Method for manufacturing a magnet switch, said magnet switch comprising: a stationary core; a movable core; and a magnetic coil that, when excited, produces magnetic attraction through said stationary core to attract said movable core along a given travel path to one of open or close electric contacts; wherein said stationary core includes a disc assembly and a core body, the core body having opposed ends, a base, a boss, and an outer shoulder formed between the base and the boss, the base having an end that is one of the opposed ends and faces said movable core in an axial direction of the magnetic switch, the boss having an end that is the other of said opposed ends and is facing away from said movable core across the base in an axial direction of the magnetic switch and wherein the disc assembly consists of a stack of annular plate members superposed on each other in a thickness-wise direction thereof and has a fitting hole extending through a thickness of the stack, each of the annular plate members having a circular center hole, which defines the fitting hole of the disc assembly, the disc assembly being fit at the fitting hole on the boss; and wherein at least a portion of an edge of the end of the boss is plastically deformed outward in a radius direction of the boss to create an elastic nip which retains the stack of the annular plate members of the disc assembly between the edge and the outer shoulder of the core body; wherein a shear drop on the inner circumferential edge is formed on an annular plate member located outermost in the stack; wherein the stack of the punched annular plate members is mounted on the boss so that the annular plate member having the shear drop faces away from the base of the core body; the method being characterized in that, for forming said stack of annular plate members, the circular center holes are punched out in a stack of plate members in the thickness-wise direction thereof so that said shear drop is formed; and in that only a corner of the boss is deformed by elastically bending tabs or an annular ridge formed on the outer peripheral edge or corner of the boss outward in the radius direction of the boss into abutment with the rounded inner peripheral corner of the center hole of the sheet of the disc assembly, thereby exerting elastic pressure on the stack of the sheets so that the elastic pressure acts on the stack of the sheets both in the radially outward direction of the disc assembly and in a direction in which the stack of the sheets is pressed against the shoulder of the base, that is, compressed in the axial direction of the disc assembly. a stationary core; a movable core; and a magnetic coil that, when excited, produces magnetic attraction through said stationary core to attract said movable core along a given travel path to one of open or close electric contacts; wherein said stationary core includes a disc assembly and a core body, the core body having opposed ends, a base, a boss, and an outer shoulder formed between the base and the boss, the base having an end that is one of the opposed ends and faces said movable core in an axial direction of the magnetic switch, the boss having an end that is the other of said opposed ends and is facing away from said movable core across the base in an axial direction of the magnetic switch and wherein the disc assembly consists of a stack of annular plate members superposed on each other in a thickness-wise direction thereof and has a fitting hole extending through a thickness of the stack, each of the annular plate members having a circular center hole, which defines the fitting hole of the disc assembly, the disc assembly being fit at the fitting hole on the boss; and wherein at least a portion of an edge of the end of the boss is plastically deformed outward in a radius direction of the boss to create an elastic nip which retains the stack of the annular plate members of the disc assembly between the edge and the outer shoulder of the core body; wherein a shear drop on the inner circumferential edge is formed on an annular plate member located outermost in the stack; wherein the stack of the punched annular plate members is mounted on the boss so that the annular plate member having the shear drop faces away from the base of the core body; the method being characterized in that, for forming said stack of annular plate members, the circular center holes are punched out in a stack of plate members in the thickness-wise direction thereof so that said shear drop is formed; and in that only a corner of the boss is deformed by elastically bending tabs or an annular ridge formed on the outer peripheral edge or corner of the boss outward in the radius direction of the boss into abutment with the rounded inner peripheral corner of the center hole of the sheet of the disc assembly, thereby exerting elastic pressure on the stack of the sheets so that the elastic pressure acts on the stack of the sheets both in the radially outward direction of the disc assembly and in a direction in which the stack of the sheets is pressed against the shoulder of the base, that is, compressed in the axial direction of the disc assembly.