The most accessible techniques for do-it-yourself boat builders involves using wood. It is possible for someone who wants a Fiber Reinforced Plastic (FRP) kayak for example a fiberglass or Kevlar kayak to make one at home, but you will first have to go through most of the steps of building a wooden boat, so it is time consuming to build your first.
Wood can be worked with commonly available tools, is readily available in most areas and is structurally one of the best boat building materials available. Not because it floats, but because it is lightweight and very strong for it weight. Read more about the process below:
"Strip-Building" is the art of bending many, small, thin strips of wood around forms to create a boat shape. The wood is covered with fiberglass cloth and epoxy resin then removed from the forms and the inside is fiberglassed. This method allows a lot of design freedom because just about any shape may be produced. The results are very strong and stiff because of the composite construction with wood surrounded by fiberglass and sealed in epoxy. By varying the thickness of the wood and the amount of fiberglass applied the boat can be supremely light or extremely tough.
The fiberglass cloth becomes absolutely transparent when soaked with epoxy, so the result look like wood while having the low maintenance and durability of a fiberglass boat.
"Stitch and Glue" refers to "stitching" together panels of plywood with wire and then gluing the joints. A stitch and glue boat uses carefully cut panels of thin plywood which when joined together bend into the desired 3 dimensional shape. It is the geometry of how the panels must bend to create a tight joint that defines the shape of the boat.
This method of building goes together quickly because there are relatively few parts that must be assembled, however because the panels of plywood are relatively wide there is typically a hard angle or chine between the panels. This somewhat limits the variety of shapes possible, but does not detract from the performance of a well designed boat.
Like strip-built boats, the plywood is covered with fiberglass cloth on the inside and outside. The fiberglass provides significant strength and durability while letting the beauty of the wood shine through. The result is a lightweight and strong boat that requires very little maintenance.
Building a kayak using either the strip-built or stitch-and-glue method is within the means of most people who want to do it. Neither method is particularly difficult for anyone who is willing to take the time required. Many first time builders who have never done anything remotely like a constructing a boat have produced beautiful boats they are justifiably proud of. Wanting to do it is the most important prerequisite.
"Ease" can be broken down into at least two factors: time and skill required. A strip-built boat will take more time, a similar design of a stitch-and-glue boat will require finer skills to get right. The differences are mostly in the woodworking parts of the projects. After the woodwork is done, the fiberglassing and finish work is pretty much the same. Because a "stripper" requires individually fitting many narrow strips together, you spend a lot of time doing woodworking. Once finished with the stripping, you must sand everything smooth. Neither the stripping nor the sanding are particularly hard. While a "poor" job of stripping may look a little ragged, but even if you end up with gaps between the strips, the fiberglass and epoxy will seal all but the biggest mistakes and the finished boat will work very well.
A stitch and glue boat depends on the accuracy of how you cut out the panels of plywood in order to get the desired shape. Small errors in cutting the shape of a panel can result in weird boat shapes that may effect performance. However, since there are not that many panels to cut it does not take long to do the work and then there is less sanding involved.
If you buy a kit for either type of boat, you will save some time. However, with a stitch and glue boat, the work that is pre-done in the kit will have a lot of impact on the project. The pre-cut panels virtually eliminate errors in the panel shape and put the builder beyond most of the woodworking. A strip kit includes the forms and a bundle of strips. The builder still needs to do the individual fitting of the pieces, so most of the woodworking is still part of the project.
In conclusion, a stitch and glue boat is quicker, and with kit there is less skill required. If you are building from scratch strip-built boat is still going to take longer, but the work is not hard and mistakes are less critical.
The amount of time you take to build a small boat will depend on you previous experience, willingness to push forward, and your attitude. It is possible to pump out in 60 hours, or if you are being a perfectionist, you may end up putting 400 hours into it before you christen the finished boat. As mentioned in the previous page a stitch-and-glue boat will generally go together faster than a strip-built boat. Depending on the design, it is usually about half the time for a stitch and glue design vs a stripper.
I teach a kayak building class where in one week first-time builders create a nearly finished stitch and glue kayak from a kit. This is about 50 hours of work, with another 10 hours required at home. So in controlled and supervised conditions, the project can go quite quickly, but at home, on your own, you should figure on 100 to 120 hours.
A stripper can be banged out that quickly as well, but inexperienced builds should count on 200 to 250 hours. Since there are a lot more possibilities for individual expression on a stripper, some of the more compulsive builders may take longer yet.
A kit will save time: maybe 20 to 30 hours on a stitch and glue boat and about 30 to 50 hours on a strip-built design.
Most of the cost of building a kayak is labor, but doing the work is part of the fun so we won't count that here. Some people are really good at scrounging up materials or have especially good access to quality stuff cheap so we won't count that either, but is worth looking you around for unexpected sources of materials. For example old telephone poles were often cedar...
A strip-built kayak needs about 2 board feet of wood for each foot of boat length. Obviously longer boat and wider boats will need more and short boats will use less, but this lumber will generally cost $150 to $200. Forms for a stripper can be cut out of one sheet of inexpensive plywood or MDF and mounted on a simple 2x4 or plywood box beam for $50-$150.
A stitch and glue boat will typically use several sheets of high quality marine grade Occume plywood which can be quite expensive per sheet. A typical boat will take $180 to $250 worth of plywood.
Fiberglass and epoxy costs for either method is about the same. Figure on about 4 times the length of the boat in fiberglass for a typical kayak this runs about $150 to $200. A kayak will also use about 1.5 to 2 gallons of epoxy resin that can run from $100 to $200.
You will also need various sundries and expendable like sandpaper, brushes etc. which you can figure on paying around $100 for.
In summary:
Strip-Built |
Stitch and Glue |
|
| Wood | $150-200 |
$180-250 |
| Forms | $50-150 |
|
| Fiberglass | $150 - 200 |
|
| Epoxy | $100-200 |
|
| Sundries | $100 |
|
| Total | $450-850 |
$530-750 |
A stitch and glue boat will typically use three or four sheets of 4mm Occume marine plywood. With careful cutting you may be able to be more efficient.
For a strip-built kayak a good rule of thumb is 2 board feet of western red cedar or other softwood for each foot of boat length. A board foot is a volume of wood 12" long x 12" wide by a nominal 1" thickness. Most wood you will buy is planed down to 3/4" thick or even 11/16" for some cedar and redwood.
To get a little bit more specific it takes just under 18 strips to cover a 12 inch wide area. In other words to completely cover one square foot of surface area on a boat you will need 18 linear feet of strips. If you are looking at a design with a surface area of 50 square feet you will need approximately 900 linear feet of strips. This does not leave much room for errors so you will want to include some extra.
You can typically get three 1/4" thick strips out of each inch of board width for a yield of 36 linear feet of strips per board foot. This works out to 1/2 a board foot of lumber per square foot of boat surface area. So for 50 square feet of surface area you would need a minimum of 25 board feet of lumber.
Notice that the surface area of a boat varies widely for boats of the same length; the Petrel has a surface area of 46 sq ft and the Great Auk is 59 sq ft. The rule of thumb would suggest 34 board feet where the Petrel only needs 23, but the Great Auk needs almost 30, so the rule generally over estimates, but you will probably happier to have too much wood instead of too little. Don't try to get exactly the right amount forcing you to use tiny scraps to finish covering the boat.
You will also want a small amount of hardwood to finish up the boat. The coaming lip can be made by cutting up scrap strips into thin laminations, but you may want some nice hardwood such as ash, cherry or mahogany. Outer stems can also be constructed of hardwood. One board at least 36" long x 6" wide should provide you enough for most purposes.
To build a striper from scratch you the minimum tools needed:
Table Saw or Band Saw, (Not required with the kits)
Jig Saw
Block Plane,
Thin Kerf Hand Saw,
Jack Knife,
Sanding Blocks.
A selection of clamps