Pit cutter apparatus

Apparatus for accurately making an anomaly of predetermined size and depth in the surface of a standard for calibrating an instrument for non-destructive testing for such anomalies and indicating the severity thereof, comprising

• frame means elongated along its longitudinal axis;
• a pair of electro-magnetic hold-down means mounted on said frame means each having a laterally spaced pair of legs depending from said frame means for contacting the surface of the standard;
• one of said hold-down means being disposed adjacent the front end of said frame means and the other of said hold-down means being longitudinally spaced therefrom intermediate the ends of said frame means;
• motor means disposed between said hold-down means and having cutting means of predetermined size depending therefrom for making an anomaly in the surface of the standard when rotatably driven by said motor means;
• means movable relative to said frame means for mounting said motor means and moving said motor and cutting means toward and away from the surface of the standard;
• means adjacent the rear end of said frame means for manually moving said mounting means and having adjustable means for indicating when said cutting means has moved a predetermined depth into the standard;
• a pair of rotatable shafts journaled in said frame means each threadedly engaging a respective end region of said motor mounting means;
• means drivingly connecting said pair of rotatable shafts together;
• and
• means drivingly connecting said means adjacent the rear end of said frame means to one of said pair of shafts for manually rotating said pair of shafts in unison to move said motor mounting means relative to said frame means.