David, I would use tight bond 2 to apply the sinew, the hide glue would be more affected by the weather where you are. as I told you at camp, I had a couple of bows that were rawhide backed with hide glue, that were on a table and the fog rolled in, the rawhide curled up on them. I had to re-apply using tb2. I am sure the natives used wax or lard-based materials for weather proofing, but the tb2 willl withstand the weather. the snake backed bow I had at camp hunted in the late season in pouring rain and was not affected by the moisture.