Ratio of Angles
? The “Ratio of Angles”
The ratio between the drilling angle and the VAL angle gives insight into how sharp or smooth the ball’s motion will be.
Ratio = Drilling Angle : VAL Angle
? Higher Ratio (e.g., 70° : 30°)
-
More length in the front part of the lane
-
Sharper backend reaction
-
Best for high-rev players or when lanes are dry
? Lower Ratio (e.g., 40° : 70°)
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Earlier, smoother roll
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More control on heavier oil or sport conditions
-
Best for speed-dominant or lower-rev players
? Example Layouts
| Bowler Type | Example Layout | Ratio | Reaction Shape |
|---|---|---|---|
| Speed-Dominant | 40° × 4" × 70° | 1:1.75 | Earlier, smoother reaction |
| Balanced (Tweener) | 55° × 4½" × 40° | 1.4:1 | Benchmark shape |
| Rev-Dominant | 70° × 5" × 30° | 2.3:1 | Length with sharp backend |
? Summary
| Term | Controls | Lower Value | Higher Value |
|---|---|---|---|
| Drilling Angle | Skid phase | Earlier roll | Later roll |
| VAL Angle | Backend motion | Sharper | Smoother |
| Ratio of Angles | Overall shape | Smooth/control | Angular/strong |
? In Short:
The ratio of angles defines how fast or slow your ball transitions from skid → hook → roll.
