This started as a frustrated woodworker trying to build hexagonal shapes with his table saw. He needed to cut a precise 22.5 degree angle on each piece and it just wasn't turning out right. A lot of participants suggested a variety of measuring devices and jigs, but some conceded that a table saw wasn't precise enough to do the job. Someone pointed out that with hexagons, any error in the bevel was multiplied by a factor of 16, so it was going to be tough going. Finally someone suggested that there were router bits out there that precisely cut 22.5 degree bevels for precisely this kind of task. That seemed to be the solution the woodworker was looking for.