# Here is a study of club-face rotation...what do you think?

Joined: July 12th, 2001, 12:35 am

AJ Bonar....studies

Studies over the last few years in USA by USPGA Professional, A.J.Bonar, clearly and irrefutably show that the clubface of all top players actually closes at the rate of 2.5 degrees every inch. Simply put, this means that the clubface rotates a full 30 degrees from 6 inches before impact to 6 inches after impact! I quote from a recent e-mail from AJ;

The first measurement I made about the amount of toe rotation was about 17 years ago, and it was done when I had a company, Digital Precision Golf, measure my own clubface to find the difference in speed between the heel and the toe. The chap that owned the company thought my interest was misplaced. He thought it would not be more than 1 mph, at best. On the day following his capture of my 5 iron shot, he called me and said the toe of my 5 iron was traveling 16.5 mph faster than the heel. This seemed to me to be more in line with what I saw on the lesson tee, when students move from the "square face" impact concept to using the dynamic, rotating clubface through impact.

In 1998, I had access to an electro-magnetic technology that measured the clubface in the impact zone. It measured the face rotation, angle of attack, ball/face contact point, and speed. When we tested tour players, we noticed that the rotational function repeatedly gave us 2.5° of rotation per inch of linear movement of the heel.

Joined: January 1st, 1970, 12:00 am
That is NOT a study (n/t)

Joined: January 1st, 1970, 12:00 am
AJ Bonar....studies

Studies over the last few years in USA by USPGA Professional, A.J.Bonar, clearly and irrefutably show that the clubface of all top players actually closes at the rate of 2.5 degrees every inch. Simply put, this means that the clubface rotates a full 30 degrees from 6 inches before impact to 6 inches after impact! I quote from a recent e-mail from AJ;

The first measurement I made about the amount of toe rotation was about 17 years ago, and it was done when I had a company, Digital Precision Golf, measure my own clubface to find the difference in speed between the heel and the toe. The chap that owned the company thought my interest was misplaced. He thought it would not be more than 1 mph, at best. On the day following his capture of my 5 iron shot, he called me and said the toe of my 5 iron was traveling 16.5 mph faster than the heel. This seemed to me to be more in line with what I saw on the lesson tee, when students move from the "square face" impact concept to using the dynamic, rotating clubface through impact.

In 1998, I had access to an electro-magnetic technology that measured the clubface in the impact zone. It measured the face rotation, angle of attack, ball/face contact point, and speed. When we tested tour players, we noticed that the rotational function repeatedly gave us 2.5° of rotation per inch of linear movement of the heel.

This is a study.

Peter
Last edited by sagf_moderator on January 23rd, 2009, 7:44 pm, edited 1 time in total.

Joined: July 27th, 2000, 3:15 pm
AJ Bonar....studies

Studies over the last few years in USA by USPGA Professional, A.J.Bonar, clearly and irrefutably show that the clubface of all top players actually closes at the rate of 2.5 degrees every inch. Simply put, this means that the clubface rotates a full 30 degrees from 6 inches before impact to 6 inches after impact! I quote from a recent e-mail from AJ;

The first measurement I made about the amount of toe rotation was about 17 years ago, and it was done when I had a company, Digital Precision Golf, measure my own clubface to find the difference in speed between the heel and the toe. The chap that owned the company thought my interest was misplaced. He thought it would not be more than 1 mph, at best. On the day following his capture of my 5 iron shot, he called me and said the toe of my 5 iron was traveling 16.5 mph faster than the heel. This seemed to me to be more in line with what I saw on the lesson tee, when students move from the "square face" impact concept to using the dynamic, rotating clubface through impact.

In 1998, I had access to an electro-magnetic technology that measured the clubface in the impact zone. It measured the face rotation, angle of attack, ball/face contact point, and speed. When we tested tour players, we noticed that the rotational function repeatedly gave us 2.5° of rotation per inch of linear movement of the heel.

His advice for the hacks to simply rotate your hands through the ball like you were screwing in a light bulb is utter nonsense.

His claim that the clubface rotation through the ball increases ball speed is utter nonsense also, the ball is only on the club face for a milisecond and the rotation would have to be around 1300 rpms to add any club speed to the ball, and that ain't happening.

Joined: November 17th, 2001, 6:19 am
AJ Bonar....studies

Studies over the last few years in USA by USPGA Professional, A.J.Bonar, clearly and irrefutably show that the clubface of all top players actually closes at the rate of 2.5 degrees every inch. Simply put, this means that the clubface rotates a full 30 degrees from 6 inches before impact to 6 inches after impact! I quote from a recent e-mail from AJ;

The first measurement I made about the amount of toe rotation was about 17 years ago, and it was done when I had a company, Digital Precision Golf, measure my own clubface to find the difference in speed between the heel and the toe. The chap that owned the company thought my interest was misplaced. He thought it would not be more than 1 mph, at best. On the day following his capture of my 5 iron shot, he called me and said the toe of my 5 iron was traveling 16.5 mph faster than the heel. This seemed to me to be more in line with what I saw on the lesson tee, when students move from the "square face" impact concept to using the dynamic, rotating clubface through impact.

In 1998, I had access to an electro-magnetic technology that measured the clubface in the impact zone. It measured the face rotation, angle of attack, ball/face contact point, and speed. When we tested tour players, we noticed that the rotational function repeatedly gave us 2.5° of rotation per inch of linear movement of the heel.

Do you not believe the actual science that Peter has pointed you to?

I think that you can learn a lot here. I know that I have.

Ham

Joined: July 12th, 2001, 12:35 am
His advice for the hacks to simply rotate your hands through the ball like you were screwing in a light bulb is utter nonsense.

His claim that the clubface rotation through the ball increases ball speed is utter nonsense also, the ball is only on the club face for a milisecond and the rotation would have to be around 1300 rpms to add any club speed to the ball, and that ain't happening.
How scientific is Bertholy?
How accurate is AJ?

I don't really agree with any of them but all of their claims can not be completely disregarded.

To me the measure of a good instructor is not how scientific are you. There are plenty of Know-it-all instructors that can't play golf or hit a ball out of their shadow themselves. The measure of a good instructor is one who can actually help his student achieve a better golf swing based on club movement even if his "Science" is completely wrong.

I talk to hundreds of AJ students and they say that his "theories" of how the club face moves helped them understand and hit the golf ball better. Can you discount that?.

Of course I am not an advocate of AJ, however, I always read and keep up with what other instructors say and do and whether the things out there are actually helping people.

Todd

Joined: July 12th, 2001, 12:35 am

Do you not believe the actual science that Peter has pointed you to?

I think that you can learn a lot here. I know that I have.

Ham
It is not about what I believe or don't believe regarding science.

I look for information that is applicable. Most of the scientific stuff (whether factual or not) has nothing to do with hitting a golf ball.

When Moe would tell me his feelings of his vertical drop, the coin drill and the all of the ways he felt when he hit a golf ball I would at first look for evidence (on video) to whether his feelings matched the reality of the club movement. Rarely did they match up however, I found his feelings to be extremely valid and useful to learning the "feeling" of proper club movement.

Moe's feelings (completely unscientific) were one million more times useful than the theories and science that gets spewed all over this forum.

You can talk about physics, rotations, inertia, centrifugal force, and all of the things that are obviously part of walking down the street and hitting a golf ball. But until you actually experience it, and achieve it, none of it means crap.

If you feel what Moe felt, you get the proper club movement reality. Is that scientific?

What would you pay to stand in Moe's body and hit a golf ball just once? What would that be worth? There is no science that can explain that or give you that experience.

I do, however, believe that you can have something very close to that experience but it is not by reading a science book or even reading this forum. (sorry Peter).

So what have I learned here?

I have learned that there are a bunch of intelligent people wasting their time on stuff that really will never give them the experience they are looking for.
I have learned that most people on this forum just want to be right for the sake of being right.
I have learned how much information is really out there (good and bad) that is actually being observed and interpreted.
I have learned that to fill my head and arm myself with more "science" is even more useless that I once considered and that all I really want to be is useful and helpful whether I am right scientifically or not.

Just to name a few.

Todd

Joined: January 14th, 2003, 11:57 pm
AJ Bonar....studies

Studies over the last few years in USA by USPGA Professional, A.J.Bonar, clearly and irrefutably show that the clubface of all top players actually closes at the rate of 2.5 degrees every inch. Simply put, this means that the clubface rotates a full 30 degrees from 6 inches before impact to 6 inches after impact! I quote from a recent e-mail from AJ;

The first measurement I made about the amount of toe rotation was about 17 years ago, and it was done when I had a company, Digital Precision Golf, measure my own clubface to find the difference in speed between the heel and the toe. The chap that owned the company thought my interest was misplaced. He thought it would not be more than 1 mph, at best. On the day following his capture of my 5 iron shot, he called me and said the toe of my 5 iron was traveling 16.5 mph faster than the heel. This seemed to me to be more in line with what I saw on the lesson tee, when students move from the "square face" impact concept to using the dynamic, rotating clubface through impact.

In 1998, I had access to an electro-magnetic technology that measured the clubface in the impact zone. It measured the face rotation, angle of attack, ball/face contact point, and speed. When we tested tour players, we noticed that the rotational function repeatedly gave us 2.5° of rotation per inch of linear movement of the heel.

OK...so the clubhead rotates through 30deg 6" before contact to 6" after. This means little in the real world, since the clubhead only has to be precisely oriented to the target line at the moment of impact, just a hair before the bottom of the swing arc, and attempting to hold off rotation with the hands causes me more disasters than just letting the hands/forearms naturally rotate through the shot.

Joined: July 12th, 2001, 12:35 am

AJ is just saying that the club rotates through impact. This is my experience and sometimes helpful to know for students who think the face should be square past the golf ball. But what I find even more important is that from this information, and from my experience, I don't believe that the club is oriented to the target line at impact. That has been my point. I believe that the club is oriented at the time of separation not impact which I believe is relevant regarding "how" the club moves into and through impact.

For those "trying" to square the face, this information is very important.

Todd

Joined: January 1st, 1970, 12:00 am
may be useful for 'feel' but there is no data to support that it is really what happens. It is fine to represent a 'feel' for instructional purposes however to represent it a what really happens is a misrepresentation. There is ample video evidence including evidence to be seen many weeks on TV that clubface rotation is varied by impact position and that beyond this there is little rotation of the clubface between impact and separation.

Peter