It’s amazing that no power tool manufacturer has designed a drill that makes it easy to create holes perfectly perpendicular to the surface of the workpiece. As Jimmy DiResta once suggested, the top and perhaps one side surface of hand drills ought be made perfectly flat, so folks could run it against a straightedge to get square results.
Until someone creates such a thing, here’s a trick for using the reflection in an old CD to help improve squareness:
Source: core77
