Seriously though, I've been thinking about it. How about getting laminates of Ipe, thin ones, and a few of another to act as a core wood and allow for a good gluing surface for the sinew. Build a form and glue the laminations together. Belly of a couple lams of ipe then one of the bellywood and then start glueing the sinewbacking to it. Make sure to put horn overlays on the tips to take the shock well. This would allow you to get the shape of the bow and the tension from the sinew and the Ipe for compresion. I think this would work.