On a vessel's hull, a strake is a longitudinal course of planking or plating which runs from the boat's stempost (at the bows) to the sternpost or transom (at the rear). The garboard strakes are the two immediately adjacent to the keel on each side.
The word derives [1] [2] from traditional wooden boat building methods, used in both carvel and clinker construction. In a metal ship, a strake is a course of plating.
In small boats strakes may be single continuous pieces of wood. In larger wooden vessels strakes typically comprise several planks which are either scarfed, or butt-jointed and reinforced with a butt block. Where the transverse sections of the vessel's shape are fuller, the strakes are wider; they taper toward the ends.
In a riveted steel ship, the strakes were usually lapped and joggled (one strake given projections to match indentions in the one adjoining), [3] but where a smoother finish was sought they might be riveted on a butt strap, though this was weaker. In modern welded construction, the plates are normally butt-welded with full penetration welds all round to adjoining plates within the strake and to adjoining strakes.
In boat and ship construction, strakes immediately adjacent to either side of the keel are known as the garboard strakes or A strakes. The next two are the first broad or B strake and second broad or C strake. Working upward come the bottom strakes, lowers, bilge strakes, topside strakes, and uppers also named sequentially as the D strake, E strake, etc. The uppermost along the topsides is called the sheer strake. [4] Strakes are joined to the stem by their hood ends. [5]
A rubbing strake was traditionally built in just below a carvel sheer strake. It was much less broad but thicker than other strakes so that it projected and took any rubbing against piers or other boats when the boat was in use. In clinker boats, the rubbing strake was applied to the outside of the sheer strake. Many current pleasure craft reflect this history in that they have a mechanically attached (and therefore replaceable) rub rail at the location formerly occupied by a rubbing strake, often doubling to cover the joint between a GRP hull and its innerliner. Inflatable dinghies and RIBs usually have a rubbing strake (typically a glued-on rubber extrusion) at the edge. [6]
A "stealer" is a short strake employed to reduce the width of plank required where the girth of the hull increases or to accommodate a tuck in the shape. [7] It is commonly employed in carvel and iron/steel shipbuilding, but very few clinker craft use them.
Longships were a type of specialised Scandinavian warships that have a long history in Scandinavia, with their existence being archaeologically proven and documented from at least the fourth century BC. Originally invented and used by the Norsemen for commerce, exploration, and warfare during the Viking Age, many of the longship's characteristics were adopted by other cultures, like Anglo-Saxons, and continued to influence shipbuilding for centuries.
The koch was a special type of small one or two mast wooden sailing ships designed and used in Russia for transpolar voyages in ice conditions of the Arctic seas, popular among the Pomors.
A cog is a type of ship that first appeared in the 10th century, and was widely used from around the 12th century on. Cogs were clinker-built, generally of oak. These vessels were fitted with a single mast and a square-rigged single sail. They were mostly associated with seagoing trade in north-west medieval Europe, especially the Hanseatic League. Typical seagoing cogs ranged from about 15 to 25 meters in length, with a beam of 5 to 8 meters and were 30–200 tons burthen. Cogs were rarely as large as 300 tons although a few were considerably larger, over 1,000 tons.
Carvel built or carvel planking is a method of boat building in which hull planks are laid edge to edge and fastened to a robust frame, thereby forming a smooth surface. Traditionally the planks are neither attached to, nor slotted into, each other, having only a caulking sealant between the planks to keep water out. Modern carvel builders may attach the planks to each other with glues and fixings.
Boat building is the design and construction of boats and their systems. This includes at a minimum a hull, with propulsion, mechanical, navigation, safety and other systems as a craft requires.
Strip-built, or "strip-plank epoxy", is a method of boat building. Also known as cold moulding, the strip-built method is commonly used for canoes and kayaks, but also suitable for larger boats. The process involves securing narrow, flexible strips of wood edge-to-edge around temporary formers. The temporary formers are usually created via a process called "lofting" whereby a set of tables is used to generate the shapes of the formers. The strips are glued edge-to-edge with epoxy. It is effectively a modern form of carvel which needs no caulking and which is both stiffer and more watertight. In a small boat, there will be just one layer of strip-planking, but larger vessels may have two or three layers which,, forms a light, strong, and torsionally stiff monococque.
The Gokstad ship is a 9th-century Viking ship found in a burial mound at Gokstad in Sandar, Sandefjord, Vestfold, Norway. It is displayed at the Viking Ship Museum in Oslo, Norway. It is the largest preserved Viking ship in Norway. It is also the largest Viking ship ever found.
A deck is a permanent covering over a compartment or a hull of a ship. On a boat or ship, the primary or upper deck is the horizontal structure that forms the "roof" of the hull, strengthening it and serving as the primary working surface. Vessels often have more than one level both within the hull and in the superstructure above the primary deck, similar to the floors of a multi-storey building, that are also referred to as decks, as are certain compartments and decks built over specific areas of the superstructure. Decks for some purposes have specific names.
Clinker built is a method of boat building where the edges of hull planks overlap each other. Where necessary in larger craft, shorter planks can be joined end to end into a longer strake or hull plank. The technique developed in northern Europe and was successfully used by the Anglo-Saxons, Frisians, Scandinavians, and typical for the Hanseatic cog. A contrasting method, where plank edges are butted smoothly seam to seam, is known as carvel construction.
The bow is the forward part of the hull of a ship or boat, the point that is usually most forward when the vessel is underway. The aft end of the boat is the stern.
The Hjortspring boat is a vessel designed as a large canoe, from the Scandinavian Pre-Roman Iron Age. It was built circa 400–300 BC. The hull and remains were rediscovered and excavated in 1921–1922 from the bog of Hjortspring Mose on the island of Als in Sønderjylland, southern Denmark. The boat is the oldest find of a wooden plank ship in Scandinavia and it closely resembles the thousands of petroglyph images of Nordic Bronze Age ships found throughout Scandinavia. The vessel is a clinker-built wooden boat of more than 19 metres length overall, 13.6 metres long inside, and 2 metres wide. Ten thwarts that could have served as seats, span the boat with room for two persons each; this suggests space for a crew of at least 20 who propelled the boat with paddles. The boat would have weighed an estimated 530 kilograms (1,168 lb), making it easily portable by its crew.
A chine in boat design is a sharp change in angle in the cross section of a hull. The chine typically arises from the use of sheet materials as the mode of construction.
A caïque is a traditional fishing boat usually found among the waters of the Ionian or Aegean Sea, and also a light skiff used on the Bosporus. It is traditionally a small wooden trading vessel, brightly painted and rigged for sail. The caïque is also a typical case of positioning the widest beam far aft, with a long sharp bow.
Shell plating is the outer-most structure on the hull of a steel or aluminum ship or boat.
A hulk was a type of medieval sea craft, a technological predecessor of the carrack and caravel. The hulk appears to have remained a relatively minor type of sailing ship apparently peculiar to the Low Countries of Europe where it was probably used primarily as a river or canal boat, with limited potential for coastal cruising. The only evidence of hulks is from legal documents and iconography.
The Sparrow-Hawk was a 'small pinnace' similar to the full-rigged pinnace Virginia that sailed for the English Colonies in June 1626. She is the earliest ship to participate in the first decades of English settlement in the New World to have survived to the present day.
The pinas, sometimes called "pinis" as well, is one of two types of junk rigged schooners of the east coast of the Malay peninsula, built in the Terengganu area. This kind of vessel was built of Chengal wood by the Malays since the 19th century and roamed the South China Sea and adjacent oceans as one of the two types of traditional sailing vessels the late Malay maritime culture has developed: The bedar and the pinas.
Maritime travel experienced a large leap in the capabilities of seafaring vessels thanks to technological improvements in shipbuilding in the early modern era. Europe, Asia, and the Middle East all saw improvements on prior construction techniques, contributing to the Age of Discovery. As a result, the introduction of these technologies in the production of naval vessels was critical as they allowed nations that utilized these advancements to ascend to a state that could expand its influence at a far greater range. In military engagements, the exploration of new lands and potential colonies, or the transportation of goods for trade, better shipbuilding techniques coincided with prosperity. It is during this time that the practice of naval architecture appeared, as skilled designers could produce designs that had an enormous impact in ship performance and capabilities.
Fusi Yama was a composite barque ship of roughly 556 tons, built in 1865 by Alexander Stephen & Sons at Glasgow for Killick Martin & Company, London.