Apparatus for method for etching objects

Claim 1

IN CATHODIC VACUUM ETCHING OF A RADIOACTIVE BODY, THE METHOD OF ESTABLISHING ELECTRICAL AND THERMAL CONTACT BETWEEN SAID RADIOACTIVE BODY AND A COOLED ELECTRICAL AND THERMAL CONDUCTOR HAVING A COOLING SURFACE OF SUBSTANTIAL AREA AND HAVING AN ELECTRIC POTENTIAL IMPRESSED THEREON, THE SAID METHOD COMPRISING MOUNTING SAID CONDUCTOR SO THAT SAID SURFACE IS AT THE PRESSURE WITHIN SAID ENCLOSURE AND ANOTHER SURFACE OF SAID CONDUCTOR IS AT ATMOSPHERIC PRESSURE, SAID CONDUCTOR BEING MOUNTED MOVABLE UNDER ANY DIFFERENCE IN PRESSURE BETWEEN SAID ENCLOSURE AND THE ATMOSPHERE, MECHANICALLY CLAMPING SAID BODY ADJACENT SAID SURFACE OF SAID CONDUCTOR ACTION OF A REMOTELY ACTUABLE MANIPULATOR, EXHAUSTING SAID CHAMBER TO ESTABLISH SAID DIFFERENCE OF PRESSURE, UNDER THE ACTION OF SAID PRESSURE DIFFERENCE CAUSING SAID CONDUCTOR TO MOVE TO ENGAGE SAID BODY AND TO APPLY SAID PRESSURE DIFFERENCE THERETO TO PROVIDE ELECTRICAL AND THERMAL CONTACT BETWEEN SAID CONDUCTOR AND SAID BODY.