A method for manufacturing an adaptive stage for a turbine including a rotatable swivel ring and a stationary integral collar, the method comprising the steps of: - manufacturing a plurality of blades, each blade including a pressure side and a suction side extending from a leading edge to a trailing edge, - fixing each blade to an inner blade ring (31, 32) and an outer blade ring (41, 42), in order that the leading edge and the trailing edge extend from one to the other of the inner blade ring (31, 32) and the outer blade ring (41, 42), characterized in that the method further comprises the steps of: - fixing a first cover ring and a second cover ring between the inner blade ring (31, 32) and the outer blade ring (41, 42), the inner blade ring (31, 32) and the outer blade ring (41, 42) being interposed between the first cover ring and the second cover ring, - cutting the assembly of blades, the inner blade ring (31, 32), outer blade ring (41, 42), first cover ring and second cover ring along a plane intermediate between the first cover ring and second cover ring, in order to: - separate each blade into a leading portion including the leading edge and a trailing portion including the trailing edge, - separate the inner blade ring (31, 32) into a first inner blade ring and a second inner blade ring, - separate the outer blade ring (41, 42) into a first outer blade ring and a second outer blade ring, the leading portions extending between the first inner blade ring and the first outer blade ring and the trailing portions extending between the second inner blade ring and the second outer blade ring - removing the first cover ring and the second cover ring, from the inner blade rings (31, 32) and the outer blade rings (41, 42). - manufacturing a plurality of blades, each blade including a pressure side and a suction side extending from a leading edge to a trailing edge, - fixing each blade to an inner blade ring (31, 32) and an outer blade ring (41, 42), in order that the leading edge and the trailing edge extend from one to the other of the inner blade ring (31, 32) and the outer blade ring (41, 42), - fixing a first cover ring and a second cover ring between the inner blade ring (31, 32) and the outer blade ring (41, 42), the inner blade ring (31, 32) and the outer blade ring (41, 42) being interposed between the first cover ring and the second cover ring, - cutting the assembly of blades, the inner blade ring (31, 32), outer blade ring (41, 42), first cover ring and second cover ring along a plane intermediate between the first cover ring and second cover ring, in order to: - separate each blade into a leading portion including the leading edge and a trailing portion including the trailing edge, - separate the inner blade ring (31, 32) into a first inner blade ring and a second inner blade ring, - separate the outer blade ring (41, 42) into a first outer blade ring and a second outer blade ring, the leading portions extending between the first inner blade ring and the first outer blade ring and the trailing portions extending between the second inner blade ring and the second outer blade ring - separate each blade into a leading portion including the leading edge and a trailing portion including the trailing edge, - separate the inner blade ring (31, 32) into a first inner blade ring and a second inner blade ring, - separate the outer blade ring (41, 42) into a first outer blade ring and a second outer blade ring, the leading portions extending between the first inner blade ring and the first outer blade ring and the trailing portions extending between the second inner blade ring and the second outer blade ring - removing the first cover ring and the second cover ring, from the inner blade rings (31, 32) and the outer blade rings (41, 42).