Proportional calipers assist you in reducing, or enlarging, the size of an object when carving from a template or a real-life object. If you are enlarging, set the pivot point to the desired ratio. Place the points on the short end of the calipers on the area of interest of the object to be replicated and tighten the wing nut. The long ends of the yard stick are now set to a proportionally larger size. As long as you keep the pivot point in the same spot, the ratio of the two ends will be the same every time.
Stack the two wood yardsticks with the measurement sides facing up and running in the same direction. Secure a large binder clip to the middle of the yardsticks to hold them in place.
Draw lines across the top yardstick at these measurements and label the lines "2:1" at 23 3/4 inches, "3:1" at 26 5/8 inches, "4:1" at 28 1/2 inches and "5:1" at 29 3/4 inches.
Draw a line down the middle of the long side of the yardstick.
Where the long line crosses the lines you drew across the yardstick, at the various distances, drill a hole with a 3/16-inch bit.
Saw a point at the ends of the stacked yardsticks using the miter saw. Repeat for the other ends of the stacked yardsticks.
Thread the bolt through the washer, through any hole on the yardsticks, through the second washer and screw on the wing nut.
Make the points are as close to the exact center of the yardstick as possible for accurate measurements.
Tie back hair and secure any loose clothing before using a drill.