Did you slowly draw the bow (a few inches per pull, over a lot of pulls?), or right back to 30? I am not an expert by any means, but I am under the impression that you have to work the bow out to get to full draw. My advice would be to stick to boards for a bit. Make one unbacked that works and shoots first before trying to back it. If you can make one that shoots unbacked, you can make one backed. One has to crawl before he can run. I have finished 4 bows so far. 3 red oak boards (2 kids bows), and an osage stave.