Abstract: In the present invention, a two-stage integral epitrochoidal cyclic rotor is produced by a machining method which produces the desired tolerences in both stages of the rotor without removing the work-piece from the support that holds it throughout the manufacturing process. In the manufacturing process, the blank starting work-piece, which is preferably a circular disc, is secured to a support element, for example by a magnetic chuck. The overall outer surface of the work-piece is then rotated and orbited while it is accurately machined to produce the epitrochoidal contour of the first stage of the rotor. Then, without releasing the work-piece from the holding surface, a second accurate machining operation, again with rotation and orbiting, is carried out on the upper half of the work-piece to form the epitrochoidal contour of the second stage of the rotor.