A system for creating a substantially planar face in a substrate, the system including directing one or more beams at a first surface of a substrate to remove material from a first location, the beam being offset from a normal to the first surface by a curtaining angle; sweeping the one or more beams in a plane that is perpendicular to the first surface to mill one or more initial cuts, the initial cuts exposing a second surface that is substantially perpendicular to the first surface; rotating the substrate about an axis other than an axis normal to the first beam or parallel to the first beam; directing the first beam at the second surface to remove additional material from the substrate without changing the curtaining angle; and scanning the one or more beams in across the second surface to mill one or more finishing cuts.