Moe - imagine taking a perfectly white ball and rolling it straight through some wet paint on a flat surface. The result would be a red line on the ball where the surface of the ball contacted the paint. This red line represents your track.
Now imagine the same ball with the red line intact. Consider sticking a pole completely through the ball so that, when you roll the ball straight through the paint again: 1) the ball will roll on the same line you've already made on the ball and 2) the pole sticking through the ball will not "wobble" ... in other words as the ball with the pole stuck through it rolls straight through the paint, the pole will be sticking straight out to either side, parallel to the surface of the paint. The pole represents your rotational axis. The axis points (there are two) are the points on both sides of the ball where the pole exits/enters the surface of the ball.
With a bowling ball, the pole is imaginary, but your rotational axis does exist. Your axis points are the two points, one on each side of your track, that are the same distance from all points on your track. In general, layman's terms: If you're a right hander and you hook the ball to the left (in other words, you don't throw a backup ball), when you look at the ball with the fingers above the thumb, your positive axis point (PAP) will be to the right of the track. Flip that for lefties. In more technical terms, the positive axis point is the axis point closer to the track. You'll need a low- or non-flaring ball thrown normally through some oil to easily find your axis points. Your ball driller should be able to help here.
Axis tilt (not rotation) determines the size and "height" of your track. If you take the ball above with the pole through it - you can keep the pole parallel to the surface of the paint and turn it in any fashion. As long as the pole remains parallel to the surface as the ball rolls through the paint, you'll get the same track. Another way to think about tilt versus rotation is to think about the front wheels on a car. You can turn the wheels to make the car turn, but the wheels stay up-and-down in relation to the pavement (and a pole stuck through them would be parallel to the street surface). The only way to achieve tilt would be to get the car up on two wheels.
Consider a perfectly green ball (without any pole) and spinning it like a top in the paint. You would end up with a red circle on the bottom of the ball. Now your rotational (the pole) has been tilted to be perpendicular (standing straight up-and-down) to the the surface of the paint. The end result is that the pole is standing straight up and down and your PAP is touching the surface of the paint.
Most bowlers that throw a hook are between the two extremes (white ball versus green ball). The ball is thrown so that the pole (rotational axis) is actually thrown at an angle to the surface of the lane. The more angle, the more tilt and the "lower" the track (in relation to the finger holes). The less angle (the more parallel to the lane surface) the less tilt and the "higher" the track.
Hope this helps
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Kill the back row (or maybe this should read "make your spares, dummy")
Edited on 1/12/2005 1:26 PM
