Guide #11 - Last updated May 2021

How to Read an Oil Pattern Sheet

Kegel, a company in Lake Wales, Florida, is the world's leading provider of lane oiling machines (sometimes called lane conditioning machines). As a result, the program sheet format used by Kegel has become the de-facto standard used to communicate pattern specifications to bowlers. Therefore, we use that format for our explanation. Below is an example of a Kegel oil pattern sheet. Zoom in on the image to see the detail, or click here to see it enlarged in a separate window.

The four parts of the sheet are:

Heading - The 3 or 4 rows of numbers at the top of the sheet, which are the key parameters of the pattern.

Machine Settings - The two boxes of numbers on the left of the sheet, containing the coordinates used to program the lane oiling machine.

Overhead Chart - The image on the right of the sheet showing an overhead view of the pattern as it would look if the oil had color instead of being invisible.

Composite Graph - The image at the bottom of the sheet, showing a view toward the pins as if all of the oil of the pattern had been colored, brought forward from the lane and piled up at the foul line. The two boxes of numbers above the graph show ratios calculated from that graph.

If you are just starting out (or are in a hurry), the three key pieces of information to grab from an oil pattern sheet are:

1. Oil Pattern Distance (found in the Heading).

This is the distance down the lane that the oil has been applied from the foul line to the pins. Tournament oil patterns range from 32 feet to 52 feet. In this case, the length is 41 feet, which is roughly 2/3 of the way towards the pins. House patterns, which are the oil patterns that bowling centers use for most of their leagues, are usually around this length. The distance from the foul line to the pins is 60 feet. So, on a 52 foot pattern, your ball has only 8 feet to turn toward the pins. Compare that to a 32 foot pattern, with 28 feet to the pins and lots of chance for the ball to overhook.

Kegel's widely-used Rule of 31 says that, by taking the oil pattern length and subtracting 31, you will get the point at which your ball should leave the oil to have the best angle toward the pocket. For this pattern, 41 less 31 leaves 10, meaning your ball should leave the oil on the 10 board. It's important to note that this is only a starting approximation to use in determining the best location based on your game.

2. Volume Oil Total (found in the Heading).

This is the total oil applied to each lane. Tournament oil patterns range from 20 to 30 milliliters. Generally, the higher the oil volume, the more aggressive the bowling ball you will need, and vice-versa. In this case, the volume of oil is 25.32 milliliters and is very consistent with what house patterns use.

3. Pattern ratio (from the Composite Graph section).

The lower right ratio, which is 4.5 to 1 in this case, represents the ratio from the area between the center of the lane and the first arrow on the right (at the 5 board).  The lower left ratio is that same ratio for the left side of the lane, which is the same in this and most patterns, but different in a few others. By comparison, most house patterns have ratios of 8 to 1 or more, meaning the oil is concentrated in the center of the lane. The outer edge of that oil concentration helps guide your bowling ball to the pocket. The lower the ratio, however, the more evenly the oil is applied across the lane, the less help you will have, and the more getting to the pocket will depend on just how good a bowler you really are (as explained in Oil Pattern Basics).

USBC defines sport patterns, the most challenging patterns, as those with ratios of 4 to 1 all the way down to 1 to 1, which is perfectly flat. It defines challenge patterns as those with ratios above 4 to 1 up to 8 to 1. In this case, 4.5 to 1 means this is a challenge pattern.

Once you are comfortable with with three key items above, here are a few other key bits of helpful information to get from the oil pattern sheet:

4. Shape of the pattern (from the Overhead Chart).

The darker the color on the Overhead Chart, the higher concentration of oil in that particular part of the lane. House patterns usually have oil concentrated in the center of the lane between the 10 board on the right and the 10 board on the left. In this case, however, the pattern has a noticeable amount of oil outside the 10 boards. This is a clue that you will need a more aggressive bowling ball in order to get through the oil. The further down the "heads" (the first 20 ft of the lane) that outside oil is present, the more aggressive the ball you will need.

The part of the lane after the heads running up to the end of the pattern is called the "midlane" and the portion after the end of the pattern is referred to as the "backend."

5. Conditioner used (from the Heading).

Manufacturers call their oil products "conditioner" to reflect the fact that each one is more than just oil - it is oil plus a set of additives that give the oil a unique set of characteristics. For example, Kegel's Ice oil tends to allow your ball to hook more, but the balls thrown will be more likely to take oil they pick up in the earlier part of the pattern and track it down to the previously dry backend (the oil tracks are called "carry down'). In comparison, Kegel's Fire oil breaks down more quickly than Ice and yet is more predictable. Knowing how these patterns evolve during play can help you decide which adjustments to make.

In this case the pattern sheet does not specify a conditioner, so the bowling center is likely to use whatever they normally use for their house patterns. Even if the pattern sheet *does* specify a conditioner, you will find that only the national and higher-level tournaments will actually use it, while the rest will use the tournament center's usual house pattern conditioner.

6. Forward Oil Total and Reverse Oil Total (from the Heading).

Generally, forward oil creates the "shape" of the pattern, while reverse oil gives you "hold area." The oiling machine buffs forward oil beyond the forward-oiled area to define the "end zone" of the oil pattern, at the leading edge of the dry backend. The buffed area serves as smoother, blended transition zone that allows more room for error.

In this case the forward volume is 15.64 and reverse volume is 9.68, a common balance.

7. Are two different oils being used? (from the Heading).

Some of the newer oiling machines have two tanks, so the newer oil pattern sheets will specify a Tank A Conditioner and and Tank B Conditioner. Most of the time they will be the same. Difficult oil patterns will use Tank A for forward oil and Tank B for reverse oil. Very difficult patterns may use each oil in one or both directions. We'll show you how to figure this out in our Advanced Understanding of an Oil Pattern Sheet guide. But note: If two conditioners are specified but the pattern is being used for a tournament that is not a national or other high-level tournament, chances are good that the tournament center's usual house pattern conditioner will be in both tanks.

Next: Why You Can't Count on an Oil Pattern Always Playing The Same Way

Previous: Oil Pattern Basics