| 摘要 |
A centering ruler includes a first straight edge, a second straight edge, an angle theta therebetween, and a measuring scale, marked on both sides of the ruler, which divides the first straight edge into equal increments. To find the center of a straight side of a workpiece, one aligns a first edge of a first side of a ruler with the straight side, positions a second edge of the ruler at the approximate center of the straight side, measures a minimum distance from a first end of the straight side to the second edge of the ruler, marks a first line of an "X" using the second edge as a guide, flips the ruler over to the second side, aligns the first edge of the ruler with the straight side, measures the afore-determined minimum distance from a second end of the straight side to the second edge of the ruler, and marks a second line of an "X" using the second edge as a guide. The center of the "X" marks the center of the workpiece.
|
