Here’s a fast, accurate method that I use for locating the centerpoints for door latch and dead-bolt mortises. First I center a hole for a 6d nail in the end of a short piece of dowel (a 1-in. dia. dowel for a typical lockset). Then I drive the nail partway into the hole, cut it off and sharpen the remaining shank to a point.
After boring the holes for the lockset in the door’s stile, I insert the dowel into the hole that will contain the latch tube, as shown in the drawing. Then I close the door, and simply push the dowel marker toward the jamb. The sharpened nail marks the exact centerpoint for my latch or bolt hole.
Bernard H. King, Mechanicville, NY
