You can rasp out a shallow 6"-ish trough along the limb that feathers out at very shallow angles with the limb. Then form a matching convex belly patch. Meticulous rasp and/or belt sander work is neccessary. Then score the gluing surfaces, mix up some Urac, and pressure fit the patch into place with your fingers. Don't clamp with Urac unless the patch wants to slide off, and only then just clamp using just enough pressure to hold in place. (A tip from Dean Torges) When dry, rasp, scrape, and block sand the patch to blend in with the rest of the limbs. Of course, leave it thicker than before if you are trying to correct a hinge.