Characteristics of a Wood Club Face: Loft, Face Angle, Bulge and Roll
Loft is the vertical angle formed between the club face and the hosel (where shaft and club head are connected). A driver has usually the lowest loft of all woods, ranging somewhere from 7 to 13 degrees. The loft causes the ball to spin: once the ball touches the club face it will start to quickly roll up the face, causing it to rotate around its horizontal axis. This spin is good as it will make the ball fly further and make it less susceptible to wind blowing from the side. The higher the loft of the club the greater the spin and the higher the trajectory of the ball flight, but the ball will not roll very far. In contrast, a ball hit with a lower lofted club will not fly very high by roll a lot more. Generally a beginner golfer is best served by a higher lofted club.
Face Angle refers to the horizontal angle of the club face versus the target line: if the club face is exactly perpendicular to the target line the face angle is considered ‘neutral’. This is the case for most drivers/woods and considered the default. The effect is that, upon square impact, the golf ball will fly along the intended target line.
However, some golfers, especially those who have a tendency to regularly slice the ball, have difficulties to deliver the club face in an absolutely square (perpendicular) position. Upon impact their clubface tends to be a bit open, which in turn causes the golf ball to slide or roll across the club face towards the toe of the club, thereby putting some side spin on the ball. This side spin makes the ball go off the target line. The more open your club face is the more spin the ball gets, and the worse your slice will be.
In order to compensate for this open club face problem you can either work on your swing or buy a wood with a closed club face angle: when you put the club down at address the club face actually points towards the left (for RH golfers). When struck ‘normally’ this would cause a hook, but for a slicer it may actually correct the open club face problem and result in a straight shot down the target line.
Bulge and Roll: if you look closely at the clubface of any wood you will see that the face is not totally flat but slightly curved both horizontally and vertically. This is needed to give the face proper stability, and not to cave in upon impact with a golf ball. The horizontal curvature is called ‘bulge’, and the vertical (you probably guessed that…) is called ‘roll’.
Bulge is no problem as long as you hit the ball with the center of the club face. However, if you hit it at the toe of the club you would have basically an open club face as mentioned above. This is even more exaggerated because the clubhead rotates around its vertical center-of-gravity axis whenever the ball is hit off the toe (or heel for that matter). The effect would again be to impart side spin on the ball, resulting in a slice. On the other hand, if you hit the ball on the heel of the club your shot would go left (for RH golfers) but will curve back towards the target line. If you experience inconsistency with your shots going left and right you may benefit from a driver/wood with a larger (flat and non-curved) sweet spot, i.e. the currently popular square drivers.
In short, bulge is your enemy. Case in point: I once hit the ball with the extreme toe corner of my driver, resulting in the ball shooting off in a 90 degree angle to the intended target line. It hit my wife who waited in the golf car at a presumably safe spot – fortunately she wasn’t injured seriously (‘only’ a ball sized mark on her upper thigh that changed color from red to blue to green over the following weeks), but it cost me a couple of dinners and 2 pair of shoes to be released from sleeping on the sofa.
Roll, as mentioned, refers to the vertical curvature of the club face. The club face has already an angle (i.e. some 9 – 12 degrees of loft for a driver) which helps to impart some desired spin onto the ball, thus helping it to get higher and farther than it would fly without spin. However, following in essence the same principles as above you can imagine that a ball that is struck too high on the club face will have a high trajectory but a short distance, while a ball struck too low will become a ‘worm burner’.
Nice post. I was thinking about your post today while I played nine. Of course, the ground was frozen, but I was driving the heck out of the ball off the tee. In my mind were abstracted thoughts about the shape of the face of my driver - bulging and lofted and angled and all. The effect was to bring concentration down on the ball at impact.
And, holding your post in mind, the intellectual framework, it reminds me of a quote from my favorite golf book, (John Jacobs) " The only purpose of the golf swing is to move the club square to the target at maximum speed. How this is done is of no significance at all, so long as the method employed enables it to be done repetitively. "
And, " Understand the geometry of impact- clubface angle, swing path, angle of attack, and clubhead speed- and you'll be able to read your own ball flight, analyze your own mistakes, and correct your own faults. "
And, " Learning what I call the geometry of the game is a mental, not a practice-ground process. It isn't difficult but it involves sitting down and thinking for a few moments."
(About angle, bulge and roll and such.)
And, " The distance your ball flies is governed not - as so many golfers think - by your clubhead speed alone, but by clubhead speed squarely applied. Thus long-hitting is as much a matter of achieving the correct 'impact geometry' as using your muscles in a particular way. "
I have a set of Ping EYE 2 Woods. The gear effect is more prononced in these wooden woods than any of the metal drivers I own. This is especially true with the Ping 12* Eye 2 (2 wood). This 2 wood is still (imho) one of the best clubs a new golfer could learn to swing, while developing their swing. FHs
I appreciate the info. Until I purchased this last driver from Diamond Tour golf, I had never seen anyone mention these type of secs. Your blog has been very informative. Thanks. Elfisgregory
What are Face Angle, Bulge and Roll?
