On roughing out IPE bows:
There are many different species of woods which are tagged "IPE". Both IPE boards I've used would tear out in a heartbeat when a draw knife or spokeshave was used. Worse yet direction of the cutting didn't seem to matter much. If you lack a bandsaw, a fast and relatively cheap way to rough out such wood is to carefully wielded 4.5" angle grinder fitted with a 36 grit flap. It eats through wood very quickly. I do it outdoors, wear a decent dust respirator and blow myself down with a leaf blower, throw the clothes in the washer then shower afterwards. Tillering is then with alternate use of rasps and scrapers. A tip for marking the dark oily stuff: smooth the surface with a scraper, scribe the line, rub with chalk and then wipe off chalk across the scribed line.
c.d.