Abstract: Method and apparatus for engraving a surface by a rotating tool movable along X, Y and Z axes under computer control. The tool projects through a slit in a housing, the slit having a height greater than that of the characters to be engraved and a length longer than the series of characters to be engraved. Mechanical structure is contained in the housing to drive the tool along X and Y axes for forming the characters and along a Z axis to engage the work. The beginning and end of the engraving operation as well as character size and sequence are all controlled by a computer.