The idea of bending wood for the sides of a guitar is a fairly simple concept. It involves primarily 2 things, heat and moisture. Some other factors that might come into play would be the thickness of the wood, the amount of heat being used, and the speed at which you're forcing the bend to happen. Too much heat and your beautiful, exotic wood scorches and makes your shop smell like toasted marshmallows. Really, it does. At least that's what happened when I was practicing with some walnut scraps a long time ago. And if you force the bend to happen too quickly or leave your sides too thick you risk cracking and splitting. So, the moral of the story is go slow and don't use too much heat. I spent some time today bending ziricote sides in my side bending machine. Before I was able to do that though I finished making a mold for the bender in the shape of a new grand concert size that I've been working on.