Abstract: Gas separation nozzles are produced by machining the nozzle parts, such as a holding body and separation elements by moving sectional material, for example, prefabricated sectional steel or aluminum alloy rods through a high precision sliding guide path past a shaving tool, whereby the workpiece is pressed against supporting and retaining surfaces of the guide path at least at three points and a shaving tool is applied to the moving workpiece in an area defined by said three points so that the tool is effective as close as possible to the pressure applying points or areas. At least two separation elements are supported in a dovetail groove of a holding body so that nozzle edges of the elements extend into a gas deflection groove in the holding body. Where four separation elements are held in a common dovetail groove of the holding body, two of the four elements are provided with a gas deflection groove extending along its respective nozzle edge.