Here's a problem - How to locate a corner when the part is at an angle.
Perhaps you have to drill an angled hole or slot a certain distance from the "corner" of a square part. Typically the problem is confounded by the fact that the "corner" has been rounded during deburring. You need a Pacman-Machinist School Tool
Machinist School brother Dave Renfro invented the Pacman to solve this problem. A 1" cylinder with a 90 degree v-groove solves the problem. An edge finder can be used to locate the edge of the Pacman (1/2" from the corner). Using the Pacman, a cutting tool can be also located 1/2" above the corner. 
Similar to a v-block, the Pacman has a relief groove cut at the apex of the angle. Of course, the V is cut to ensure the apex of the 90 degree angle coincides with the axis of the cylinder.Other Pacmen could be made for angles other than 90 degrees. Maybe you envision other uses for the Pacman.
Thanks Dave!
