A method for machining a groove in a sealing member and the edges of the groove. A tool 24 is formed with a top portion 24 having cutter sections 23A, each defining a cutting edge 23 for machining a groove in a scroll wall of a scroll member, and a tapered part 25 having cutter sections 26A, each defining a cutting edge 26 for bevelling the edges of the groove and the edges of the scroll wall. The groove 9 and edges 11 are simultaneously machined.
