Manufacture of turbine and compressor blades

Claim 1

THE METHOD OF FORMING A PASSAGEWAY IN A METAL PART BY ELECTRIC ARC DISINTEGRATION COMPRISING THE STEPS OF RELATIVELY RECIPROCATING SAID PART GENERALLY AXIALLY AND A HOLLOW ELECTRICALLY CONDUCTING TUBE SIZED AND SHAPED IN ACCORDANCE WITH THE PASSAGEWAY REQUIREMENTS, CONNECTING THE TUBE AND THE PART IN A DIRECT CURRENT ELECTRIC CIRCUIT, ADVANCING SAID TUBE AT SUCH A RATE AS TO CAUSE THE TUBE AND PART TO APPROACH WITHOUT TOUCHING SUFFICIENTLY CLOSE TO EFFECT ARCING ONLY BETWEEN THE TUBE TIP AND THE BOTTOM OF THE PASSAGEWAY AT EACH RECIPROCATION AS THE PASSAGEWAY IS FORMED AND FLOWING A STREAM OF ELECTROLYTE THROUGH THE HOLLOW TUBE, SAID ELECTROLYTE HAVING LOW CONDUCTIVITY AND BEING CAPABLE OF BREAK-DOWN AT THE VOLTAGE OF SAID CURRENT AT THE NEAREST APPROACH OF THE TUBE END AND PASSAGEWAY BOTTOM, SAID TUBE BEING HELICAL, AND A TWISTING ACTION BEING PRODUCED BETWEEN IT AND THE PART DURING THE RECIPROCATING AND ADVANCING OPERATIONS.

Claim 2

THE METHOD OF FORMING A PASSAGEWAY IN A METAL PART BY ELECTRIC ARC DISINTEGRATION COMPRISING THE STEPS OF RELATIVELY RECIPROCATING SAID PART GENERALLY AXIALLY AND A HOLLOW ELECTRICALLY CONDUCTING TUBE SIZED AND SHAPED IN ACCORDANCE WITH THE PASSAGEWAY REQUIREMENTS, CONNECTING THE TUBE AND THE PART IN A DIRECT CURRENT ELECTRIC CIRCUIT, ADVANCING SAID TUBE AT SUCH A RATE AS TO CAUSE THE TUBE AND PART TO APPROACH WITHOUT TOUCHING SUFFICIENTLY CLOSE TO EFFECT ARCING ONLY BETWEEN THE TUBE TIP AND THE BOTTOM OF THE PASSAGEWAY AT EACH RECIPROCATION AS THE PASSAGEWAY IS FORMED AND FLOWING A STREAM OF ELECTROLYTE THROUGH THE HOLLOW TUBE, SAID ELECTROLYTE HAVING LOW CONDUCTIVITY AND BEING CAPABLE OF BREAK-DOWN AT THE VOLTAGE OF SAID CURRENT AT THE NEAREST APPROACH OF THE TUBE END AND PASSAGEWAY BOTTOM, SAID TUBE BEING HELICAL, AND A TWISTING ACTION BEING PRODUCED BETWEEN IT AND THE PART DURING THE RECIPROCATING AND ADVANCING OPERATIONS.