As with any wood-bending project, choose material with grain that runs parallel to the surface and avoid any defects so the wood does not fail during bending. If you are cutting wood from a tree, the trunk will usually possess the straightest grain, but a large, straight limb will do, too. There are several advantages to felling your own tree. One advantage in harvesting your own lumber is the wood can be split following the grain, so the grain exactly follows the surface of the blank cut from the wood. This type of cut helps keep the grain from running out and causing possible cracks. Another advantage to felling your own lumber is you can cut boards sawn with the grain and air-dry them. Air-dried wood has better bending properties than kiln-dried lumber.
In this case, I used the trunk of a tree that measured about12″ (30 cm) in diameter. The length of a bow can vary from 5′ (150 cm) or 6′ (180 cm) for a long bow down to 4′ (120 cm) for a short bow. A bow can be bent just in the middle or also curved backward at the ends to add more power and speed. We’ll be making the type that curves backward at the ends, which is called a recurved bow.
Though cutting your own lumber gives you an advantage when it comes to grain, there is not a great advantage to using green wood for a bow before it is properly seasoned, or dried. Green wood does bend quite easily, but much of the power from a bow comes from the wood as it tries to straighten itself out after bending. Green wood tends to stay curved, which reduces the power stored in the bow. Constant use also will soften the wood, further reducing the bow’s strength. Because air-dried wood has better bending qualities than kiln-dried wood, I cut the wood for my bow into rough billets and allowed the wood to dry for 1 year before bending it. If you are not up for the task of splitting wood, the wood can be cut into rectangular blanks on the band saw or with a handsaw.
To decrease the drying time, blanks can be cut out to nearly their finished size and shape and then air-dried for about 6 months. Either way, be sure to seal the ends with glue or tape to prevent cracking. A bow has a thick center part, known as the handle, with ends that taper out toward the end, which are called the limbs.
Wider, thicker boards cut from green logs can also be bent, but in most cases, there seems to be no clear advantage to steam bending green boards over steaming dried wood. In fact, adding steam to green wood can oversaturate the fibers in the wood, causing them to crush on the inside of the radius as bending pressure is applied.