I should add that I learned my technique from Steve (Badger). I set my caul up so that there are places where I can touch the back of the bow, and heat the limb until the back is hot, not just the belly. I then keep heating to keep the back hot for 10-20 minutes. I spend 30-40 minutes on each limb. I keep the heat gun fairly close to the limb, maybe a couple inches away.