An apparatus and method for separately boring precisely aligned opposing screw holes in individual frame members to be matingly joined at a miter joint. The apparatus comprises a first boring means for boring a first screw hole in the first frame member, a second boring means for boring a pilot screw hole in the second frame member, a carriage assembly on which the boring means are mounted and positioned relative to the miter-cut ends of the frame so that the separately bored first and pilot screw holes share a common centerline; and, a positioning means for supporting and precisely positioning the miter-cut end of the frame member in a repetitively consistent location to ensure that the first and pilot screw holes are identically located and aligned on each of the bored first and second frame members.