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Concept
Self bow
Résumé
A self bow or simple bow is a bow made from a single piece of wood. Extra material such as horn nocks on the ends, or built-up handles, would normally be accepted as part of a self bow. Some modern authorities would also accept a bow spliced together in the handle from two pieces of wood.
An effective self bow can be made from widely available local material in most inhabited parts of the world, with limited tools whose functions include chopping, shaving, and scraping. A day of work may be needed, starting with a seasoned stave; a composite bow requires a week's work, and could possibly take up to several years, starting with a much greater range of materials and skills. Self bows must be approximately the height of the archer if they are to allow a long draw, and they are less efficient in the specialized art of flight archery. Well-designed composite bows of high draw-weight give higher arrow velocity, and the bow itself is shorter. However, the hide glue that holds a composite bow together absorbs water and will dissolve if soaked; the wood of self bows is less sensitive to humidity.
At the weights more usual for modern amateurs, the greater density of horn and sinew compared to wood usually cancels any advantage of composite construction. For most practical non-mounted archery purposes, self bows can perform as well as composite; "the initial velocity is about the same for all types of bow... within certain limits"
In many parts of the world including much of Africa, the Americas, northern Europe, and Southern Asia, the great majority of traditional bows are self bows. The first bow artifacts, the Stellmoor and Holmegaard artifacts of Northern Europe, are self bows. The Stellmoor bow was made from the heartwood of a Scots pine while the oldest Holmegaard bows were carved from small-diameter elms. In primitive flight archery competitions, bows inspired by the design of the Holmegaard bows perform very well because of their light, non-bending tips.
In most inhabited areas, common timbers can be made into high-quality self bows.
Source officielle
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