A. The effect clearance
Clearance c is the space (per side )between the punch and the die tool and die producers enjoy some kind of mystique related to their work as being both an art and science proper clearance between cutting edges enable fractures to start ideally at cutting edge of the punch and also at the die. The fracture will proceed towards each other until they meet and the fractured portion of the sheared edge then has a clean appearance. For optimum finish of a cut edge, correct clearance is necessary and is function of the kind, thickness, and temper of the material.