- 1 Calculating a Benchmark Layout:
- 2 Finding Your Benchmark Total Sums
- 3 Find Your Benchmark Ratio primarily analyzing tilt and rotation
- 4 Ratio Discussion
- 5 Drilling and Val Angle Math Examples
- 6 Choosing Pin to PAP distances
- 7 Roll the ball, then use balance holes to fine tune reaction
Calculating a Benchmark Layout:
- ...Find bowler's specs.
- ball speed
- rev rate
- axis tilt
- ...Find Benchmark Total Sums.
- ...Find Benchmark Ratio.
- ...Choose a Pin to PAP distance
Finding Your Benchmark Total Sums
Step #1- Determine the Initial Sums of angles primarily analyzing bowler's ball speed & rev rate.
Start your calculations by finding the relationship between ball speed and rev rate. An example of a well matched bowler would be 17mph 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 who are speed/revs matched would start their calculations with 95* of sums. Link Text
Rules of thumb:
- For the first 50 revs of imbalance (in excess), add 10* to the Total Sums.
- For the first 1 mph of speed imbalance (in excess), subtract 10* from the Total Sums.
If the speed/revs imbalance is extremely high or low, you would add or subtract extra sums to compensate accordingly. The amount of sums you add or subtract is not linear (for the second 50 revs of imbalance, you will add or subtract less than 10*, etc.)
Step #2-Adjust Initial Sums (of step #2) for very high or very low tilt & rotation.
Mo will also lower the sum of angles for those with very high tilt & rotation, or raise the sum for those with very low tilt & rotation.
For tilt adjustments, we are using 13* to 17* of tilt as the normal tilt range.
For rotation adjustments, we are using 45* to 60* of rotation as the normal rotation range.
Rules of thumb:
- Lower totals by about 10° for high tilt
- Raise totals by about 10° for low tilt
- Lower totals by about 5° for high rotation
- Raise totals by about 5° for low rotation
If the tilt or rotation is extremely high or low, you could add or subtract extra sums to compensate accordingly.
Step #3-Determine your Total Sums Range (for symbiotic layouts matching your specs)
Total sums determines the length of ball motion until the roll phase (See: Three Phases of Ball Motion)
- Degree of drill angle + degree of val angle = Total Sums.
- Note: The total sums of your sweet spot will include a + or - degrees.
- ± 30° for elite bowlers
- ± 20° for good bowlers
- ± 10° for average bowlers
- Adding these degrees to your total sums will add length to the ball motion. (increasing total length of ball motion before reaching the roll phase)
- Subtracting these degrees from your total sums will decrease the length of ball motion.
Sweet spot of 100º (± 20º)
For dry or short oil patterns to increase' length, use 120º sums.
- Use a high ratio for long and strong layouts.
- Use a low ratio for control layouts.
For oily or longer patterns to decrease length, use 80º sums. (utilizing ratios to achieve the desired break shape)
- Use a high ratio for defined/sharp motion.
- Use a low ratio for mid-lane roll.
Find Your Benchmark Ratio primarily analyzing tilt and rotation
This is necessary to accurately calculate the drilling angle and the val angle individually.
- Find initial tilt ratio (see table below).
- Adjust this ratio higher or lower according to your axis rotation.
- Move box to left or right on chart. Extreme speed or rev dominance can accentuate this which requires more of an adjustment.
- If there is no (primary ) adjustment necessary for high or low rotation, you do not need to adjust for speed or rev dominance (secondary)
- Calculate the ratio range.
- This is necessary to mathematically calculate your personal desired ball motions/layouts. (control, long and hard, mid-lane, strong oil, etc.)
- For examples on how to do the math, see simple math examples.
Step #1-Find The Initial Ratio From Axis Tilt
The middle column (initial ratio benchmark range) gives approximate ratios for bowlers with speed/revs = matched + normal rotation.
Please note: when creating the chart we used 50º to 55º as normal axis rotation. (45º is slightly low and 60º is slightly high)
- For axis tilt below 7º (especially when accompanied by high rotation) use this PDF chart.
- For axis tilt below 7º accompanied by low rotation use the chart below:
- For low axis tilt with very low revs use the chart below (even with high rotation):
Special notes for axis tilt below 7º: With low tilt, the rotation seems to effect the ratios a lot more than with medium tilts. A high rotation will decrease them a lot (what Mo calls PDW territory) and a low rotation will significantly raise them. There is more of an extreme adjustment comparitively. The ratios increase as the tilt decreases until you reach below 7º to 10º; below that the ratios decrease. Part of the reason is because the maximum drilling angle is 90º and with low tilt, you need ratios which will take the ball down the lane. Here is a PDF chart on how to adjust Athery's chart, especially when low tilt is accompanied by high rotation.
Step #2 - Adjust the Initial Ratio For High Or Low Rotation
Amount of adjustment necessary depends on the relationship between rotation and ball speed.
- High rotation and/or high rotation accentuated with speed dominance = decreased ratios (use boxes further right on the chart)
- Low rotation and/or low rotation accentuated with rev dominance = increased ratios (use boxes further left on the chart)
Step #3 - Find The Ratio Range (for calculating symbiotic layouts)
The maximum ratio and minimum ratio (drill angle and val angle) which should be utilized with your personal sweet sums is defined as your ratio range. This is how far you can deviate your ratio both higher and lower from your benchmark ratio. It can be calculated by choosing boxes left and right of your chosen ratio on the chart above. Mo very seldom gives an extremely large ratio range. It is more common with very low or very high tilt. A +/- of around 0.5 above and 0.5 below benchmark ratio seems to be close to the average ratio range.
You need to determine your personal ratio range to use in conjunction with your total sums to accurately calculate layouts for your personal specs or sweet spot.
- Mo frequently uses the lower ratio range for easier THS wet / dry patterns for more control and mid-lane reaction
- Mo frequently uses the higher ratio range (a defined break shape) for flatter or more demanding patterns to create a stronger reaction to friction.
Please note: On ratios less than 1:1, Mo sometimes expresses ratios with the val angle reduced to :1 example: 1:1.25 would be expressed as .8:1 (.8:1=1:1.25, etc.)
Ratios determine the balls break shape.
- The drill angle helps determine the length of the skid phase of ball motion.
- The val angle helps determine the length of the hook phase of ball motion.
- The drill angle + val angle = the total length of ball motion before the ball reaches the roll phase.
- A higher ratio of the drill angle to the val angle = longer and quicker reaction to the dry. (more of a skid /snap ball motion)
- A lower ratio of the drill angle to the val angle = earlier and slower reaction to the dry (smoother & more continuous ball motion.)
Drilling and Val Angle Math Examples
The following are examples of how to do the math for the ratios. You will divide the total sums of the layout by the sum of the ratio you are looking for. Remember with this simple math, you are always finding the smaller angle (drill angle or VAL angle) of the ratio.
Smaller VAL Angle Example
- 90º total sums with a ratio of 2:1
- 90º divided by 3 = 30º val angle
- 90º - 30º with a 2:1 ratio = 60º drilling angle
- Results in a 60º drilling angle and 30º val angle.
Smaller Drill Angle Example
- 90º total sums with a ratio of 1:2
- 90º divided by 3 = 30º drilling angle
- 90º - 30º with a 1:2 ratio = 60º val angle'
- Results in a 30º drilling angle and 60º val angle.
Control Layout Example
Find a control layout from 90º total sums using a 2:1 ratio (+/- 0.5). For a control layout, you would add the 20º and subtract the 0.5 ratio.
- 90º + 20º = 110º total sums
- 110º divided by 1.5:1 ratio (ratio has been adjusted with -0.5)
- (1.5+1)= 2.5
- 110º divided by 2.5 = 44º (round to 45º val angle)
- 110º - 45º = 65º drilling angle
- 65º drill angle with 45º val angle = a control layout using 90* (+/- 20º) total sums with a 2:1 (+/- 0.5) ratio.
Long & Strong Layout Example
Find a long and strong layout from 90º total sums using a 2:1 ratio (+/- 0.5.). For a long and strong layout, you would add the 20º and add the 0.5 ratio.
- A control layout using 90º (+/- 20º) with a ratio of 2:1 (+/- 0.5)
- 90º + 20º = 110º total sums
- 110º divided by 2.5:1 ratio (ratio has been adjusted with +0.5)
- (2.5+1) = 3.5
- 110º divided by 3.5 = 31º (round to 30º val angle)
- 110* - 30º = 80º drilling angle
- 80º drill angle with 30º = a long & strong layout using a 90º sums (+/- 20º) with a 2:1 (+/- 0.5)ratio.
Mid-lane Layout Example
Find a mid-lane layout from 90º total sums using a 2:1 ratio (+/- 0.5). For a mid-lane layout, you would subtract the 20º and subtract the 0.5 ratio.
- 90º - 20º = 70º total sums
- 70 divided by 1.5:1 ratio (2:1 ratio adjusted with the -0.5)
- 70º divided by 2.5 = 28º (rounded to 30º val angle)
- 70º - 30º = 40º drilling angle
- 40º drill angle and 30º val angle = a mid-lane layout using 90º (+/- 20º) with a ratio of 2:1 (+/- 0.5)
Totally Strong Layout Example
Find a totally strong layout from 90º total sums using a 2:1 ratio (+/- 0.5). For a totally strong layout, you would subtract the 20º and add the 0.5 ratio.
- 90º - 20º = 70º total sums
- 70º divided by 2.5:1 ratio (ratio has been adjusted with +0.5)
- (2.5+1) = 3.5
- 70º divided by 3.5 = 20º
- 70º -20º = 50º drilling angle
- 50º drill angle with a 20* val angle = a totally strong layout using 90º (+/- 20º) with a 2:1 (+/- 0.5) ratio.
Choosing Pin to PAP distances
- For a more aggressive coverstock ball use larger angle sum layouts
- For a less aggressive coverstock ball use smaller angle sum layouts
If the ball design creates a later, sharp break point, use lower ratio (lower drilling angle to VAL).
If the ball design creates a sooner, forward rolling ball, use more ratio (higher drilling angle to VAL)
High tilt players use Pin to PAP distances of 4 1/2" to 5 3/4" (with Asymmetrical balls)
- 4 ½” Pin to PAP distance will make the ball come off the spot hard (more angular)
- 5 ¾” Pin to PAP distance will make the ball roll forward sooner
Asymmetrical Balls exhibit most flare at Pin to PAP distances of 2 3/4" to 6 1/4"
Symmetrical Balls exhibit most flare with Pin to PAP distances of 3 to 4"
Retaining Axis Rotation & Axis Tilt (increase skid, reduce flare):
- To retain Axis Rotation and Axis Tilt in SYMMETRICAL equipment, we would tend towards longer pin-pap (> 4") distances, while ASYMMETRICAL equipment we use shorter pin-pap distances (< 3"). We would also chose higher angle ratios (2:1 - 3:1) to promote a longer first transition to make the most of what Axis Rotation and Axis Tilt is available at release.
Burning Off Axis Rotation & Axis Tilt (decrease skid, increase flare):
- To burn off Axis Rotation and Axis Tilt quicker in SYMMETRICAL equipment, we would tend toward Max flare pin positions (3" - 4"), while longer pin distances (4"+) in ASYMMETRICAL equipment. We would also chose lower angle ratios (1:1 - 1:2) to get the ball to reach the first transition sooner, while trying to eliminate jumpy back end reaction that tends to accompany high Axis Rotation and Axis Tilt.
Roll the ball, then use balance holes to fine tune reaction
- Start with a smaller size hole (3/4") at least 2-1/2” deep
- P1 hole = Reduces drilled dynamics
- P2 hole = Maintains drilled dynamics
- P3 hole = Increases drilled dynamics some
- P4 hole = Increases drilled dynamics more
- (This is a very basic interpretation of the Gradient Line Balance Hole technique. Please visit http://www.morichbowling.com/Drilling/GradientLineBalanceHole/GradientLineBalanceHole.htm for more detailed information.)