The earliest wooden boat, a dugout, dates from about 6000 bc and was discovered in what is now The Netherlands. A dugout consists of a log hollowed out with tools or by controlled burning. Early boat builders also constructed craft of sewn planks. This form of construction was used extensively throughout history. Sewn-timber construction was common among the peoples of the Pacific Islands, whose dugouts often had topsides formed of irregular sewn pieces of timber.
Dugout Canoes
Dugout canoes are made from hollowed-out tree trunks and thus are naturally buoyant. They may be plain or elaborately decorated like the two pictured.
Craft constructed of wood planks appear to have been developed gradually from the modified dugout by about 5000 bc, or even earlier in some regions. Log construction methods were also used for ancient Egyptian boats, in which short planks of timber were bolted edge to edge to form a hull.
Framing and planking are the basic components of modern wooden boats. The frame is used to support and stiffen the hull, including the stem, keel, keelson, ribs, knees, and wales. The planking is the outer shell that is fastened to the framing.
I. Lapstrake Construction
In northern Europe, lapstrake, or overlapping, construction was developed to a high order by the 9th century ad, particularly by the Scandinavians. Lapstrake is also known as clinch-built or clinker-built construction. Planks apparently were split off a log by means of wedges, or they were hewn and assembled on the keel, one after another beginning with the garboard, the lowest. In the Viking ships and boats of the 10th century and somewhat later, lashings were still used to secure the planks to the frames. Such construction resulted in a very flexible hull, yet one of relatively great strength. The lashings eventually were replaced by through fastenings, that is, by pegs, and later were replaced by nails driven into the planking and frames.
Viking Ship
This Viking ship, on display at the Viking Museum in Oslo, Norway, is an example of lapstrake construction. In Viking ships of the 9th century and later, external planks were overlapped and lashed to the ship’s frame, producing a strong, flexible hull.
In lapstrake construction the longitudinal seams of the planking are formed by overlapping the edges enough to allow continuous nailing. Thus, the skin, or exterior planking, adds strength to the boat. Frames are then added to give the required stiffness of form. Originally the frames were hewn of natural-crook timber, including root or limb knees and crooked trunks. Steam-bent frames became popular in the early 19th century.
II. Carvel Construction
The smooth-planked, or carvel-built, boat was developed in the Mediterranean region and was probably a natural evolution of the craft constructed of short planks bolted edge to edge used by the ancient Egyptians. Plank and frame construction was probably fully developed before ancient Greece rose to maritime prominence. As in lapstrake construction, the use of pegs probably preceded the use of metal fastenings between plank and framing.
Constructing a Wooden Whaler
Wooden ships like this 8-m (26-ft) whaler are built in stages. Because the timber must be steamed into the properly curved shapes, a fairly complex skeleton and bracing system is needed. Here, workers place horizontal planks called strakes to form the smooth curve of the hull on the starboard side of the ship.
A framing system made of almost equally spaced transverse frames fastened to a continuous keel and strengthened by a pair of gunwales running from bow to stern was a logical step in the development of smooth-planked boats. The problem of seam leakage was solved by using wood tar and caulking material, as in earlier lapstrake craft.
In so-called smooth-lap construction, developed in the 19th century, plank edges are rabbeted, or shaped, so that they lap and still remain smooth at the seams; the rabbeted laps are nailed in the usual lapstrake manner. See Woodworking: Carpentry.
In the early 20th century the use of lapstrake construction decreased, while carvel construction became more popular. The shift was caused largely by the need for extreme structural strength necessitated by the use of motors in small boats. Carvel construction also better met the demand for fast sailing craft used for racing.
III. Plywood Construction
Plywood boat construction began in the United States about 1918 and developed rapidly; the two basic types are paneled and molded. Panel construction involves securing flat sheets of plywood to transverse frames and to the keel and other units that supply longitudinal strength; it is used only with chine-model boats, that is, those with flat bottoms or V-bottoms. The amount of compound curve that may be used in a plywood panel is extremely limited.
Fishing in Newfoundland and Labrador
Plywood panel boats are flat-bottomed, a hull shape that lends itself well to fishing. Here, workers on a fishing boat haul a fish trap aboard off the coast of Cape Spear, the easternmost point in North America.
In molded-plywood construction the form of the boat is established by temporary transverse frames, or molds, and by longitudinal battens (thin, narrow strips of lumber often used to seal or reinforce joints), over which the planking is placed in two or three layers. The first skin is laid on diagonally and secured to the form by staples. Two or three skins are used, and after stapling, the mold is moved into a heating and pressure stage in which adhesion of the skins is accomplished. After adhesion, stiffeners and joinery are added; these usually include keelson, shoe, gunwale, guards, thwarts, decking, outside stem, transom (in a square-stern boat), and centerboard case and mast step (in a sailing hull).
Dugout Canoes
Dugout canoes are made from hollowed-out tree trunks and thus are naturally buoyant. They may be plain or elaborately decorated like the two pictured.
Craft constructed of wood planks appear to have been developed gradually from the modified dugout by about 5000 bc, or even earlier in some regions. Log construction methods were also used for ancient Egyptian boats, in which short planks of timber were bolted edge to edge to form a hull.
Framing and planking are the basic components of modern wooden boats. The frame is used to support and stiffen the hull, including the stem, keel, keelson, ribs, knees, and wales. The planking is the outer shell that is fastened to the framing.
I. Lapstrake Construction
In northern Europe, lapstrake, or overlapping, construction was developed to a high order by the 9th century ad, particularly by the Scandinavians. Lapstrake is also known as clinch-built or clinker-built construction. Planks apparently were split off a log by means of wedges, or they were hewn and assembled on the keel, one after another beginning with the garboard, the lowest. In the Viking ships and boats of the 10th century and somewhat later, lashings were still used to secure the planks to the frames. Such construction resulted in a very flexible hull, yet one of relatively great strength. The lashings eventually were replaced by through fastenings, that is, by pegs, and later were replaced by nails driven into the planking and frames.
Viking Ship
This Viking ship, on display at the Viking Museum in Oslo, Norway, is an example of lapstrake construction. In Viking ships of the 9th century and later, external planks were overlapped and lashed to the ship’s frame, producing a strong, flexible hull.
In lapstrake construction the longitudinal seams of the planking are formed by overlapping the edges enough to allow continuous nailing. Thus, the skin, or exterior planking, adds strength to the boat. Frames are then added to give the required stiffness of form. Originally the frames were hewn of natural-crook timber, including root or limb knees and crooked trunks. Steam-bent frames became popular in the early 19th century.
II. Carvel Construction
The smooth-planked, or carvel-built, boat was developed in the Mediterranean region and was probably a natural evolution of the craft constructed of short planks bolted edge to edge used by the ancient Egyptians. Plank and frame construction was probably fully developed before ancient Greece rose to maritime prominence. As in lapstrake construction, the use of pegs probably preceded the use of metal fastenings between plank and framing.
Constructing a Wooden Whaler
Wooden ships like this 8-m (26-ft) whaler are built in stages. Because the timber must be steamed into the properly curved shapes, a fairly complex skeleton and bracing system is needed. Here, workers place horizontal planks called strakes to form the smooth curve of the hull on the starboard side of the ship.
A framing system made of almost equally spaced transverse frames fastened to a continuous keel and strengthened by a pair of gunwales running from bow to stern was a logical step in the development of smooth-planked boats. The problem of seam leakage was solved by using wood tar and caulking material, as in earlier lapstrake craft.
In so-called smooth-lap construction, developed in the 19th century, plank edges are rabbeted, or shaped, so that they lap and still remain smooth at the seams; the rabbeted laps are nailed in the usual lapstrake manner. See Woodworking: Carpentry.
In the early 20th century the use of lapstrake construction decreased, while carvel construction became more popular. The shift was caused largely by the need for extreme structural strength necessitated by the use of motors in small boats. Carvel construction also better met the demand for fast sailing craft used for racing.
III. Plywood Construction
Plywood boat construction began in the United States about 1918 and developed rapidly; the two basic types are paneled and molded. Panel construction involves securing flat sheets of plywood to transverse frames and to the keel and other units that supply longitudinal strength; it is used only with chine-model boats, that is, those with flat bottoms or V-bottoms. The amount of compound curve that may be used in a plywood panel is extremely limited.
Fishing in Newfoundland and Labrador
Plywood panel boats are flat-bottomed, a hull shape that lends itself well to fishing. Here, workers on a fishing boat haul a fish trap aboard off the coast of Cape Spear, the easternmost point in North America.
In molded-plywood construction the form of the boat is established by temporary transverse frames, or molds, and by longitudinal battens (thin, narrow strips of lumber often used to seal or reinforce joints), over which the planking is placed in two or three layers. The first skin is laid on diagonally and secured to the form by staples. Two or three skins are used, and after stapling, the mold is moved into a heating and pressure stage in which adhesion of the skins is accomplished. After adhesion, stiffeners and joinery are added; these usually include keelson, shoe, gunwale, guards, thwarts, decking, outside stem, transom (in a square-stern boat), and centerboard case and mast step (in a sailing hull).
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