We are often asked if there is a jig for ensuring the drill used to hog out a drill for pegs is at a 90 degree angle. We have never seen a guide that really does the job but we use a mirror to ensure that drill bit is vertical. We have drilled a 7/8-in diameter hole through these plexi-glass mirrors, set your bit in the hole and watch the reflection to be sure you are not holding it at an angle.