Alpha Golf

Coefficient of Restitution (COR) is a physics term for the value representing the ratio of velocities before and after an impact. An object with a COR of 1 collides elastically, bouncing perfectly with no energy loss. While an object with a COR of 0 is said to collide inelastically, effectively “sticking” to the object it collides with. Mathematically, COR is the square root of the ratio of the height of one bounce to that of the preceding bounce.

Golfers paid more attention to COR after the USGA started measuring and regulating clubs for COR in 1984. The thinking was that a clubface with a “trampoline” or “spring-like” effect would send balls flying 400+ yards off the tee. So they limited COR to 0.83. (BTW, this rule coincidentally came into play when manufacturers discovered that titanium drivers were much more ideal than steel drivers in creating enormous ball speeds)

Maximizing COR

There are 2 keys to maximizing the COR of a driver:

1) High grade titanium face - SP700 and 15-3-3 titanium are the best choices for elastic collisions

2) Super Thin face - a thin face provides a “spring-like effect” where the face momentarily depresses at initial contact and then “springs” back into shape at launch.

If the face is too thin, the driver can crack at high swing speeds. If the face is too thick, you lose the spring-like effect where the face won’t depress. The right tradeoff of thickness for the particular type of titanium being used is what keeps us golf designers busy in the labs!

But the R&D is worth it - all golf drivers made by Alpha hit the maximum COR!

Moment of Inertia (MOI) has been a popular buzzword in golf recently. Let’s apply MOI to the design of golf drivers in this discussion.
MOI is the inertia or resistance of a rigid rotating body with respect to its rotation. In other words, it’s the measure of difficulty in changing the angular motion about the axis of rotation. High MOI means more resistance to club twisting, so we want to maximize this resistance as much as possible.

During a driver swing, the clubhead will twist if it doesn’t hit the ball on the axis of the center of gravity. The less a club twists before impact, the more stable it is. And, therefore, the straighter and farther the ball goes. So a high MOI promotes forgiveness in off-center strikes.

The USGA imposes a limit in MOI in drivers of 5900 (g*cm^2). In a letter to manufacturers last year, the USGA said “further increases in MOI could reduce the challenge of the game by reducing the skill required to hit the ball straight. In addition, that could also result in an increase in average driving distance by reducing the likelihood that swinging faster will produce a poor result.”

So there you have it - MOI is so important that making it too high will give some golfers an unfair competitive advantage in distance and accuracy. But that doesn’t stop golf club designers like Alpha from getting as close to the USGA MOI limit as possible (without exceeding 5900).

So how do we maximize MOI? Without giving too many design secrets away, clubheads with maximum MOI have the following characteristics:

1) 460CC - the larger clubhead naturally puts the center of gravity deep inside the head, away from the face. The separation of mass and COG raises the MOI metric

2) Perimeter weighting - More weight can be pushed out farther from the center of gravity of the clubhead and towards the outer shell. Square drivers are an example of this. But drivers with traditional geometries can also push weight out.

3) Large club face with variable weighting - more distance and weighting on the heel and toe again separates mass from the COG axis of rotation, reducing torque and twisting.
Many modern golf drivers are designed with MOI being the most important parameter to optimize for.

The “hybrid golf club” gets its name from combining the feel and accuracy of irons with the power and distance of fairway woods. Hybrid golf club sets are exploding in popularity among recreational golfers since they’re a lot easier to hit than long irons. Yet, more than 50% of pros also have a hybrid in their bag as reported by the Darrell Survey.

How are they designed?

Hybrid heads are made from hollow steel (although the titanium hybrid is starting to make its way into golfers’ bags). The center of gravity is positioned towards the back and near the bottom of the club head. The lower COG increases the launch angle, making the effective loft higher than that of a similar iron.

The shafts are usually steel. And their length and lie (shaft angle) are closer to an iron. The stiffer and shorter shafts make them easier to hit than fairway woods.

How does a hybrid perform?

Since the head and face of a hybrid golf club is modeled after a wood, you’ll get the same sort of impact as a wood - namely a huge impact with high coefficient of restitution (COR). Combine this “tramopline effect” with a high launch angle, and the hybrid gives you a lot of backspin.

So you’ll get an airborne shot with a high spin rate. This is a recipe for a ball that drops sharply with little roll.

How do I swing a hybrid?

The swing mechanics are like those you’d use for mid-to-long irons. So play the ball slightly forward in your stance, and use your normal grip, stance and posture. Make a sweeping-type swing, hitting down and through the ball.

If you decide to tee off with a hybrid, tee it up a little higher than you would with an iron. And as always, let the club do the work!

When do I use a hybrid?

I think there are 3 situations when a hybrid is the ideal “rescue club“:

1) The dreaded long iron shot - when you need distance, but need the accuracy to get on the green. Most amateurs are inconsistent with long irons. This is what the hybrid was designed for.

2) In the rough - remember your swing is just like an iron. But because of the added weight of the head, you’ll have a slower clubhead speed. This means you can cut through tall grass with more momentum at contact than an iron. And you sure as hell don’t want to swing a fairway wood when you’re in the rough.

3) A hazard in front of a green - you want enough carry in the ball but little roll upon landing. A fairway wood or long iron will get you the distance to get over the hazard, but will roll away. Your hybrid, on the other hand, will stick where it lands.

Happy (hybrid) golfing!

The proper golf swing (not to be confused with the perfect golf swing) can be achieved by any golfer. There are some underground training tricks that well-known golf pros use to teach their beginner students.

1) Put a tee in front of the ball

Place a tee 5-6 inches in front of the golf ball when hitting your golf driver. When you swing, hit not just the ball but the tee as well. This focuses you on swinging through the ball, and not at it. Your follow-through after impact will also be improved with this technique.

2) Close your eyes on a practice swing

Take a full practice swing with your eyes closed. This heightens your awareness of posture and balance. Try to determine if your club head is opened or closed while you swing with your eyes closed. You’ll be a lot more sensitive to keeping balance throughout the swing after a few blind practice shots! Many beginners can’t help but have their clubface open, in which case an offset golf driver might be the best solution.

3) Use your club to correct your posture at set-up

Hold your club shaft against your lower back. Bend over while keeping your lower back straight and parallel against the club. Maintain this posture, then drop your arms to let them hang naturally before gripping the club.

4) Use 2 parallel clubs to set your alignment

Put your best new driver along your intended target line. Put another titanium golf driver down along your feet. Both clubs should now be parallel to one another, forcing you to have your shoulders parallel to the target line. Parallel shoulders means parallel arm movement during the swing.

5) Put a penny on your shoe

Put a penny towards the front of your left shoe. Try to keep the coin on your shoe during your swing. If the penny falls to the right of your shoe, you’re putting too much weight on the back foot during the backswing. If it falls to the left of your shoe, you’re shifting too much weight during the finish.

6) On a scale of 1-5, grip a 2

Too many beginner golfers grip the club too tightly. Grip your club on a scale of 1 to 5, one being the weakest and five being the strongest. Go through each number slightly gripping harder as you near five. Then go back to 2. This grip level should let you swing the club freely while still maintaining control.

7) Watch your swing in the mirror

In front of a mirror, first check out your grip - a “V” between the thumb and forefinger should point at your right shoulder. Then check your posture, alignment, and stance. Finally, see if you look balanced while taking a swing.