Dual Angle Sweet Spot

This article aims to assist in coming up with the "sweet spot" of dual angle specs, given a particular bowler's style. The final layout should always take into consideration the bowler, specific bowling ball, lane conditions, and the intended ball reaction.

Bowler Specs Affecting Dual Angle Sweet Spot

• Ball speed
• Rev rate
• Axis tilt
• Axis rotation

Dual Angle Ranges

Angle Sum

Angle sum is the sum of the drilling and VAL angles. The main components that will affect this are ball speed and rev rate. An example of a well matched bowler would be 18mph speed and 300rpm (off the hand). For each 1mph increase or decrease in speed, a corresponding increase or decrease of about 50rpm would stay matched. Bowlers whose ball speed and rev rate are well matched will match up best with angle sums of 100° ± 30°. In general, the ± 30° will stay the same, and the 100° will shift. For bowlers that are speed dominant, you would want to lower the center of the range, to a minimum of 60° ± 30°. For bowlers who are rev dominant, you would want to raise the center of the range, up to a maximum of 130° ± 30°.

Pin-PAP Distance

Note that the following ranges refer to asymmetrical cores, which have different properties at longer pin-PAP distances than do symmetrical cores. Bowlers with medium tilt will match up best with pin-PAP distances in the 4-5" range. Bowlers with higher tilt would want to use slightly longer distances, while bowlers with lower tilt would want to use shorter pin-PAP distances.

Angle Ratio

Angle ratio is the ratio of drilling angle to VAL angle. Acceptable ratios range from 1:3 to 3:1. The range used by a bowler is dependent on axis tilt and axis rotation. The more axis tilt and/or axis rotation a bowler has, the lower the angle ratios the bowler should use. A bowler with 30° degrees of axis rotation and 15° of axis tilt would do best between 1:1 and 2:1. A bowler with higher axis rotation and lower tilt, such as Pete Weber (generally around 60-75° axis rotation, and < 10° axis tilt), would do best between 1:3 and 1:1.

Of course, the range of Dual Angle specs that match for a bowler is only a guide. You must still determine what sort of reaction the bowler is looking to get out of the ball, and the condition that the bowler will be bowling on, in order to determine the ball and specific layout that will provide the best result. In order to determine where in the sweet range a layout should fit, please refer to the Dual Angle layout guide.

Mo On Ratios:

Ratio of angles are mainly a function of axis tilt and axis rotation (with tilt being somewhat more important than rotation).
This bigger the ratio (3:1), later and sharper the break point and the better it works for low tilt players (<12* of axis tilt). 
Conversely the smaller the ratio (1:2), the earlier and more forward rolling the break point and the better it works from high tilt players 
(>19* of axis tilt). With your tilt, I like a ratio of ~3:2 or 60/45. Once you decide on the ratio, the rest is math.

Other Literature

Sweet Spot Guide & Examples

Sources

• http://www.morichbowling.com/Drilling/DualAngleSeminar/DualAngleSeminar.htm
• http://forum.bowlingchat.net/viewtopic.php?p=2338#p2338
• http://forum.bowlingchat.net/viewtopic.php?p=1135#p1135
• The brains of Mo Pinel, Paul Ridenour, and Steve Freshour