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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. [1] It is a "frame first" method of hull construction, where the shape is determined by the framework onto which the planks are fixed. This is in contrast to "plank first" or "shell first" methods, where the outer skin of the hull is made and then reinforced by the insertion of timbers that are fitted to that shape. [2] The most common modern "plank first" method is clinker construction; in the classical period "plank first" involved joining the edges of planks with mortise and tenon joints within the thickness of the timbers, superficially giving the smooth-hull appearance of carvel construction, but achieved by entirely different means.
Compared to clinker-built hulls, carvel construction allowed larger ships to be built. This is because the fastenings of a clinker hull took all the hogging and sagging forces imposed by the ship moving through large waves. In carvel construction, these forces are also taken by the edge-to-edge contact of the hull planks.
From Middle English carvel, carvelle, carvile, kervel (“small ship; caravel”); from Old French caruelle, carvelle, kirvelle. [3] The term was used in English when caravels became popular in Northern European waters from c. 1440 onwards, and the method of hull construction took the name of the first vessel type made in that way in English and European shipyards. [4]
Carvel construction originated in the Mediterranean during the first millennium CE. It gradually replaced the edge-to-edge joining of hull planks by mortises and tenons – a "planking first" technique – which had been used by ancient Egyptians, Phoenicians and for much of classical antiquity. Archaeological evidence for this transition suggests it took place from c. 500 CE to the 9th century. Its slow adoption involved some variation and experimentation. Some ships were built using "framing-first", as opposed to the full "frame-first" system. In "framing-first", some of the framing is installed in the lower part of the hull, followed by the planking of that area, more framing is added to increase the height of the hull, and then more planking added to that. (The Romano-Celtic ship-building tradition of Northern Europe used "framing-first", but this part of Europe did not adopt the full "frame-first" method until much later, as discussed below.) [5] : 101
The changeover from planking-first to frame-first happened over the same period that the Mediterranean Square Sail rig was being replaced by lateen rig. That change has been suggested to save building, fitting out and maintenance costs (though previously it was thought to be to achieve better sailing performance – something which, against the presumptions of many maritime historians, can be shown not to have happened). The move to carvel construction is believed to be another cost-saving measure (though it is felt that this is not well understood by marine archaeologists). [6] The difficult skill of mortising planks at precisely the right angle (where the hull is curved at the turn of the bilges) is avoided. Carvel construction allows hull shape to be determined by design, whilst planking-first relies on the "eye" of the builder. Therefore fewer very highly skilled personnel are needed. [5] : 101
One of the transitional ships is the Yassi Ada ship (seventh century CE), which was excavated between 1960 and 1965. This had the lower strakes of planking fastened edge-to-edge with mortises and tenons, then the floors were added, followed by more planking joined with tenons. This brought the planking up to the waterline. Further frames were added to this next set of planking, but these continued up to the height of the intended sheerline. The strakes from the waterline up were then fastened on as carvel planking (with some wales interspersed with the regular strakes). [7] : 61
Northern Europe used clinker construction for the period discussed above, and into the 15th century (and continued to do so for many small craft into the present day). The different methods were known of by mariners in both places, but when, for instance, Mediterranean galleys were employed by the French and English during the Hundred Years' War, shipwrights familiar with carvel work had to be recruited to carry out maintenance and repairs. [8] : 51 In the 1440s interest in the caravel grew in northern waters and shipyards there started building caravels in carvel construction.
An archaeological example of an early carvel-built ship in the Baltic region is the wreck of Gribshunden, flagship of the Danish-Norwegian King Hans. The three-masted ship was built in 1485 probably near Rotterdam, and served as Hans's "floating castle" for ten years before sinking in June 1495. [9] [10]
Clinker was the predominant method of ship construction used in Northern Europe before the carvel. In clinker built hulls, the planked edges overlap; carvel construction with its strong framing gives a heavier but more rigid hull, capable of taking a variety of sail rigs. Clinker (lapstrake) construction involves longitudinal overlapping "riven timber" (split wood) planks that are fixed together over very light scantlings. A carvel boat has a smoother surface which gives the impression that it is more hydrodynamically efficient since the exposed edges of the clinker planking appear to disturb the streamline and cause drag. A clinker certainly has a slightly larger wetted area, but a carvel hull is not necessarily more efficient: for given hull strength, the clinker boat is overall lighter, and displaces less water than a heavily-framed carvel hull.
As cargo vessels become bigger, the vessel's weight becomes small in comparison with total displacement; and for a given external volume, there is greater internal hull space available. A clinker vessel whose ribs occupy less space than a carvel vessel's is more suitable for cargo which is bulky rather than dense.
A structural benefit of clinker construction is that it produces a vessel that can safely twist and flex around its long axis (running from bow to stern). This is an advantage in North Atlantic rollers, provided the vessel has a small overall displacement. Due to the light nature of the construction method, increasing the beam did not commensurately increase the vessel's survivability under the twisting forces arising if, for example, when sailing downwind, the wave-train impinges on the quarter rather than dead astern.[ clarification needed ] In these conditions greater beam widths may have made clinker vessels[ which? ] more vulnerable. As torsional forces increased in proportion to displaced (or cargo) weight, the forces incident on the hull imposed an upper limit on the size of clinker-built vessels. The greater rigidity of carvel construction became necessary for larger offshore cargo vessels. Later carvel-built sailing vessels exceeded the maximum size of clinker-built ships several times over.
A further clinker limitation is that it does not readily support the point loads associated with lateen or sloop sailing rigs. At least some fore-and-aft sails are desirable for manoeuvrability. The same problem in providing for concentrated loads creates difficulties siting and supporting a centerboard or deep keel, which is much needed when sailing across or close to the wind. Timbers can be added as necessary compromise but always with some loss of the fundamental benefits of the construction method. Clinker construction remains a useful method of construction for small wooden vessels, especially for sea-going dinghies which need to be light enough to be readily moved and stored when out of the water.
Traditional carvel methods leave a small gap between each plank that is caulked with any suitable soft, flexible, fibrous material, sometimes combined with a thick binding substance, which would gradually wear out and the hull would leak. When the boat was beached for a length of time, the planks would dry and shrink, so when first refloated, the hull would leak badly unless re-caulked, a time-consuming and physically demanding job. The modern variation is to use much narrower planks that are edge-glued instead of being caulked. With modern power sanders a much smoother hull is produced, as all the small ridges between the planks can be removed. This method started to become more common in the 1960s with the more widespread availability of waterproof glues, such as resorcinol (red glue) and then epoxy resin. [11] Modern waterproof glues, especially epoxy resin, have caused revolutionary changes in carvel and clinker construction. Traditionally, nails provided the fastening strength; now it is the glue. It has become quite common since the 1980s for carvel and clinker construction to rely almost completely on glue for fastening. Many small boats, especially light plywood skiffs, are built without any mechanical fasteners such as nails and lag screws at all, as the glue is far stronger.
Shipbuilding is the construction of ships and other floating vessels. In modern times, it normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to before recorded history.
The caravel is a small sailing ship that uses both lateen and square sails and was known for its agility and speed and its capacity for sailing windward (beating). Caravels were used by the Portuguese and Spanish for the voyages of exploration during the 15th and 16th centuries, in the Age of Discovery.
A cog was a type of ship that was used during the Middle Ages, mostly for trade and transport but also in war. It first appeared in the 10th century, and was widely used from around the 12th century onward. Cogs were clinker-built, generally of oak. Cogs were fitted with a single mast and a single square sail. They were used primarily for trade in north-west medieval Europe, especially by the Hanseatic League. Typical seagoing cogs were from 15 to 25 meters long, 5 to 8 meters wide, and were of 30–200 tons burthen. Cogs were rarely as large as 300 tons although a few were considerably larger, over 1,000 tons.
Boat building is the design and construction of boats — and their on-board systems. This includes at minimum the construction of a hull, with any necessary propulsion, mechanical, navigation, safety and other service systems as the craft requires.
Strip-built, or "strip-plank epoxy", is a method of boat building. Also known as cold molding, 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.
A lateen or latin-rig is a triangular sail set on a long yard mounted at an angle on the mast, and running in a fore-and-aft direction. The settee can be considered to be an associated type of the same overall category of sail.
A carrack is a three- or four-masted ocean-going sailing ship that was developed in the 14th to 15th centuries in Europe, most notably in Portugal and Spain. Evolving from the single-masted cog, the carrack was first used for European trade from the Mediterranean to the Baltic and quickly found use with the newly found wealth of the trade between Europe and Africa and then the trans-Atlantic trade with the Americas. In their most advanced forms, they were used by the Portuguese and Spaniards for trade between Europe, Africa and Asia starting in the late 15th century, before being gradually superseded in the late 16th and early 17th centuries by the galleon.
Clinker-built is a method of boat building in which the edges of hull planks overlap each other. Where necessary in larger craft, shorter planks can be joined end to end, creating a longer strake or hull plank.
On a vessel's hull, a strake is a longitudinal course of planking or plating which runs from the boat's stempost to the sternpost or transom. The garboard strakes are the two immediately adjacent to the keel on each side.
Medieval ships were the vessels used in Europe during the Middle Ages. Like ships from antiquity, they were moved by sails, oars, or a combination of the two. There was a large variety, mostly based on much older, conservative designs. Although wider and more frequent communications within Europe meant exposure to a variety of improvements, experimental failures were costly and rarely attempted. Ships in the north were influenced by Viking vessels, while those in the south by classical or Roman vessels. However, there was technological change. The different traditions used different construction methods; clinker in the north, carvel in the south. By the end of the period, carvel construction would come to dominate the building of large ships. The period would also see a shift from the steering oar or side rudder to the stern rudder and the development from single-masted to multi-masted ships. As the area is connected by water, people in the Mediterranean built different kinds of ships to accommodate different sea levels and climates. Within the Mediterranean area during the Medieval times ships were used for a multitude of reasons, like war, trade, and exploration.
The Humber keel was a type of single-masted, square-rigged sailing craft used for inshore and inland cargo transport around Hull and the Humber Estuary, in the United Kingdom, particularly through the late 19th and early 20th centuries.
Ancient boat building methods can be categorized as one of hide, log, sewn, lashed-plank, clinker, shell-first, and frame-first. While the frame-first technique dominates the modern ship construction industry, the ancients relied primarily on the other techniques to build their watercraft. In many cases, these techniques were very labor-intensive or inefficient in their use of raw materials. Regardless of differences in ship construction techniques, the vessels of the ancient world, particularly those that plied the waters of the Mediterranean Sea and the islands of Southeast Asia were seaworthy craft, capable of allowing people to engage in large-scale maritime trade.
A hulk was a type of medieval ship used mostly for transports. 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, though it is possible that a shipwreck found on the coast of Estonia in early 2022 might be the only known surviving example of a hulk.
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.
Discovered by divers from the French Navy Diving School in 1967, the archaeological investigations of the Roman wreck at Madrague de Giens constituted the first large-scale, "truly scientific underwater excavation[s] carried out in France". The wreck lies at around 18 to 20 metres depth off the coast of the small fishing port of La Madrague de Giens on the Giens Peninsula, east of Toulon, on the southern Mediterranean coast of France. Sank around 75–60 BCE, the vessel was found to be "a large merchantman of considerable tonnage—400 tons deadweight with a displacement of around 550 tons", making it one of the largest Roman wrecks excavated, with only the wreck at Albenga, Italy exceeding it at the time of its discovery. The vessel wrecked at Madrague de Giens measured around 40 metres in length; has a "wine glass" section which would have given better ability to sail to windward; displayed extended raking of the stem and stern; and had two masts. The hull was characterised by a reverse stempost in the shape of a ram with a big cutwater which "must have given... [the] craft high-performance sailing qualities". The ship sank while transporting a large cargo of wine and black glazed pottery from Italy. It is not known why it sank.
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.
Lashed-lug boats are ancient boat-building techniques of the Austronesian peoples. It is characterized by the use of raised lugs on the inner face of hull planks. These lugs have holes drilled in them so that other hull components such as ribs, thwarts or other structural components can be tied to them with natural fiber ropes. This allows a structure to be put together without any metal fastenings. The planks are further stitched together edge-to-edge by sewing or using dowels ("treenails") unto a dugout keel and the solid carved wood pieces that form the caps for the prow and stern. Characteristically, the shell of the boat is created first, prior to being lashed unto ribs. The seams between planks are also sealed with absorbent tapa bark and fiber that expands when wet or caulked with resin-based preparations.
Phoenician joints is a locked mortise and tenon wood joinery technique used in shipbuilding to fasten watercraft hulls. The locked mortise and tenon technique consists of cutting a mortise, or socket, into the edges of two planks and fastening them together with a rectangular wooden knob. The assembly is then locked in place by driving a dowel through one or more holes drilled through the mortise side wall and tenon.
The Serçe Limani Shipwreck or Glass Shipwreck is a shipwreck discovered in the Serçe Limani bay, southwest coast of Turkey, opposing Rhodes, in the Mediterranean Sea. The shipwreck was discovered by Donald Frey during an individual dive.