Boat building is a craft with tremendous tradition, and staggering depth. As such, it would be impossible to be comprehensive, even in a very long article. Here we’ll discuss the absolute basics.
Here are some of the basic structures that make up a boat (this picture is a side view, pardon my lack of artistry):
A- Sheer: The sheer is the horizontal line which represents what is basically the “top” of the boat. When you step into a boat, you are stepping over the sheer line. If water comes over your sheer line, you sink; or rather, you’ve sunk.
B- Transom: The rear of the boat. The transom goes from the aft-most point of the keel to the aft-most points of the sheer on either side. Some boats, “double-enders” have a stem on both sides, rather than a transom, so that they can go more easily in either direction.
C- Keel: The bottom of the boat, where the starboard and port sides come together. Incidentally, if you were “keel-hauled,” it meant that you were dragged along the bottom of the boat by a rope. This generally resulted in death by drowning, but was unpleasant regardless.
D- Stem: The stem is where the keel rises up to the transom. It creates a nice, low-drag front, so that the boat can cut through the water.
Starboard is the side of the boat which is on your right when you are facing forward.
Port is the side of the boat which is on your left when you are facing forward.
The stem is at the fore, or forward-most part of the boat.
The transom is at the aft, or rear-most part of the boat.
To begin building a boat, you construct frames. Frames run from the keel, up to the sheer on either side. They form a sort of skeleton for the boat. Most often, hard woods are desirable. White oak is a common building material for frames.
The easiest and probably best way to make frames is to cut uniform pieces of wood for each frame piece, making sure each is straight and that the grain of the wood runs straight. If the grain of the wood runs out of the piece, then the piece will probably break. Knots are also something to avoid. You may wish to cut a few extra pieces, in case some of them break during the steam-bending process.
Yes, steam-bending. Each piece is placed into an enclosed box filled with hot steam, and left inside until they are hot enough to bend.
Unfortunately, my inexperience comes into play here, as I am not perfectly certain of the correct amount of time to steam a frame piece.
I think the guideline is one hour per inch of width.
The purpose of this process, structurally, is to create a frame piece in which the grain runs perfectly with the curvature of the piece. This is much more structurally sound than a piece which is cut into a curve, because the cut piece will have grain running out of the piece, which leads to breakage.
You will probably want to construct something to bend the pieces across, and you will want to clamp them in place and leave them to cool.
The stem of the boat is a bit trickier, because it is usually thicker than the frame pieces and therefore not easily steamed. Most often is is constructed out of three or more pieces, cut and joined to create the desired curvature. The stem is joined to the front of the keel, and the frames are joined along the keel on either side.
A groove (called the rabbet) is cut into the finished stem piece. The rabbet is where the outer planks join to the stem. It can be tricky to cut a rabbet, as it usually requires a rolling bevel, (Meaning that the angle of the cut changes gradually as it progresses) and often changes in depth. There are methods for this, but they are too extensive and detailed to cover in this article.
Generally the rabbet is cut using a mallet and chisel, and a rabbet plane.
Planks are usually cut from slightly softer wood, cedar being not-uncommon.
The process of fitting the planks to each other is called Spiling. Again, it requires careful measurement and a rolling bevel, and is slightly more complicated than I am prepared to explain in this brief article.
There should be a small gap left or cut between each plank, extending two-thirds the width of the plank, but NOT going all the way through. This is later filled and sealed in a process called caulking.
Planks are joined to the stem, in the rabbet, and then bent over the frames, ending at the transom. Because they are softer woods, and are long and thin, this shouldn’t require steaming.
When cutting and spiling planks, a jack plane is useful, as is a large chisel or slick, and a draw-knife and spokeshave are invaluable.
Once the planks are fitted and fastened, the small gap between each plank should be packed with cotton (or sometimes oakum and then cotton) and sealed with pitch or tar.
Please note that power-tools, while useful for removing large amounts of material quickly, are not good for precision work. Besides which, you never know when you may not have electricity to work with. Learn to use simple word working tools. It’s more gratifying anyway, and you won’t go deaf from using them. (Unless you misuse them horribly)
Even basic boat construction is challenging and complicated, but in a pinch, it’s good to have at least some idea what you’re doing. If you are interested in furthering your study of boat building, there are numerous books published on the subject, and even a few schools and apprentice shops for wooden boat building.