Method of making ducted panelling

Claim 1

THE PROCESS OF MANUFACTURING A DUCTED PANEL WHICH IS FABRICATED FROM A WELDED ASSEMBLY OF THREE LAYERS OF METAL INCLUDING A FIRST FERROUS METAL BASE MEMBER OF SUBSTANTIALLY RIGIDITY WHICH COMPRISES THE MAJOR THICKNESS OF SAID ASSEMBLY, A SECOND METAL LAYER IN ABUTMENT WITH A SURFACE OF SAID BASE MEMBER AND MADE OF A NON-FERROUS METAL, AND A THIRD NON-FERROUS METAL ABUTTING THE OUTER SURFACE OF SAID SECOND METAL CHAMBER, SAID PROCESS COMPRISING HEATING SAID FIRST BASE METAL TO A TEMPERATURE NEAR THE MELTING POINT OF THE MATERIAL OF SAID METAL COMPRISING SAID SECOND LAYER, APPLYING SAID METAL SECOND LAYER TO SAID FIRST FERROUS METAL BASE WHILE AT SAID TEMPERATURE AND MOLECULARLY WELDING THE TWO METALS TOGETHER, ABUTTING SAID THIRD LAYER OF NON-FERROUS METAL TO THE OUTER SURFACE OF SAID SECOND NON-FERROUS METAL LAYER AFTER APPLYING A STOPWELD MATERIAL ARRANGED IN A STRIP-PATTERN APPLIED BETWEEN THE TWO SURFACES, PRESSURE WELDING THE TWO LAYERS OF NONFERROUS METAL TOGETHER SAVE IN THE AREA THEREBETWEEN BOUNDED BY SAID STOP-WELD MATERIAL WHICH PROVIDES A CONTINUOUS PASSAGEWAY BETWEEN THE TWO, PROVIDING AN OPENING BETWEEN THE NON-FERROUS LAYERS TO SAID PASSAGEWAY, FASTENING A FLUID CONNECTION TO SAID OPENING, AND APPLYING SUFFICIENT FLUID PRESSURE THRU SAID FLUID CONNECTION TO SEPARATE AND MOVE APART ONLY THAT PORTION OF THE OUTER SHEET OF NON-FERROUS METAL ADJACENT SAID PASSAGEWAY TO ENLARGE SAID PASSAGEWAY, THE MATERIAL ADJACENT SAID PASSAGEWAY OF THE SECOND LAYER WELDED TO SAID FERROUS METAL BASE MEMBER BEING PREVENTED FROM DEFORMATION BY SAID BASE MEMBER WHICH RETAINS ITS SHAPE DURING THE APPLICATION OF SAID FLUID PRESSURE.