Prestressed Shaft and Impact Deceleration

[jmessner]

I'm sure that all of the tools used in "Search for the perfect swing" were available to Homer.

The authors you quote explain their observations. I don't disagree with what they observed. However they fail to explain what causes the shaft to bend backwards. Additionally, they don't conclude what effect this has on impact. Third, they don't advocate this procedure. They have only observed it. In other words, they imply much, prove nothing. Please do me the favor of observing one more photo. Visit the section on this site named "Champions at Impact" and review Lee Trevino at impact. Then, in your own words, if you would kindly do so, explain your observations to me.

So Lee actually played the ball outside of his left foot with an iron? The picture is fuzzy, but to me this looks like a sand shot because part of his foot and the clubhead have been obscured and I would say he's already entered the sand. Great example of a flat left wrist with a 10-2-D.

BTW, some of the authors do discuss the lag situation during the swing - they are all good reads if you can get your hands on them.

[Daryl]

So Lee actually played the ball outside of his left foot with an iron? The picture is fuzzy, but to me this looks like a sand shot because part of his foot and the clubhead have been obscured and I would say he's already entered the sand. Great example of a flat left wrist with a 10-2-D.

BTW, some of the authors do discuss the lag situation during the swing - they are all good reads if you can get your hands on them.

I was wondering if you are bold enough to admit that the shaft flex has the Clubhead trailing the shaft?

[jmessner]

I was wondering if you are bold enough to admit that the shaft flex has the Clubhead trailing the shaft?

Yes, it sure does - after impact with a ball, sand or ground.

[Daryl]

Yes, it sure does - after impact with a ball, sand or ground.

Do you disagree with the following statement?

6-C-2-A. If the Pressure Point pressure that produced the initial Clubshaft flex is maintained it will maintain the flex also.

[Mike O]

I'll show a couple, but I'm looking forward to the high-speed images from Rhythm. Most video cameras take 60 fields (or 30 frames per second) and it's hard to get a good field at just before impact. I've taken a couple of images from my CSwing video analysis program and yes the bends are kind of subtle but they are there. See what you think. Scott Verplank and Zach Johnson.

I'm not saying I have the proof regarding shaft flex, or if certain things can be done or not- and certainly there are alot of factors- throwaway etc. that would influence a forward bending shaft. But the above photos of these clubshafts do not necessarily have a forward bending shaft at this point in the swing- if both of these golfers are swingers- which I believe they are- and you have the natural clubshaft "bowing up" that a swinger's shaft has, then when you view that "bowing up" i.e. that upside down "C" from the side as in these photos- then it will appear that the clubshaft is bending forward when it is not. So with so little "bending forward" - and the angle of these photo's - I would think that, that bending forward could be completely attributed to the "bowing up" of the clubshaft- which is the result of the sweetspot lining up with the line of pull/center of gravity application.

[jmessner]

Do you disagree with the following statement?

6-C-2-A. If the Pressure Point pressure that produced the initial Clubshaft flex is maintained it will maintain the flex also.

I'm sure it probably feels like this happens. All I know is that people who have spent a good deal of scientific study of the dynamic behavior of a shaft indicate that the shaft bends in a certain way during the golf swing and the bend is not constant from the start of the downswing to impact. This happens to be different than the way HK describes it in TGM and that does not cause me any pain but may for others. I have learned a lot from visiting the TGM forums and videos and reading the book and I was a low single-digit to start with. It's amazing how much I didn't know (and still don't) about performing a golf swing. Always room for more learning.....

[Mike O]

Does the Clubface 'match' the back of the left hand?

Even in a strong single action grip- the back of the left hand does not face in the same horizontal direction as the clubface does.

[Daryl]

In a 1981 GSEM Class discussion, Homer Kelley referred to two types of Clubshaft Bend for Swingers. The first -- "Acceleration Bend" -- stresses the top of the Shaft during the Start Down. During the second -- "Release Bend" -- the stress is opposite the Acceleration Bend as the toe of the Club attempts to get in line with the #3 Pressure Point.

The Hitter's stress is at the back of the Shaft and does not vary.

I guess then, that the 7Th edition may explain this. Then the existing 6-C-2-A section is no longer completely applicable to a swinger.

I'll buy new clubs with extra flexible shafts to get that added "Kick" the shaft will supply as I stop moving my hands to allow the shaft to take over through impact. Hmm? Or I can change to a Hitting stroke pattern.

[Daryl]

I'm sure it probably feels like this happens. All I know is that people who have spent a good deal of scientific study of the dynamic behavior of a shaft indicate that the shaft bends in a certain way during the golf swing and the bend is not constant from the start of the downswing to impact. This happens to be different than the way HK describes it in TGM and that does not cause me any pain but may for others. I have learned a lot from visiting the TGM forums and videos and reading the book and I was a low single-digit to start with. It's amazing how much I didn't know (and still don't) about performing a golf swing. Always room for more learning.....

Ok, you don't agree.

[jmessner]

I guess then, that the 7Th edition may explain this. Then the existing 6-C-2-A section is no longer completely applicable to a swinger.

I'll buy new clubs with extra flexible shafts to get that added "Kick" the shaft will supply as I stop moving my hands to allow the shaft to take over through impact. Hmm? Or I can change to a Hitting stroke pattern.

I would have thought so too, and if only a good shaft fitting were that simple, but I probably should have added:

Wishon, "The Search for the Perfect Golf Club", 2005
Chapter 4 Myths-
Myth #3 - "The third myth to bury is that the forward flexing of the shaft just before impact (which some people mistakenly call "buggy-whipping" or "kicking") increases the speed of the clubhead"......

I started this thread by saying I'm much more up on clubfitting than TGM (trying to change that) and that is probably evident in my posts, but I think there's opportunity for incorporating concepts from both to increase one's ability to teach and/or learn to play this game.