Golf Club and Clubmaking/Clubfitting terms (part 1)

From a guy known as Mack:

Terms and definitions:

1. COG: Center of Gravity. This refers to the spot on the club that has the most concentrated mass behind the face of the club. This is the “balance” point of the whole club head, it is where the mass is centered and where the best contact would occur if the ball were to be hit in this spot.

2. Low COG: Low center of Gravity. The lower the “mass” is located on the club head, the easier it will be to hit the ball higher. A low center of gravity promotes higher ball spin since the ball is stuck “low” then move up the club face adding more spin. When the ball is struck, it will spin backwards in rotation. It takes a split second of time for the ball to begin to rotate. The higher the club face, the higher the spin if the ball is struck low on the club face. As the club move forward after initial contact, the ball will move up the club face (again, a split second of time) and this determines partial launch angle per the loft degree of the club. I say partial launch angle since the shaft has something to do with launch angle as well, but for now we will assume that the shaft is “rebar” and does not flex. The higher the loft (club face angle compared to a vertical plane) the higher the launch. Notice that most higher lofted club heads has larger club faces; this facilities more spin and a higher ball flight.

3. High GOC: High center of gravity. This means that the central “mass” is located higher in the club head. Balls struck lower on the club face will have less spin and will no travel up the club face as stated above. Ball flight will be lower since there is less spin of the ball at initial contact. The major difference between LCOG and HCOG is spin rate and launch angle. Spin creates loft thus higher ball flight.

4. Blade or muscle back. Irons that have no cavity are considered “blades”. Blade irons have small faces with a low COG, mass is placed directly behind the center of the face. Blades tend to be small in nature from heel to toe. Since the head size is small when compared to “modern” irons; shots hit off center create more spin since there is little “face” for the ball to run up on. Since it’s easier to “spin” the ball using blades, blades are the iron of choice for very low handicap golfers and golf professionals for “shaping shots” (side spin). You hear the term “not very forgiving”, well that is true since it requires a precise stroke to hit a blade type iron well. A slight miss hit will send the ball spinning either left or right. Distance suffers on miss hits with blade type irons since the mass is located in the center of the club, not on the perimeter. Mass equals distance.

5. Many wedges are designed as a ”blade” style even today. The higher the loft of the club, the more spin the club creates. So we know that wedges tend to hit the ball high. Wedges impact “Backspin”, this is what makes the ball climb in the air, backspin. When backspin is “high”, it’s very difficult to impart “side spin”. Think of a bicycle tire, when the tire spins it is held in place by inertia, this is the force that keeps the tire upright. The faster the tire spins, the more inertia is exerts thus the tire rolls straight and true. The same can be said with a golf ball. The higher the back spin, the higher the inertia so the ball goes straight and not to the side. It is very difficult to “shape” a wedge shot due to the high amount of backspin. Notice that wedges have a “tall” face when compared to a five iron, the taller face helps to increase backspin. Wedges also have low COG’s to help get the ball in the air.

6. Cavity back irons. Up until the release of the Ping Eye iron, almost all irons were blade style in various forms. Karsten Solheim designed an iron head where the mass was removed from the back of the club face and distributed on the parameter of the club head. Redistributing the mass to the periphery of the club added material to the heel and toe area of the club and helped to reduce distance loss on miss hits. The additional mass also reduced side spin on miss hits keeping the ball on the intended line. Since side spin was reduced, shot shaping became more difficult as ball ended up going in a straight line unlike the blade style head. Cavity back irons have long heel to toe measurements to create an even more forgiving club face. The biggest contribution of the cavity back iron is forgiveness on miss hits out of the toe or in on the heel region of the club face. Cavity back irons help to keep the ball on the intended flight line and reduce side spin. The longer the distance from heel to toe, the more forgiving the iron plays.

7. Leading edge. All irons have a leading “edge”. The leading edge is where the club face meets the sole of the iron. The leading edge is what cuts through the turf or dirt when the ball is impacted. Irons heads are designed to hit golf balls with a descending blow; at impact the ball moves up the club face and is then releases. Without a leading edge; the ball would be hit just off the surface of the turf with little spin.

__________________
True Length Technology Fitter - www.truelengthtechnology.com
It's live! - www.ShipShapeClubs.com
PCS Class 'A' Clubfitter

A new highlight: Golfing the home course on Christmas Day.

I say it too often: If it's golf club shaped, you can play with it.

For the record, I'm a club doctor, not a swing doctor.

hi lowpost
wonderful post and explane's the golf club better than any book i have read.
just one point, in part 6 he said that the ping eye was the first real cavity back iron but it was the ping K1 and the was 12 years before the ping eye, you had the K1, then the k2 and lastly the k3 with an added bar over the top to have the iron have a lower flight as it gave it a higher COG as described in part 3.
cheers
bill

Thanks Bill. In the original post, he credits Solheim Karsten as the man behind Ping, too. LOL.

But I liked his 'plainspeak' style.

hi lowpost
he does explain the parts of a golf club well and you can easily understand why with different combinations of types of club heads and shafts, how you can change the shape of your shots. ie form high to low shots and from forgiving type heads to the very unforgiving blade type that most pros use.
he also puts some light on the very complected way the top shaft makers have made so hard to compare there shafts to others as there are no real standards between different makers and it must be so hard to to compare different type shafts against each other, people like yourself i would think would use only use a small percentage of the many shafts coming out each year as there is no way the small clubmaker can use and test the huge amount of shafts now on the market.
do most club makers stick to a few dozen shafts that they know or is it down to research in finding what new each year.
cheers
bill

__________________
ping zing2 metal driver
ping zing2 metal 3 wood
ping eye2 1 iron
ping zing2 3/9 irons
ping ist 47% wedge
ping zing2 52% s/wedge
ping mb 56% wedge
ping c10 G2I broom handled putter
top flight "T" golf balls
white ping bag

It's some of each, Bill. Some guys like myself only carry a few products, but know them well. Others carry a wide majority of things to try and cater to everybody - but when it comes down to fitting for a shaft, they, like me, stick to a few basic combos that they know well. In other words, if you're set on shaft ABC, most guys will sell you ABC - myself included. But if you're coming for a custom fitting, we'll fit and use product that you'll end up playing.

hi lowpost
there seems to be such a choice of shafts available now for the club golfer, just a few years ago you could only have access to if you were a pro and signed to a manufacture.
now there seems to be so much choice its so hard to know whats what and you really need to go to a fitter to get the heads and shafts matched now.
it seems such a long time since ping started the color coded system in 1972 and set a standard for loft and lie in 1973.
but it seems in the last few years more and more people are seeing that fitting is the way ahead and the only way to get a set of clubs that matched you and not you matching the set of clubs.
cheers
bill

__________________
ping zing2 metal driver
ping zing2 metal 3 wood
ping eye2 1 iron
ping zing2 3/9 irons
ping ist 47% wedge
ping zing2 52% s/wedge
ping mb 56% wedge
ping c10 G2I broom handled putter
top flight "T" golf balls
white ping bag