Composite Bow - Construction and Materials

Construction and Materials

The wooden core gives the bow its shape and dimensional stability. It is often made of multiple pieces, joined with animal glue in V-splices, so the wood must accept glue well. Pieced construction allows the sharp bends that many designs require, and the use of woods with different mechanical properties for the bending and nonbending sections. The wood of the bending part of the limb ("dustar") must endure intense shearing stress, and denser woods such as hard maples are normally used in Turkish bows. Bamboo, and wood of the mulberry family, are traditional in China. Some composite bows have nonbending tips ("siyahs"), which need to be stiff and light; they may be made of woods such as Sitka spruce.

A thin layer of horn is glued on to what will be the belly of the bow, the side facing the archer. Water buffalo horn is very suitable, as is horn of several antelopes such as gemsbok, oryx, ibex, and that of Hungarian grey cattle. Goat and sheep horn can also be used. Most forms of cow horn are not suitable, as they soon delaminate with use. The horn can store more energy than wood in compression.

The sinew, soaked in animal glue, is then laid in layers on the back of the bow; the strands of sinew are oriented along the length of the bow. The sinew is normally obtained from the lower legs and back of wild deer or domestic ungulates. Traditionally, ox tendons are considered inferior to wild-game sinews since they have a higher fat content, leading to spoilage. Sinew will extend farther than wood, again allowing more energy storage.

Hide glue or gelatin made from fish gas bladders is used to attach layers of sinew to the back of the bow, and to attach the horn belly to the wooden core.

Stiffening laths, if used, are attached. Both horn and laths may be bound and glued with further lengths of sinew. After months of drying the bow is ready for use. Further finishing may include thin leather or waterproof bark, to protect the bow from moisture, and recent Turkish bows were often highly decorated with colourful paints and gold leaf.

Strings and arrows are essential parts of the weapon system, but no type of either is specifically associated with composite bows throughout their history.