PURPOSE: To control play after fastening and to form a satisfactory appearance by deforming a rivet having the head and a deformed trunk part, and a washer passing through an orifice of the same volume as that of the end part where the trunk part is passed at most by a rivet driving machine until the trunk part blocks up the orifice.

CONSTITUTION: When a rivet 1 and a washer 2 are installed, the axial pressure is applied to the rivet. Especially by using a rivet driving machine, pressure is applied to the head 3 of the rivet 1 and the end of a trunk part by a vibrating projecting part to press until the end of the trunk part 4 blocks up the inner cylinders 11, 12 of the washer 2. Thus, free rotation is ensured for a small- diameter part 7 to be assembled and the height of a first cylinder 5 of the trunk 4 of the rivet 1 is larger than the thickness of the part 7 to be assembled, so that play between the parts 7, 10 to be assembled can be accurately adjusted by accurately selecting the height of the first cylinder 5.