I have a long made out of iron wood that,I made and to back it with sineu. At widest point it's 1" and 58" long. I have one deer I got some from to use and I know I will need more. About how many deer do you think I will need to finish the bow?
12-15 back strap sinews will easily do at least two layers on your bow.
12-15 backstraps!? holy animal protein! That should do 2 bows!
I think 12-15 leg sinews should be about right for one bow...
Just a bad guess I suppose. I have limited sinew experience? Maybe 8-10 bows?
If it's pretty long leg sinew, 8 tendons should do it. So a mature deer will provide you with half of what you need. Smaller deer might take more and front legs are generally shorter. It also depends on how thick you want it. I'd go at least 2 and better yet 3 courses (or layers).
Back sinew is easier to process but will take a couple more deer's worth since you generally only get 1 thin piece from each backstrap (2 per deer). You'll want at least 8 strips or 4 deer's worth.