MACHINE ENGRAVING Computerised Diamond Drag Engraving: AKA Scratch This computerised method of engraving is recommended for softer metal such as gold and silver, pewter-ware, aluminium and brass. It is most extensively used for trophies, awards and gift ware. This method uses a non-rotating instrument with a pointed sharp tip, That is drawn with pressure through the metal, leaving an incision. Diamond-drag obtains results that are consistent in size and don't vary in depth. This is a very fast cost effective procedure that is used on a variety of items.