Abstract: A method for manufacturing a dynamoelectric machine comprises the steps of manufacturing a magnetic frame of polygonal cross section by welding together at their respective ends a plurality of sides, some of which may include projections so that a required portion on each side is transected by the circumference of a circle or cylindrical plane of a radius of curvature equal to the distance between the longitudinally central axis of the dynamoelectric machine and a field device magnetic core mounting surface, of circularly machining the required portions on each internal face of the magnetic frame along the circumference of the aforementioned circle or cylindrical plane which transects the required portion on each side to form field device magnetic core mounting surfaces, of mounting field devices, either main pole field devices or interpole field devices, each comprising a magnetic core surrounded by a coil, on said field device magnetic core mounting surfaces, and of axially rotatably mounting an armature ax