In clans or social groups that used wooden self bows (bows made entirely from one piece of wood) bows would sometimes be crafted by the individual user; however, even with fairly simple bow designs it was often easier to rely upon a few skilled bowyers within the group. By working in groups more could be accomplished. In medieval England, for example, professional bowyers produced thousands of bows required for that country’s military. These bowyers could reportedly make an English longbow in as little as two hours. Wooden selfbows normally take from 5-15 hours of work depending on the skill of the bowyer and the challenges set by the piece of wood. Modern amateurs find it satisfying to make functional self bows with beginner's skills and few tools.
Cultures that used composite bows (bows made of several materials, often horn, wood, and sinew) had to rely on skilled craftsmen. Composite bows could be made relatively short, heavily recurved, and highly effective but the constituent materials had to be put under enormous stress and the bow’s limbs needed to be perfectly aligned. These demands required experienced bowyers who were willing to spend a great deal of time crafting their weapons. Cultures such as the Mongols made effective military use of powerful composite bows for millennia; the limited records indicate that only a minority of men in these cultures ever made bows. The early modern Turkish bowyers are widely thought to have been the most skilled. Because the glue used to apply each lamination was allowed to dry for months, Turkish flight bows took up to a year to produce. The short, very recurved, sinew-horn-wood composite bows were exquisitely crafted and pushed the natural materials to their limits. In the 1500’s one such Turkish flight bow set the record for the longest shot, 846 meters (925 yards), a record that stood until the 20th century and the application of modern material science.
Glass bowyers who create fiberglass laminated bows, bows consisting of wood sandwiched by fiberglass layers, can create somewhat more standardized bows as fiberglass, not the wood, is the load bearing component and keeps the bow from breaking. The wood in a fiberglass bow serves the purposes of separating the fibreglass laminates, and of resisting shear. Most of the stress of a bent spring occurs in the surface layers, and the further apart they are, the greater the stress on them. A solid fibreglass bow tends to be heavy, and heavy bow limbs shoot more slowly, other things being equal, than light ones. The limbs of a laminated bow can be lightened by the use of lighter materials such as wood. This wood must, however, be sufficiently strong to withstand the intense stress of shear, caused by the backing strip (that nearest the target) being under tension and the belly strip (that nearest the archer) being under compression. American rock maple has been extensively used for center laminations, strips being machined for the purpose so that the thickness and therefore the strength of the resulting limb can be predicted with reasonable accuracy.
The wood must provide a perfect gluing surface and needs to be completely free of grease for most synthetic glues. Amateur bowyers clean the wood with acetone prior to gluing, a fraught business since acetone is easily absorbed through the skin, and impossible to prevent soaking into leather gloves or dissolving plastic gloves. Amateurs often use epoxy resins; those manufactured specifically to resist shear are best for the purpose although it is essential to follow the exact proportions given by the manufacturers, by measuring quantities with a chemical balance if necessary.
Failures of fiberglass bows commercially produced are not unknown, and careful inspection of the broken limbs usually indicates that the bow has failed in shear. The greatest care must be taken to feather any wooden inserts, especially at the handle riser (the thickened part in the middle of the bow) and less importantly at the nocks (and axle mounts, in wheeled compound bows) as the shear stress seems to need a weak point to start a split. Feathering of the wood in between the fibreglass laminates must be accompanied by perfectly even pressure over the whole width of the limb, lest the centre part pucker up under clamping pressure and form either a void or a weakness filled only with glue.
Common practice is to bind a bow in many strips of rubber cut from car or bicycle inner tubes to apply great and even pressure, and leave the glue to cure for several days before unwrapping. Binding in this way tends to put greatest pressure on the edges of the laminates, encouraging puckering, and weak thickening, of the middle strip of the bow limb. This is avoided by putting strips of soft, flexible material such as thin hardboard, above the top laminate before the rubber binding is applied. The strips are made about 12mm narrower than the bow limb, and, concentrating the pressure down the middle of the limb, greatly assist in obtaining a flat section during the glue curing time. These strips are discarded after the bow is released from the bow form.
Assuming a bow will not fail during shooting, other factors such as efficiency, aesthetics, and noise during shooting can all be important. How these factors affect the bows' design and construction depends on the purpose of the bow and preferences of the user.