Basically make it 68" long(for 28" draw), 2" at the fades and out the limbs to the last 6" or so then taper to the tips. You could probably go with 1 3/4" instead of 2". Another bow would be a Cherokee style, bend through the handle bow of about 1 1/4" to 1 1/2 " for most of its length. This style works well with single side nocks on each end instead of a nock on each side of the limb tips. If your stave has a bit of prop twist you can use the side nocks to help control the twist. With a bow that bends through the handle you are allowing the entire bow to handle the stresses instead of each limb. Pat
ps. Paul Comstock has a great little book, "The Bent Stick"(inexpensive) that explains this and other methods for the weaker white woods.