this shape of the spiraling part 241 b shown in fig8 in particular it is possible to increase the hardness of the portion 241 b 1 positioned in the external periphery of the spiral in the spiraling part 241 b in the method for manufacturing a fixed scroll 24 the shape shown in fig6 or 7 may be used for the spiraling part 241 b the following is a description of the orbiting scroll 26 obtained by either one of the manufacturing methods in the first and second embodiments as described in the first and second embodiments the compression member 26 b belonging to the orbiting scroll 26 obtained by the pertinent manufacturing methods i e the spiraling part 261 b after step b is performed has a high hardness consequently in the portion near the external periphery in the compression member 26 b the compression member 26 b does not readily deform even if the ratio h t of the height h of the compression member 26 b from the panel 26 a fig2 3 and 7 to the thickness t of the compression member 26 b fig2 3 and 7 is 8 5 or greater the orbiting scroll.