Don't try and take off all the wood at once. Just get a nice taper going with the thickest part near the handle (you didn't mention if the bow is supposed to bend through the handle or not), and let it taper to 1/2" or so near the tips. Then get the wood bending (called floor tillering because you can check for bend by pushing the tip against the floor). If it doesn't bend immediately, that's fine, just take off a few strokes of wood and try again. Your goal is to just get the wood bending at this point, not to finish the bow. Then you can put a string on the bow and work on getting it to pull to the weight you want. Brace the bow when you can, and keep going until it's at full draw. This process is explained in a lot more depth in TBB volume 1, which I highly recommend reading.