I’ve stated several times that boat builders have their own vocabulary. The same applies to sailors. I suspect that many years ago, boat builders came up with their own words and phrases so they could confuse the heck out of cabinet makers. Sailors saw how much fun the boat builders were having, and decided to do the same to farmers. So here’s a small boat-speak dictionary; I’ll expand it as the build continues.
Backbone – In glued lapstrake construction, the backbone is considered to be the stem, the keelson, and the transom.
Batten – A long flexible piece of wood, useful in drawing a smooth curve between a series of points.
Bilge – The lower part of the hull’s interior.
Breasthook – A structural, triangular-shaped piece of wood that ties the front end of the boat together, joining the stem and the sheerstrake on either side.
Blocks (sailing) – A nautical name for a pulley.
Downhaul (sailing) – A line (rope) which “hauls down” the member to which it is attached.
Flare – as applied to either a strake or a transom, the outer edge cants away from the center.
Floors – Floors are structural members, attached to the keelson running perpendicular to the centerline, that reinforce the bottom area of the hull.
Gain – In lapstrake construction, the planks overlap one another except at the bow, where they fit flush at the stem. A gain is a tapered rabbet, or groove, cut in the preceding plank that allows the next plank to fit flush. Gains are used on planks at the stem, and on some boats at the transom.
Garboard – The lowest strake on either side of the boat, attached to the keelson.
Gunwale – Pronounced and sometimes written as “gunnel.” A rail that runs along the sheer. Whether that rail is on the inside or the outside of the sheer depends on who you talk to (see the post entitled “Etymological Confusion”).
Halyard (sailing) – The line used to raise the sail. Presumably, the term is a corruption of the phrase “haul the yard” as the line was attached to the yard on four-sided sails (see definition of spar below). On three sided sails, the halyard is attached to the peak of the sail.
Keel – The outside bottom edge of the hull. In traditional construction the keel and keelson are one single piece, with a rabbet (groove) cut to fit the garboard. In glued lapstrake construction, the keelson is a part of the backbone, garboards glued to the keelson, and then the keel glued to the garboard.
Keelson – A structural member located on the interior of the boat that runs the length of the boat and joins the stem and the transom.
Lapstrake – A type of wooden boat construction where one plank overlaps another, much like shingles on a roof. Lapstrake construction is an old technique; perhaps the most famous example of lapstrake construction is the Viking longships.
Limber – What I used to be when I was younger. In boat building, a gap or hole between two adjacent pieces to allow drainage.
Lining off – The process of determining where the planks will lie, using many battens (normally one for each plank). The purpose of lining off is to determine 1) how many planks will be required, and 2) each plank follows a smooth pleasing curve.
Lofting – Plans are necessarily drawn to scale. Really good plans also include a “table of offsets”, which is a table of various dimensions of the hull. Lofting is the process of taking those scale drawings and tables and laying them out full-size. The story goes that in old days, this work was generally performed in the loft of the boat building shop, hence the name.
Marlinspike (sailing) – Marlinspike has two definitions: 1) the skills associated with handling rope; and 2) a tool used by riggers for working splices in rope.
Molded and Sided Dimensions – terms describing the thickness of a part. The molded dimension is the thickness measured perpendicular to the skin of the hull, or the dimension of the part that follows around a mold or pattern. The sided dimension is normally constant, and is the width of the part.
Molds – Temporary pieces made up of either dimensional lumber or plywood, these define the cross-sectional shape of the boat at various locations.
Parrel (sailing) – A line or a fitting used to hold a spar (either yard or boom) against the mast.
Quarter knees – The aft corners of the boat are called the quarters. A quarter knee is a triangular shaped structural member that joins the transom and the sheerstrake. There will be one quarter knee on the port side, and one on the starboard.
Reef (sailing) – Reefing is the process of reducing sail area. To do this, reef points are sewn in parallel to the bottom edge of the sail, and lower edge of the sail rolled up and tied off. Some sails have multiple rows of reef points – use a single reef when the wind is moderately blustery, and a double or even triple reef when the wind is really snorting. I take a simpler approach. I have a single row of reef points on my sail, and if the wind is too strong for a single reef, I just don’t sail.
Scarf – Joining two shorter pieces of wood together to make a longer piece by beveling the end of each piece. The bevel is shallow, generally at a 1:8 ratio or flatter. Scarfing was essential when planking the hull, as plywood comes in sheets that are 8 feet long and all of my planks were longer than that. Scarfing can also be done on “real wood” (not plywood); I also scarfed the keelson on Tammie Norrie.
Sheer – The upper edge of the boat, from front to back on each side. The upper plank is called the sheerstrake.
Sheet (sailing) – The line (rope) which controls the position of the sail. If the sail is “sheeted in”, the sail would be pulled in close to the centerline of the boat. If the wind is blowing behind the boat, you would let the sheet out so the sail could catch as much wind as possible.
Skeg – A triangular piece of wood attached to the bottom rear section of the hull.
Spars – Spars refer to almost any stick that handles the sails, and are subdivided into many categories. The mast is a vertical spar, while the boom is a horizontal spar on the lower edge of the sail. On four-sided sails, the upper spar attached to the sail is called the yard. The bowsprit is a spar projecting from the bow of the boat, while a boomkin projects from the aft end of the boat.
Spiling – Planks on a boat are not straight when laid out flat; they are normally C-shaped and some may even have a slight S-shape. Spiling is the process of determining the shape of the plank and making a pattern so the plank can be cut out accurately.
Station – Cross sectional locations along the length of the hull. Think of slices in a loaf of bread. Generally spaced at even intervals, though not absolutely necessary. Usually, a mold (see definition above) is made for each station, so you would have a mold at Station 1, Station 2,…
Stem – The forward structural member of the boat, to which the strakes (planks) are fastened.
Transom – The rear structural member of the boat, to which the strakes (planks) are fastened. It’s also the piece that you hang the motor or rudder on to.
Tumblehome – When looking at a cross section of the boat, the shape turns inward as it approaches the top, as opposed to flaring outward.