I thought of a weird idea and I'm wondering if its worth persuing...
If I took dry processed sinew threads and wove them into 6 ft of cloth, then I could lay that over wax paper at the base of a flat rectangular mold. Then if I pour hot hide glue into the mold, or brush on just enough to bind the sinew cloth,.... and maybe repeated the process with a few stacked layers of this sinew cloth. After its had time to set... Weeks or months maybe? I would have something similar to a carbon fiber, only natural, but strong! And by laying the fibers in specific directions maybe I can make it stronger lengthwise, or diagonal to prevent the bow twisting... If I made one big sheet, I could end up with enough of this material to back dozens of bows.
You guys think this could work? Or is it a huge waste of time? Lets put it this way: would anyone want to buy a bow sized strip of this material?