We are searching data for your request:
Upon completion, a link will appear to access the found materials.
The curve of a driver's face helps correct off-center hits.
At first glance you might assume that all your golf clubs have flat faces, because hitting a round ball with a curved object sounds like a more difficult task. But if you take a close look at your driver, you'll see that its face is slightly curved, both horizontally and vertically. This curvature actually helps you hit your drives straighter, and with better trajectories, than if your driver had a flat clubface.
The gear effect causes your clubhead to rotate around its center of gravity when you hit the ball off-center. If you hit the precise sweet spot with your driver every time, the impact would align perfectly with the center of gravity and your clubhead would not rotate. In that case, you could use a driver with a flat face. But nobody hits the sweet spot every time. For example, imagine hitting the ball closer to the club's toe. The toe end of the club is pushed backward a bit by the impact -- relative to the heel -- which causes the clubhead to rotate toward its center of mass. As a result, the ball slides toward the center of the face and receives some sidespin before flying off of the club. The larger the clubhead, the greater the gear effect. That's why drivers and other woods have curved faces, and iron faces are flat.
A clubhead's horizontal curvature is known as its bulge, which is designed to partially counter the gear effect. If you hit the ball closer to a driver's toe, the face imparts sidespin that causes the ball to hook -- curving to your left, if you're right-handed. But the clubface's bulge creates an angle that pushes the ball to your right at impact. The ball will still curve toward your left, but instead of starting on target and then curving left, it starts off-target to the right and then curves back toward the target. The same principle applies to heel hits, except that the bulge pulls the ball toward the left, then the sidespin caused by the gear effect curves the ball to the right.
Vertical Gear Effect
The gear effect also applies along the vertical axis. If you hit the ball too low it slides upward toward the center of the clubface and then pops high in the air after impact, which costs you distance. The driver's vertical curvature -- known as its roll -- has the effect of de-lofting the clubhead, producing a lower trajectory than you'd have with a flat face, which results in more distance. A ball hit too high on the face receives downspin, causing the ball to curve downward excessively. The driver's roll gives those shots higher launch angles and, again, greater distance.
Importance of Alignment
The driver's curvature can make alignment more difficult when you're on the tee. Make sure to square the center of the clubface with the ball. If you align the clubface off-center, you'll produce excessive sidespin that the bulge can't overcome. If you have trouble with your alignment, look for a driver with an alignment guide on top of the clubhead.
Measuring Bulge and Roll
Club fitters measure a driver's bulge and roll using a handheld object with four curved sides, called a face radius gauge. Each side corresponds to a different radius, measured in inches -- typically 8, 10, 12 and 14 inches. The club fitter holds one side of the gauge horizontally against the driver's face. If the gauge is flush against the face, then the bulge radius is correct. Holding the gauge vertically against the clubface measures the driver's face roll.