Tool for machining festoons and attachment holes of a disc flange by PECM and method using this tool

Tooling for producing scallops and fastening holes of a clamp of a disc by electrochemical machining using an electrolyte, the tooling having: an annular support tray to receive the disc; lower and upper shields configured to protect the disc from splashes of the electrolyte; a clamping lock to hold the disc in position during machining; and a die-sinking tool having in a substantially cylindrical insulating body a first and a second coaxial conductive cathode, the first and second cathodes rigidly fastened to each other, the first annular cathode including at an external periphery a plurality of radial machining protrusions of a shape complementary to that of the scallops to be machined and the second cathode includes, on the same circumference external to the first cathode relative to the central axis of the disc, a plurality of axial machining nozzles of a shape similar to the fastening holes to be machined.