Disclosed is a heat sink manufacturing method including the steps of: determining at least one cutting line in one direction from one side point on the processing surface; individually deriving fin-specific forward and backward lengths of the skiving cutter according to the separation distance of the at least one cutting line separated from the one side point; separating, on the basis of the fin-specific forward and backward lengths, at least one auxiliary fin and one main fin from the object by sequentially moving the skiving cutter forward and backward along the at least one cutting line; and processing the one main fin so that same stands upright relative to a base plate on which the object is stacked, so as to manufacture a heat sink formed in the shape of a plurality of fins branching upward from the one main fin.

A pressed article includes a main body, a recess portion, a pin, and a groove portion. The main body has a plate shape. The recess portion is provided in a first surface of the main body facing one side in a plate thickness direction of the main body. The pin is provided at a position corresponding to the recess portion on a side of a second surface opposite to the first surface of the main body, is formed to have an outer shape smaller than that of the recess portion when viewed in the plate thickness direction of the main body, and protrudes in the plate thickness direction of the main body. The groove portion is recessed from the second surface of the main body toward the first surface and is provided to surround at least a part of the periphery of the pin.