Hook Variables: Part 1 | Forces Controlled by the Bowler

Hook Variables: Part 1 | Forces Controlled by the Bowler

So, you want to buy a hook ball. Start saving your money. But not for the most expensive ball on the market, but instead for lessons from a USA Bowling Certified Coach. Because you can’t buy a hook ball, you throw one. Yeah, I know the balls they produce today may be nicknamed hook-in-the-box. But remember this, every ball made will hook or go straight based on how it is released. The good news is there are many variables related to the ball type and drilling pattern that determines the balls hook potential. This is what you are looking for when you purchase that new weapon that will help you overcome the lane condition that has your number.

 

The more you understand about the forces you apply to the ball and the characteristics of the ball, the better prepared you will be when shopping for your next ball. It is complicated and can be intimidating if you do not understand all the variables involved. In the next few articles, I will analyze all the variables controlled by the bowler, the bowling ball, the environment, and ball driller that affect the movement of a bowling ball. We will start naturally with the most important factor of all, you the bowler.

 

As I stated earlier, bowling balls do not hook by themselves, the bowler makes them hook with their release. And the bowler can also make them go straight with their release. Beginning bowlers throw the ball straight for more control and when their skills improve, they learn to throw a hook. An advanced bowler can change the amount of hook by altering their release.

 

There are four forces imparted to the ball by the bowler:

 

  • Axis Rotation
  • Axis Tilt
  • Revolutions
  • Ball Speed

 

Knowing these numbers for yourself and understanding them will help you in determining what type of ball you need and how you drill it. Your coach and ball driller needs this info as well. You may get different opinions as to which bowler variable is most important, but one thing is certain; To make a bowling ball hook, you must have some degree of axis rotation. So, we will discuss that one first.

 

Axis Rotation

If you roll a bowling ball with the thumbhole facing the pins, and the ball rolls end over end, it will roll completely straight because the axis of rotation is parallel to the direction of rotation. The ball rotates around an axis and when this axis is parallel to the direction the ball is traveling, there is zero degrees of axis rotation and it will roll straight down the path it is heading. When you release the ball with your hand on the side, the ball is rotating at a ninety-degree angle to the direction it is traveling. This will make the ball hook in a right to left direction (for righthanders) when enough friction kicks in. The ball is attempting to travel in the direction it is rotated which makes the ball turn to the left. At the same time the axis is attempting to rotate in the direction the ball is traveling. This makes the ball hook out and roll end over end. When this happens is determined by the amount of friction between the ball and the lane, your ball speed and rev rate.

 

Now what does all this mean in simple terms:

 

 Basically, if you have a higher degree of axis rotation your ball will make a greater change of direction – sharper snap. This ball will slide further down the lane before hooking. If you release the ball with your hand more behind the ball, you will have less axis rotation and your ball will not slide as far before hooking. There is no right or wrong way, but there are advantages and disadvantages of each type of axis rotation. A lower degree of axis rotation (30 degrees) is easier to control but does not create as much pocket entry angle. A higher (90 degrees) creates the steepest entry angle but is harder to control and more sensitive to lane conditions. A 45-degree axis of rotation is most versatile.

 

Axis Tilt

Your axis tilt is basically a measurement of your ball track. The smaller your ball track, the more your axis is tilted. A full roller rolls around the compete circumference of the ball and therefore has no axis tilt. A spinner uses a smaller circumference which creates more axis tilt. More axis tilt makes your ball slide further down the lane. Bowlers like this prefer dryer lane conditions. Knowing your axis tilt is important when selecting a ball and determining the ball layout.

 

Revolutions

Your rev rate is like the horsepower in an engine. A higher rev rate means a stronger ball reaction. You can place a piece of white tape above the fingers and actually count the number of revolutions the ball makes going down the lane, but this is not exactly the same as your rev rate. Your rev rate is the number of revolutions per minute (RPM) that your ball is rotating. If two balls have the same rev rate but one is thrown slower, the slower one will have more total revolutions. The rev rate can increase as the ball travels down the lane because of friction and the bowling ball’s core dynamics. The exact figure is not as important as having a general idea if you are a high or low rev player. With regard to revolutions, more is always better. A lower revolution player will not notice differences in bowling balls and layouts as much as a high rev player because revolutions magnify all the other variables.

 

Ball Speed

The last variable controlled by the bowler is ball speed. This is the easiest to understand and the easiest to change. I would like to point out that, although it is easy to change your ball speed, it is difficult to master the skill of altering ball speed at will, with accuracy and consistency. The late, great Earl Anthony was probably the best ever at controlling his ball speed. Matching the proper ball speed for the lane condition is one of the keys to maximum carry potential. The problem is most bowlers have a natural speed that suits their arm swing and footwork tempo and changing this speed is difficult to do consistently. Today’s highly reactive bowling balls will overreact with varying speeds. If you can change your ball speed and maintain your accuracy it will expand your range of lane conditions and increase carry under some conditions. The whole secret to carry lies in matching the friction between the ball and lane surface so your ball begins to slow down at the proper point to give you the maximum hitting power. If you can do that your carry percentage will top 90%. The challenging part is that friction varies from day to day, lane to lane and every shot as the oil moves around. And that is what makes bowling challenging and keeps you coming back. Because if it were easy, you would get bored.

 

If you do not know your release variables, have yourself measured by a USA Bowling Certified Coach, or do a self-analysis. But be honest with yourself for the best results. In the next article in this series, we will look at all the variables of a bowling ball.

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