Built up nonmetallic wave guide having metallic coating extending into corner joint and method of making same

Claim 1

A METHOD OF FABRICATING A WAVE GUIDE, INCLUDING THE FOLLOWING STEPS: PREPARING A SHEET OF NON-METALLIC MATERIAL WITH A FLAT FACE; APPLYING TO SAID FLAT FACE A METALLIC UNDERCOATING HAVING A SMOOTH EXPOSED SURFACE; BRIGHT-PLATING A SURFACE COATING OF NOBLE METAL ON SAID UNDERCOATING TO PROVIDE AN INTERNAL METAL COATING HAVING A FINISH SURFACE OF A HIGH DEGREE OF SMOOTHNESS; PROVIDING IN SAID SHEET OF NON-METALLIC MATERIAL A PLURALITY OF LATERALLY SPACED PARALLEL GROOVES EXTENDING FROM THE SIDE THEREOF OPPOSITE SAID METALLIC COATING TO A DEPTH CLOSELY ADJACENT SAID METALLIC COATING SO AS TO PROVIDE A PLURALITY OF SIDE PANELS JOINED BY THIN WEBS INCLUDING SAID METALLIC COATING, BENDING SAID THIN WEBS SO AS TO POSITION SAID PANELS IN THE FORM OF A POLYHEDRAL TUBE WITH SAID WEBS AS SEVERAL CORNERS THEREOF AND WITH EXTERNAL CORNER RECESSES DEFINED BETWEEN THE SIDE FACES OF SAID GROOVES; BRINGING FREE SIDE MARGINS OF THE LATERAL PANELS INTO ADJOINING RELATION TO FORM ANOTHER CORNER OF SAID TUBE; FILLING SAID CORNER RECESSES WITH NON-METALLIC MATERIAL BONDED TO SAID SIDE FACES OF SAID GROOVES TO REINFORCE THE FILLED CORNERS; JOINING SAID FREE MARGINS TO ONE ANOTHER TO CONSTITUTE SAID OTHER CORNER, WHEREBY TO FORM A CORNER JOINT; PROVIDING AT THE INNER EXTREMITY OF SAID CORNER JOINT A METALLIC JOINT INTEGRALLY JOINING THE COATINGS OF SAID ADJOINED PANELS; SAID FREE SIDE MARGINS BEING DEFINED BY MARGINAL FACES NORMAL TO THE SIDE FACES OF THE RESPECTIVE LATERAL PANELS AND DEFINING AN EXTERNAL 90 DEGREES CORNER RECESS IN SAID TUBE;AND INCLUDING THE FURTHER STEPS OF PROVIDING, AT SAID OTHER CORNER, EXTENSIONS OF SAID METALLIC COATING BEYOND SAID MARGINAL FACES IN THE FORM OF NARROW MARGINAL LIPS; BENDING SAID LIPS AT ACUTE DIHEDRAL ANGULAR RELATION TO SAID MARGINAL FACES; BRINGING THE BENT LIPS TOGETHER; PROVIDING A METALLIC BOND BETWEEN THE EXPOSED METALLIC FACES OF SAID LIPS; AND FILLING SAID EXTERNAL CORNER RECESS WITH A STRIP OF MATERIAL OF CHANNEL FORM BINDING SAID LIPS TO ONE ANOTHER AND BONDED TO SAID MARGINAL FACES TO REINFORCE SAID CORNER JOINT.

Claim 2

A METHOD OF FABRICATING A WAVE GUIDE, INCLUDING THE FOLLOWING STEPS: PREPARING A SHEET OF NON-METALLIC MATERIAL WITH A FLAT FACE; APPLYING TO SAID FLAT FACE A METALLIC UNDERCOATING HAVING A SMOOTH EXPOSED SURFACE; BRIGHT-PLATING A SURFACE COATING OF NOBLE METAL ON SAID UNDERCOATING TO PROVIDE AN INTERNAL METAL COATING HAVING A FINISH SURFACE OF A HIGH DEGREE OF SMOOTHNESS; PROVIDING IN SAID SHEET OF NON-METALLIC MATERIAL A PLURALITY OF LATERALLY SPACED PARALLEL GROOVES EXTENDING FROM THE SIDE THEREOF OPPOSITE SAID METALLIC COATING TO A DEPTH CLOSELY ADJACENT SAID METALLIC COATING SO AS TO PROVIDE A PLURALITY OF SIDE PANELS JOINED BY THIN WEBS INCLUDING SAID METALLIC COATING, BENDING SAID THIN WEBS SO AS TO POSITION SAID PANELS IN THE FORM OF A POLYHEDRAL TUBE WITH SAID WEBS AS SEVERAL CORNERS THEREOF AND WITH EXTERNAL CORNER RECESSES DEFINED BETWEEN THE SIDE FACES OF SAID GROOVES; BRINGING FREE SIDE MARGINS OF THE LATERAL PANELS INTO ADJOINING RELATION TO FORM ANOTHER CORNER OF SAID TUBE; FILLING SAID CORNER RECESSES WITH NON-METALLIC MATERIAL BONDED TO SAID SIDE FACES OF SAID GROOVES TO REINFORCE THE FILLED CORNERS; JOINING SAID FREE MARGINS TO ONE ANOTHER TO CONSTITUTE SAID OTHER CORNER, WHEREBY TO FORM A CORNER JOINT; PROVIDING AT THE INNER EXTREMITY OF SAID CORNER JOINT A METALLIC JOINT INTEGRALLY JOINING THE COATINGS OF SAID ADJOINED PANELS; SAID FREE SIDE MARGINS BEING DEFINED BY MARGINAL FACES NORMAL TO THE SIDE FACES OF THE RESPECTIVE LATERAL PANELS AND DEFINING AN EXTERNAL 90 DEGREES CORNER RECESS IN SAID TUBE;AND INCLUDING THE FURTHER STEPS OF PROVIDING, AT SAID OTHER CORNER, EXTENSIONS OF SAID METALLIC COATING BEYOND SAID MARGINAL FACES IN THE FORM OF NARROW MARGINAL LIPS; BENDING SAID LIPS AT ACUTE DIHEDRAL ANGULAR RELATION TO SAID MARGINAL FACES; BRINGING THE BENT LIPS TOGETHER; PROVIDING A METALLIC BOND BETWEEN THE EXPOSED METALLIC FACES OF SAID LIPS; AND FILLING SAID EXTERNAL CORNER RECESS WITH A STRIP OF MATERIAL OF CHANNEL FORM BINDING SAID LIPS TO ONE ANOTHER AND BONDED TO SAID MARGINAL FACES TO REINFORCE SAID CORNER JOINT.