*BELOW is an excerpt from USGolfTV’s latest e-book called “The Science of the Slice.” The e-book can be download and read in full, Science-of-The-Slice-Ebook-10


One of the final key aspects in understanding the “Science of the Slice” is understanding the moment of truth. The point of no return. Impact.

Have you ever hit that shot that you barely felt? That one with the sharp, piercing sound and the soaring ball flight. The one that when you look at the club face, you see a few faint marks of a dimple right on the center of the clubface. The one that made the fellas in your group pause and stare, keeping them away from their typical ridicule.

Sure, the spin, the face, the path, and the angle of attack all played a role in that strike, but without the ball being hit square in the center of the club face, the result would be somewhat, a moot point.

Hitting the ball in the center of the face is the key to any great golf shot.

Modern day radar machines tell us that the ball is connected with the face for roughly 1/2000 of a second during impact with the driver. This means, during an entire round of golf, we don’t even hit the ball for 1 second.

Impact happens that fast.

But the effect impact has on the ball’s flight is insurmountable.

After learning every element of this E-book in-depth, here’s a story from a PGA teaching professional to show how important hitting the center of the face is.

“Last summer, one of our students was working with us on our practice range. We were using our launch monitor and taking tabs of the numbers he was producing after each shot.

The numbers showed that his face was a bit open, only a few degrees. At the same time, his path was coming back across the golf ball, a few degrees back to the left. He was a right-handed golfer, so do you think he was hitting big slices with his driver?

If you thought that, you’d actually be wrong.  He was hitting duck hooks!

After further examination, we learned a fatal fault to his striking of the golf ball.  He was hitting his driver consistently off the toe. Therefore, we needed to fix his contact before anything else mattered. We started working drills to hit the center of the club face more often.”

It’s amazing how impact influences the ball so much.

If this student were to take lessons from someone who only saw the launch monitor numbers, they would suggest he starts moving the path more to the right of his target line.

But this would only make matters worse!

He needed to get impact with the ball figured out before any of that played a factor at all.

All of the laws we’re talking about where the path and the face all work together to create ball flight, are all only true if the student is hitting the ball on the center of the club face.

Impact represents the moment of truth.

Now you might be asking yourself—how is this true? How does hitting the ball off the toe matter at all?

Well, the answer lies in a term called “gear effect.”

What is Gear Effect?

Gear effect is the term used to describe the behavior of the club through impact. It’s not a simple concept to explain without a Phd in physics, but we’ll explain our understandings as it relates to the golf club.

Here’s a great video with Andrew Rice explaining it:

Let’s go back to the student in the above example.

Since he was hitting the ball severely off the toe, the impact was causing the face to shift during impact. As it shifted, imagine the heel of the club opening more, as the weight of the golf ball impacted the toe of the driver.

This behavior caused the ball’s axis to tilt in toward the face, causing the axis to change. This produced that ball’s hook spin, as opposed to a fade. This is gear effect in action.

Gear effect doesn’t only play a role during toe strikes though. Gear effect plays a role in all shots that miss the center of the club face.

Let’s go through a few more examples.

Examples of Gear Effect

Hitting the ball high on the face (toward the crown of the driver), will change both the launch angle and the spin rates. The launch angle will be high, and the spin will be low. We know this through understanding the physics, while also testing it out on launch monitors.

As far as launch conditions go for a mishit, hitting the ball high on the face may be the healthiest of the mishits, assuming you don’t leave the top of your driver with a dreaded scuff mark!

Hitting the ball on the heel will cause the ball to launch as though it was pulled, but the ball will move back toward the target line in the form of a slice. The heel will take some of the spin off, hopefully reducing the potential slice.

Hitting the ball low on the face brings the spin up and the launch down, not optimal for driving the golf ball. This will greatly reduce distance. And added spin will accentuate any slice a golfer may already have on his golf ball.

All of these numbers are impacted by gear effect.

Gear effect is also at its greatest effect on larger headed clubs (i.e. your driver). In testing, PGA professionals including our own at USGolfTV, have found that clubs with a bigger head are more affected by gear effect. This is caused by their center of gravity in relation to other clubs.

So know this: gear effect will have the greatest impact on your ball flight with your largest club head in the bag.

So to make sure you’re hitting the center of the face. There are a number of ways you can do this, including impact tape, or a can of Dr. Scholls foot spray sprayed on the clubface. Send that smash factor through the roof with perfect center strikes!