Finding the Positive Axis Point
Image shown for right-hander. Left-hander is reversed.
All drill patterns for bowling balls are customized for each individual bowler by starting with the bowler's Positive Axis Point (PAP). The positive axis point is the point on the ball that the ball initially rotates about. It can be found by finding the point on the ball that is equal distance from the bowler's initial ball track (before the ball flares). This is the first oil ring on the ball and is the one closest to the thumbhole. For a 3/4 roller (Ball track just outside of the fingers and thumb), the PAP is approximately 5" over along the midline and 1/2" up along the vertical axis line. This can be verified by placing a piece of tape on the ball at the PAP. Have a friend observe your bowling.
When the Ball First Comes off your hand and contacts the lane, the Tape Should Spin without moving around the ball. It should appear stationary if it is on the PAP. Some adjustments might be necessary. A bowler can't see this themselves. By the time they see the ball 10-12 feet past the foul line, the axis point has moved towards the preferred spin axis of the ball and they would get a false reading. A pro shop can find the PAP from the worn ball track on a ball, but the best method is the one suggested here. Once the PAP is determined, it is time to select a drilling pattern to create the ball reaction the bowler desires.
Describing Ball Motion
Image shown for right-hander. Left-hander is reversed
Drilling Patterns are techniques used to change the initial position of the core in the ball to alter its flare potential and distance it travels down the lane before it starts to hook. Generally, more flare is equated to more hook because it increases the friction. This is achieved by keeping a dry area of the ball in contact with the lane as opposed to an area of the ball, which has oil on the surface. The ball below shows the flare potential and ball reaction.
The Pin is the end of the core. By locating it at different distances from the PAP, we can create different ball motions in the same type of ball. The center of gravity (CG) is the heaviest point on the ball. Moving it to different locations has the same effect as moving the pin, but it has less impact. For example, if a ball is drilled with the pin at 3" and the CG at 1" from the PAP, it will have maximum flare from the pin position. It will also start hooking earlier with an arcing break point due to the CG position.
Label Drilling
CG to PAP Distance:near center of grip with 1/2oz. Positive Wt.
CG to PAP Distance:near center of grip with 1/2oz. Positive Wt.
CG to PAP Distance:near center of grip with 1/2oz. Positive Wt.
Results: Will reduce the flip on the backend creating a strong arcing backend and an average distance to the break point.
Preferred Lane Conditions: Fresh lane conditions with oily heads and dry to medium backends. Will not over react on the backend.
Drawbacks: Looses hitting power as the shot moves in deep because it does not have a strong backend flip.
Extended Length with Strong Arc Drilling
CG to PAP Distance:3 3/8"
CG to PAP Distance:4"
CG to PAP Distance:5"
Results: Minimum track flare to reduce the friction and get the ball further down the lane creating the latest break point. Bowlers with early rolling styles (12-15) will like the extra length.
Drawbacks: May want to go too long and not flip enough on carrydown, especially for bowlers with Skid Styles(4-7).
CAUTION- a pin shift of more than 6 3/4" will cause the track to flare in the wrong direction (it will flare towards the thumb hole instead of away). Therefore, use caution when drilling 6" and 6 1/2" pin shift to insure the pin to the PAP Distance is correct.
Early Roll with Arc Drilling
CG to PAP Distance:0 to 1 1/2"
CG to PAP Distance:2"
CG to PAP Distance:2"
Results: Arcing ball path. Will start hooking in oil, which will reduce the flipping motion at the break point. This will require a dry backend to allow the ball to finish.
Preferred Lane Conditions: Best for oily heads with dry borads somewhere (I.E. down the lane or outside).
Drawbacks: Carrydown on the backends will reduce hitting power.
Early Hook with Flip Drilling
CG to PAP Distance:3 3/8"
CG to PAP Distance:4"
CG to PAP Distance:4 1/2"
Results: Creates track flare to give a maximum friciton between the ball and the lane. Results in an early break point and sharp turn.
Preferred Lane Conditions: Best for oily lane conditions with and without carrydown.
Drawbacks: Can use up friction early resulting in an early hook out. Bowlers with an Early Roll Style (12-15) may have their break point happen to early.
Determining Bowler Style
Bowler's Style: Determine the numerical value. Select the property in each row that best describes the bowler and record the numerical value in the parenthesis (). Then add up the total and check the sum with the Total at the bottom of the chart.
| Skid Properties | Medium Properties | Early Roll Properties | |
| Rotation | Low < 230 RPM <14 revolutions (1) |
Average 230-270 RPM -14-16 revolutions (3) |
High(Cranker) 270+ RPM -17+ revolutions (5) |
| Speed | Fast 19+ MPH (1) |
Average 17-18 MPH (2) |
Slow < 17 MPH (3) |
| Axis of Rotation | 60-90 degrees (1) |
30-60 degrees (2) |
0-30 degrees (4) |
| Axis Tilt | Spinner (1) |
Low 3/4 Roller (2) |
High-track; full-roller and track close to finger and thumb (3) |
| Total | 4 - 7 (Skid Style) Style causes ball to go long. |
8 - 11 (Average Style) Style causes a medium break |
12-15 (Early Roll Style) Style causes ball to start rolling early. |
Based on bowler's total:
A Total of between 4-7 is a Skid Style: Which results in a ball path with a lot of skid and a late break point. Therefore, earlier rolling drilling patterns are recommended.
A Total between 8-11 is an Average Style: That results in a ball path with an average breakpoint
A Total Between 12-15 is an Early Roll Style: That results in a ball path that will roll early and have an early break point. Therefore, drilling patterns that delay the hook are recommended.
