Longbow - Design and Construction

Design and Construction

Because the longbow can be made from a single piece of wood, it can be crafted relatively easily and quickly. Amateur bowyers today can make a longbow in about ten to twenty hours, while highly skilled bowyers, such as those who produced medieval English longbows, can make wooden longbows in just a few hours.

One of the simpler longbow designs is known as the self bow, by definition made from a single piece of wood. Traditional English longbows are self bows made from yew wood. The bowstave is cut from the radius of the tree so that the sapwood (on the outside of the tree) becomes the back two thirds and the belly, the remaining one third, is heartwood. Yew sapwood is good only in tension, while the heartwood is good in compression. However, compromises must be made when making a yew longbow, as it is difficult to find perfect unblemished yew. The demand for yew bowstaves was such that by the late 16th century mature yew trees were almost extinct in northern Europe. In other desirable woods such as Osage orange and mulberry the sapwood is almost useless and is normally removed entirely.

Longbows, because of their narrow limbs and rounded cross-section (which does not spread out stress within the wood as evenly as a flatbow’s rectangular cross section), need to be less powerful, longer or of more elastic wood than an equivalent flatbow. In Europe the last approach was used, with yew being the wood of choice, because of its high compressive strength, light weight and elasticity. Yew is the only widespread European timber that will make good self longbows, and has been the main wood used in European bows since Neolithic times. More common and cheaper hard woods, including elm, oak, ash, hazel and maple, are good for flatbows. A narrow longbow with high draw-weight can be made from these woods, but it is likely to take a permanent bend (known as "set" or "following the string") and would probably be outshot by an equivalent made of yew.

Wooden laminated longbows can be made by gluing together two or more different pieces of wood. Usually this is done to take advantage of the inherent properties of different woods: some woods can better withstand compression while others are better at withstanding tension. Examples include hickory and lemonwood, or bamboo and yew longbows: hickory or bamboo is used on the back of the bow (the part facing away from the archer when shooting) and so is in tension, while the belly (the part facing the archer when shooting) is made of lemonwood or yew and undergoes compression (see bending for a further explanation of stresses in a bending beam). Traditionally made Japanese yumi are also laminated longbows, made from strips of wood: the core of the bow is bamboo, the back and belly are bamboo or hardwood, and hardwood strips are laminated to the bow's sides to prevent twisting. Ready-made laminated longbows are available for purchase.

Any wooden bow must have gentle treatment and be protected from excessive damp or dryness. Wooden bows may shoot as well as fiberglass, but they are more easily dented or broken by abuse. Bows made of modern materials can be left strung for longer than wood bows, which may take a large amount of set if not unstrung immediately after use.