To easily and precisely install a slider obtained by cutting from a belt-like plate, at a predetermined position on a substrate for a rotary electronic component.

The slider 50 coupled to the belt-like plate 90 through a coupling portion 95, the substrate 10 for the rotary electronic component and a terminal plate 30, and a die 110 and a punch 130 are prepared. The die 110 has a punch insertion hole 111, and the punch 130 has a blade 131. The punch insertion hole 111 is provided with a projection 117, and the blade 131 is provided with a recess 133 which engages the projection 117. The punch insertion hole 111, slider 50, and punch 130 are arranged in this order on the substrate 10 for the rotary electronic component; and the punch 130 is lowered to be inserted into the punch insertion hole 111 via the slider 50, so that the coupling portion 95 is cut with the punch insertion hole 111 and blade 131 and at the same time, the slider 50 separated from the belt-like plate 90 is lowered while guided by the projection 117 to be arranged on the substrate 10 for the rotary electronic component.