite a chore but my even my wife can put a strip kayak on a car roof with ease. Low weight also means easier paddling, maneuvering and covering larger distance with less effort.

Take an 18ft single skin fiberglass kayak (heavyweight), for example. It will weigh about 60 to 64lb and its kevlar counterpart can shave this by about 6lb. Compare this to a solid red cedar kayak of the same size. Its weight will span from 39 to 50lb max. depending mostly on the fiberglass lay-up.
It gets better still; A 21ft fiberglass double will be around 85 to 95lb but the same double "stripper" such as the Cape Ann II will be no more than 75lb! This includes hardware, rudder and everything else attached. So, while the commercial builders struggle to shave 2-3lb with the latest vacuum bagging techniques, with a 'stripper', you get an immediate 10-15lb weight saving bonus!

Let me say a word of caution about exotic wood. If you want the lightest possible kayak, limit your inlays and decorations to Cedar and low density wood. Careful use of hardwood is fine but don't be surprised that one 18ft strip of beautiful Bubinga may weigh as much as 1lb (ugh!).

The most suitable wood in terms of weight and workability:
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Strength & Stiffness

The mechanical properties of the sandwich core are the main source of strength but there is an additional bonus that comes with wood strip kayaks.
The cedar strips forming the kayak are inherently stiff and strong themselves, making the shell far stronger than if it was built using a different core. Of course, all other variables remaining the same (thickness, lay-up etc.). No other lightweight core material I know of (besides plywood) has the same self supporting qualities. You will notice this unmistakably, as soon as the kayak mold is completely stripped. The 1/4" shell stays rigid even in the spans between the stations of the form. There is no flex when you sand or plane.

One enormous advantage of a rounded wood strip kayak is its 'compound' shape. Ever tried to 'flex' an egg shell of an unbroken egg? It is enormously stiff because of its compound shape, not the thickness of the shell. Once you break the egg, the shell is as fragile as glass. This lesson of natural design was quickly learned by medieval architects who realized that the only way to build large cathedrals was with 'compound' domes not flat roofs. The examples of this principle are everywhere around us and the same applies exactly to the smooth round surfaces of wood strip kayaks.
A flat plate such as a plywood panel will always be less stiff than a compound shell made of the SAME material and thickness.

Because of this structural advantage, you will be very surprised how solid the whole kayak feels when it plunges into deep wave troughs - a massive slam without a shudder in the hull. When you are out there, far away from the shore and you get in a really 'hot water' you will thank yourself that you are riding a solid wood core kayak.
 
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Inexpensive

One nice thing about wood strip construction is that the entire sea kayak can be built inexpensively with a few specific but basic tools.

  •  jigsaw
  •  electric stapler
  •  drill
  •  finish sander
  •  level
  •  orbital sander
  •  beltsander (optional)
  •  plane
  •  Japanese pull saw

If you have a table saw and a router, making your own strips will make the project cheaper yet. You can rent these tools but if you don't want to go to this length, you can order quality wood strips commercially.
So that is it. As far as boatbuilding is concerned this is as minimalist as one can be.
If you would like to see all the tools I use, visit the Kayak Shop.

The actual cost of wood for an 18ft kayak such as the Cape Ann is $144 and it assumes you make your own strips from planks ($3 / ft^2). About 3 planks (3/4"x10"x16') are needed altogether. The rest of the materials, mainly fiberglass and epoxy adds another $400 to $600. Altogether, a top notch wood strip kayak comes to about the same price as a low-end polyethylene kayak.

For a more detailed account, see the Cost Estimate page for the Cape Ann Double. The Kayak Building Manual also gives a detailed account of materials and generally strives for the most cost effective ways of building.

Another way to look at this is that wood strips make for the cheapest core material bar none! You would be hard pressed to build a solid core kayak from a different material for less than 4 to 6 times the cost of cedar core.
And of course, a labor of love is FREE!



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Beauty of Wood

The character of wood grain and inlay under gleaming coats of varnish is hard to deny. I am not alone in believing that wood strip sea kayaks are the most beautiful craft of its kind.
This will become quite clear when drivers on the road give you 'thumbs up' and people on the beach stop in their tracks to inquire how you made such a beautiful thing.
You have been warned!

 

Metric / Standard unit converter
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Fast Building Time

Strip building is not the quickest way to build a kayak. The reason I say it is fast, because IT IS the fastest method in its category - that of potentially efficient hulls such as female molded shells or otherwise material unrestricted hullforms. If you require a faster building time, check out the stitch & glue Cirrus or the Cirrus Hybrid.

When I started designing kayaks, I often felt lured by other, quick built methods to get on the water as soon as possible. Yet, wanting to build fast high performance kayaks, wood stripping was the only way to go. I decided that a couple extra weeks were an easy sacrifice to paddle the best wooden sea kayaks for years to come.

You can finish a single in two months of weekends and afternoons with shop and tools ready but more realistically, it may take 2.5 to 3 months if this is your first project. For a double, four months is about right.

 
 

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Uncompromised Hull Form

I mean it when I say that this factor alone convinced me to go the "strip built" route. I have yet to stumble over an obstacle that prevents me from developing the kayak hullform exactly as I want!
I design kayaks to please the kayaker, not the material from which it's built.
Beautiful or classic as they may be, ribs poking through concave panels of fabric kayaks are not my idea of high performance hull form. Even multichine plywood kayaks cannot match the performance of smooth "stripper" shells.

Wood strip sea kayaks, like composite hulls, hold their shape through any conditions and the strip method imposes no restriction on hydrodynamic efficiency. Smooth hull just means that you will get faster where you want to go with much less effort.
It is a fact, that unlike ANY OTHER home built construction method, compound, concave or convex sections, and almost any radius of curvature are possible to achieve with wood strips. This is the ultimate hallmark of strip building.

From a naval architect's perspective, the freedom in design alone makes these home built kayaks a WINNER. From the paddler's perspective, the beauty of wood strip inlays, comfort, AND the performance on the water makes them a CHAMPION !

Click for more information about seaworthiness and how to choose a Sea Kayak.

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Impact Resistance

No matter what kayak type you have, there is always some compromise to deal with. Plastic kayaks weigh a ton and are slow, composite kayaks are expensive and are heavier than 'strippers', fabric kayaks rip and need very high maintenance, plywood kayaks do not have the aesthetics of strip kayaks and most do not have the optimal hull forms at that. Wood strip kayaks do have a weakness and that is that they are sensitive to impact.
Because of this you will not see too many wooden kayaks in white water competition.

The unique property that makes sandwich core extremely strong relative to its weight is also it's Achilles heel.
As the core relieves its skins from a lot of bending stresses as well as the need for self sustained stiffness, the skin needs to be only very thin. This makes it rather incompatible with sharp rocks. If you plan on doing white water or similar activity I recommend against any lightweight wooden or composite kayak. Instead, a polyethylene hull is the best in this respect.

The best way to improve your kayak's impact resistance is to add more external layers of fiberglass or special abrasion resistant fabrics in critical areas along the hull keel. It adds a pound but it works! Wooden kayaks are not furniture and should not be treated as such. Aside from impact resistance, they are some of the toughest craft to damage in normal use.
Alas, more attention to landing and launching technique will make your kayak live a happy, long life.


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Maintenance

If the maintenance work is a con, the results are a definite pro. If you use your kayak a lot, it is a good idea to wet sand the dulled varnish every three years or so and put on a new coat. Two afternoons is not such a terrible price to pay to give your kayak a "brand new" look.
More importantly, accumulated scratches also reduce the hull speed over time due to viscous (friction) drag and re-varnishing will allow your hull to regain all that has been lost.

Varnished surfaces, by the way, are the benchmark for the lowest Coefficient of friction (Cf) as far as hull surfaces go (Dust free, of course ). How is that for a bonus! No gel coat, poly plastic or fabric can ever be rejuvenated to a "day one" performance like your stripper kayak. If there was a definition of lasting value this could come very close.

As a note of interest, the Cf of worn polyethylene is up there, together with raw wood.


Want to know more?
Check out the Kayak Shop to see how these kayaks are built or click on the One Ocean Kayak Designs to see which one you would be like to paddle.




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Mail:
Vaclav Stejskal
10 Colonial Court apt. 73
Stoneham, MA. 02180
           USA
Tel:  781-481-9261

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Last page update: 29 October 2013