MACHINING METHOD FOR SCROLL SHAPE

PURPOSE:To sharply improve squareness of a scroll shape with a base surface by a method wherein flexural rigidity of the protrusion part of the scroll shape is set to approximately the same value as that of a machining tool. CONSTITUTION:A blade 3 in a scroll shape protruded from a base surface 2 at right angles is integrally formed to a scroll compressor 1 being a work. An end mill 4 applying finish machining on the inner and outer surfaces of the blade 3 is disposed in a direction extending at right angles with the base surface 2, and a flexural rigidity F1 of the end mill 4 is set to approximately the same value as flexural rigidity F2 in a direction extending at right angles with the base surface of the blade 3. When finish machining is applied on the side of the blade 3 by using the end mill 4, the scroll compressor 1 is mounted to a milling machine and a finish cutting work is effected in a state that the end mill 4 is pressed against the side of the blade 3. In this case, a bending amount of the blade 3 is offset with a bending amount of the end mill 4. As a result, squareness of the scroll shape with the base surface 2 is sharply improved.