Compound angle cutting edge and method of using same

In a method of cutting stock material, the steps of:

• positioning the stock material on a resilient die pad in alignment with a cutting die rule, said die rule having a chamfered portion defined by two converging surfaces which intersect to form a cutting portion, said cutting portion having formed thereon a plurality of notches which define a plurality of generally equally spaced piercing points and a plurality of substantially linear primary cutting edges extending from each piercing point substantially the entire distance to an adjacent piercing point, said primary cutting edges extending away from said piercing points by an angle of no more than fifteen degrees, thereby forming a valley on the cutting portion between each piercing point, said valley having a depth of no more than three sixteenths of an inch;
• relatively moving the stock material and the die rule toward one another, and in a substantially simultaneous, sequential operation (a) initially penetrating the stock material at a plurality of positions with the die rule piercing points, (b) cutting the stock material with the primary cutting edges in a direction away from each initially penetrated position toward a next adjacent penetrated position, whereby the stock material between each penetrated position is cut substantially the entire distance therebetween in a progressive cutting action in substantially only one direction at a rate of greater than 3.73 times the rate of relative movement between the stock material and the die rule, due to the angle of the primary cutting edges, and (c) pressing the piercing points through the stock material and into the resilient die pad by a distance of not more than about three sixteenths of an inch due to the shallow valley depth on the cutting portion, at which depth the stock material will be cut through its entire depth by the cutting edges;
• and
• retracting the stock material from the die rule and die pad.