best way is to make a corner jig with a hole in the top where the drill is supposed to go . this way it is perfect every time . I took wood working shop in school for 6 years. Thts how I was taught
D'oh I shoulda been able to figure that out lol. Guess squinting at things on my phone isn't always the bestI found some rubber tips that fit on the all-thread. They were called rubber chair leg tips or something like that.