PURPOSE: To reduce the cost of a product by splining cup-shaped members worked from a blanked billet and sintering sinterable alloy powder to a base body joined symmetrically with a pair of such members to form a cam part.

CONSTITUTION: The billet is deep-drawn and is made into the cup-shaped member 2 and detaining parts 3 having the spline pattern are formed thereto. A pair of such mated members 2 are set symmetrical to the center line and are then partially welded to obtain the base body 4 having a cam profile. The sinterable powder alloy is packed into the space between a cylindrical body 5 of a tool and the body 4 and is pressurized by a plunger puch to form a powder molding 6a which is then sintered. The completed cam part is press-fitted into a separately worked cam shaft part 10 and is fixed by a pin 12. The cam body is then welded, set and unitized by a weld zone 14 to the shaft body 10. Assembling errors are decreased by the above-mentioned method, by which the man-hour for manufacture is considerably reduced and the cost is reduced.