Page 119 - Demo

117GENERAL PURPOSE DRILLINGExchangeable Head Drills TroubleshootingDR-TWIST TroubleshootingChipping Along Cutting Edge1 Reduce entrance feed.2 Choose a tougher grade.3 Choose a geometry with open chip breaking for higher feeds. (SOMT, WOLH)4 Reduce feed.*5 Reduce cutting speed.6 Increase coolant pressure.Machine Troubleshooting Vibrations1 Check mounting of drill.2 Check mounting of workpiece.3 Increase feed. If drilling a very soft material, reduce feed and increase speed.*4 Reduce cutting speed.Chipping of Center Insert1 Check mounting of drill.2 Check mounting of workpiece.3 Reduce entrance feed.4 Reduce cutting speed.5 Check drill runout (should be 0.05 mm maximum).Insufficient Torque1 Reduce feed.*2 Choose a geometry with a looser chipformer.Excessive Flank Wear1 Reduce cutting speed.2 Increase coolant pressure/volume.3 Choose a better wear resistant grade.Insufficient Power1 Reduce cutting speed.2 Reduce feed.*3 Choose a geometry with a looser chipformer.