Parallel shafting or tapered?
If you can supply us with this information, we can help you decide on a starting point for your spine selection. We ask for this much information because, “Anyone you ask can GUESS at what spine you need, but the more information you give US the more EDUCATED that guess can be.” If you would rather choose your own spine, here are some rules of thumb: 1) The standard string material, B-50 is requires no extra figuring. A fast flight string requires a jump in spine of 5-7 pounds. The Artificial Sinew string is heavy, thick, and stretches very much. All the negative attributes of a poor string material. This will cost your bow much in performance, and a lighter spined shaft will be needed. 2) For every inch longer than 28 you will lose approx. 5 pounds of spine. So, to compensate for that, you must add the 5 pounds per inch back into the equation. Likewise, for every inch shorter you will gain approx. 5 pounds, so you will have to subtract the 5 pounds per inch from the equation. 3) Figur
