Boat Building Techniques

Hybrid construction could mean any method of building a boat which combines two different building techniques. In the case of kayaks it typically means building the hull using stitch and glue methods and the deck using strip building techniques. This offers the ability to quickly put together a hull using plywood, while getting the beauty of a strip-built deck.

This method of building boats use pre-cut plywood panels that are "stitched" together along their joints and then glued. The shape of the boat is determined by the shape of the panels. The 2 dimensional flat panels are bent when they are stitched along their curved edges to the adjoining panel. The shape of the curve between the adjoining panels determines the 3 dimensional shape of the finished boat. Stitch and glue boats can be build without forms although forms can help assure that the desired shape is acheived.

Strip building is the craft of turning a pile of thin strips of wood into a high-performance, durable boat. It is a great way to make a boat. It produces beautiful results that are also lightweight and strong. It may not be the quickest method to make a boat, but the individual steps are really not hard. It is a matter of shaping relatively small pieces of wood so they interlock tightly. The goal is to cover the boat with wood, and this simple idea permits a lot of room for creativity. Below are some pages that will describe and show some of what can be done

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.

Strips

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.

Because stitch-and-glue boat construction uses a relatively small number of wood pieces a boat can be build in relatively short order. Because plywood is inherently quite strong for its weight the resulting boat is quite tough and lightweight with a minimum of additional reinforcement.

While the technique quickly produces a boat, that does not imply that it is necessarily easier than strip-building. The shape of a stitch-and-glue boat is largely determined by the shapes of the plywood panels. If the panels are not accurately cut, the resulting boat may be quite badly distorted.

This makes stitch and glue designs very well suited for kits.

One of the biggest benefits to building a small boat with narrow strips is how accessible it is. While it looks intimidating, taking a bundle of small strips and wrapping them around a set of forms really is a matter of patience and not one of specialized skills. The tool requirement is minimal and the technique is very tolerant of mistakes. If you fail to make perfect joints between strips, the epoxy and fiberglass will fill them in and seal the mistakes.

If you are looking for a way to mass-produce wooden boats, strip-building is probably not the best choice. It is a time consuming method. More traditional methods of boat building tend to be quicker when performed by experience craftsmen, but that speed and ability to build a usable boat is largely dependent on the skill of the builder. The strength and water-tight integrity of the finished traditionally-built vessel is a result of the ability of the builder to make tight and sound joints. This takes skill and practice.

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.

"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.

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

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.