I just received my Amazon order for a digital protractor. After receiving it, the instructions listed the read out granularity was 0.1 while the accuracy was only 0.3 deg. Great, I guess you get what you pay for. In the end I doubt 0.3 deg will amount to much other than an imperceptible amount of clearance. Either way, I checked the measurements against a mechanical protractor and .2 deg is just guess work at that point. Completed bending the horn by pressing it into a piece of ash wood I cut to 8deg on my bandsaw. Then testing and adjusting with my digital protractor.