Disclosed herein is a method of crimping a prosthetic heart valve using a compact crimping mechanism. The crimping mechanism includes a plurality of jaws configured for coordinated inward movement toward a crimping axis to reduce the size of a crimping iris around a stented valve. A rotating cam wheel acts on the jaws and displaces them inward. An actuation mechanism includes a lead screw, carriage assembly and a linkage to rotate the cam wheel with significant torque.