Patent ID: 7216438

Claim:
A method for finding the center of a straight side of a substantially rectangular workpiece comprising: aligning a first straight edge of a first side of a ruler with the straight side of the substantially rectangular workpiece; positioning a second straight edge of the ruler at an approximate center of the straight side; measuring a minimum distance from a first end of the straight side to the second edge of the ruler; marking a first line of an “X” using the second straight edge as a drawing guide; flipping the ruler over to a second side of the ruler; aligning the first straight edge of the ruler with the straight side; measuring the afore-determined minimum distance from a second end of the straight side to the second straight edge of the ruler; and making a second line of an “X” using the second straight edge as the drawing guide, wherein the center of the “X” marks the center of the substantially rectangular workpiece, and the first straight edge and the second straight edge define an angle θ.