Get a compass (or some device you can use to draw circles with) and draw a circle with a radius of 5" from the pin (for a 5" pin to PAP distance.) Then do the same from the pre-drilling CG. The circles will intersect at two points. The intersection will represent where your PAP should be (you'll have to pick the correct intersection of the two for the drilling you are trying to achieve!) From the intersection point, use a quarter scale to draw in your vertical and horizontal axis values. The finishing position will be the center of your grip, which will put your PAP at 5" from the pin, as well as 5" from the CG. This method works for any "A x B" type drilling, where "A" is the pin to PAP distance, and "B" is the CG to PAP distance.
There's an easier way to map the special circumstance of an "A x A" drilling. First, draw a line going through the pin and CG. Then draw a perpendicular bisector line PB to this line. Now draw a line of length A from either the pin or CG to PB. Where this line intersects PB is your axis point. Follow the instructions above to find the center of your grip. Based on your PAP, this mapping will give you a pin-PAP and CG-PAP drilling of length A. Handy for those 3.375" x 3.375" max leverage drills.
Edited on 8/16/2004 7:33 PM
