The method involves mounting an inner segment (3) i.e. rotor segment, at an outer segment (2) i.e. stator segment, by fixing elements (6) such that segment modules (1) are formed. A preset air gap (5) is formed between the segments that are formed as annular segments and attached to a rotor or a stator of an electric machine. The inner segment is fastened to an inner assembly unit i.e. hub, so that the modules form a complete ring. The outer segment is fastened to an outer assembly unit i.e. support structure. The fixing elements between the inner and outer segments are removed.
