It is hard to find a good source for sinew. My friend butchered deer until three years ago,so I had a good supply back then. Not anymore. Back then I sinew backed Osage, Black Locust, Elm, Hickory, American Horn beam, and even tried Walnut. Now ,when I do build a bow it is longer self bows. The same woods, but 58 to 63 inches long with my short draw.