A manufacturing tool for finishing a preformed scroll for use in a scroll type fluid displacement apparatus is disclosed. The tool includes a working member having an end plate and a first involute element extending from one end surface of said end plate. A cutting edge extends along the inner side wall of an axial end of the first involute, and the end plate has a plurality of arc shaped holes along the outer side wall of the first involute element. A second involute element is rotatably coupled to the working member and interfits with the first involute element in a disposition to define a radial gap between the first and second involute elements. A cutting edge extends along the outer side wall of a first axial end of the second involute. A plurality of pins project axially from the other axial end of the second involute element and penetrate through the arc shaped holes. A rotatable member has a plurality of holes extending in the axial direction. The pins have axial end portions which extend into the holes in the rotatable member to couple the rotatable member to the second involute member and to transmit the rotation of the rotatable member to the second involute element so that the relative rotation between the first and second involute elements adjusts the gap between them.