Michael Finney
New
the ball kicks back on the clubhead - obviously not as much as the ball and ground do on an iron strike...
there's a picture out there that is being touted....
- Thread starter Michael Finney
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the ball kicks back on the clubhead - obviously not as much as the ball and ground do on an iron strike...
ggsjpc
New
Little Ball Before Big Ball
Hopefully, the deflection that flexes the shaft back is the ball and the ground just after.
The ball has an impact as well as the ground.
Also causes the loft of the face to decrease as well.
Hopefully, the deflection that flexes the shaft back is the ball and the ground just after.
The ball has an impact as well as the ground.
Also causes the loft of the face to decrease as well.
A Tom Wishon post to the Spinetalkers Forum
From: Tom Wishon <tww@wishongolf.com>
To: SpinetalkersForum@yahoogroups.com
Date: Tue, 06 Nov 2007 15:38:58 -0700
Subject: RE: [SpinetalkersForum] Shaft Lag
Dave, et. al.:
I did not provide those photos on the iseekgolf.com site to accompany the article I wrote. I did not see them either, other wise I would have nixed the post impact photo because that is very misleading in reference to what I believe and say about the action of the shaft BEFORE impact. Twice in my past career I had the chance to borrow a high speed camera with which I have seen the "bending forward action of the shaft" for LATE release swings and the "shaft straight at impact" for early release swings. I've yet to see a situation in which the shaft is bending backward, what I call "shaft lagging".
Going at it from the other direction with the able assistance of my engineering mentor of the past 13 yrs, it is simply not possible under
normal swing and normal shaft flex situations for a shaft to arrive at impact flexed backward. As long as the golfer maintains a wrist cock angle, and as long as the golfer maintains positive acceleration of the arm/club on the downswing, whatever flex the golfer generates at the beginning of the downswing is maintained until they start to unhinge the wrist cock angle.
Once the golfer begins to unhinge the wrist cock angle, the arms begin to slow down as the club accelerates to its top velocity. If you look at any slow motion video of a late release swing, you can see this because the club covers a whole lot of ground during which the arms don't move very far. This action is what causes the head to push the shaft to bend forward. If the wrist cock release happens early in the downswing, the shaft goes through this forward bend shape well before impact, such that it has the time to rebound backward to a straight position at impact. If the wrist cock release occurs very late, this is when the shaft arrives at impact flexed a little forward.
Another way to verify this action comes from being able to measure the clubhead velocity all the way through the downswing. With early release golfers, you see that they achieve their highest clubhead velocity at the moment the wrist cock release is fully completed - after that the club begins to slow down such that the head velocity at impact is lower than it was at the moment of their full release. Not so with late release golfers - they reach their full clubhead speed right at impact.
From all of this, we do believe that the only possible way that a golfer can have the shaft flexed backward in what we call a "shaft lag" position is if they somehow were able to reach impact without fully releasing the wrist cock angle - if this were possible for the golfer to do this without injuring themselves and without missing the ball, the fact that the arms still contain a fair amount of energy to keep their velocity would allow the possibility of the shaft still being flexed a little backwards. I've mentioned before that the only shot in the game I can think of this being possible is one of Tiger Woods' stinger shots that he can hit with a long iron or fwy wood to keep the ball really low.
While we're at this, over the past few years, we've also tried to look into this matter of "why do some golfers seem to generate more head velocity with a different shaft flex or different bend profile in the shaft design than others." Some people want to ascribe this to one shaft having a higher tip velocity than another - as if one shaft could "buggywhip" faster into impact than another.
After applying everything I know and my engineering advisors know about the physics of the action of the shaft in the swing, and after
consulting with a couple of Ph.D's in biomechanics who are also "golf science nuts", we feel the explanation is far more in the field of
biomechanics and how one body reacts to the bending action of a shaft vs how it reacts to a different bending action in a different shaft.
For golfers who have any sense of feel for the bending action of the shaft during the swing, conscious or even sub-conscious, there is no question in my mind that golfers can generate a little different swing action with one shaft design vs another. The first place this ever hit me was back when I used to spend a little more time out on the PGA Tour with players for whom I was assigned the task of designing clubs. I would see reps from the different shaft companies come around with whatever new shaft design they were pushing, trying to get the pros to hit balls on the range with a club that had their shaft in it. It always amazed me that when the pro hit the shaft and didn't like it, the pro would not hit more than two shots with the club before tossing it back to the rep and refusing to hit it anymore.
When I would probe this with the players out of curiosity to hear what it was they didn't like, it was never scientific for sure, but their
comments got me to thinking on this. Common for such a comment was, "if I kept hitting that shaft, I would have to change something to make it feel like I want my shaft to feel, and that would screw me up." This always stuck with me as we kept doing our shaft performance research over the past several years.
At any rate, and to keep this short, I think the main reason a golfer can experience very measurable differences in distance with one shaft vs another comes more from the effect the feel of the shaft has to their swing TIMING. When launch angle and spin rate are the same between two shafts but one sends the ball off at a higher clubhead speed and ball speed, it invariably comes because of the effect the feel of the shaft is so "right" for the golfer that they sub-consciously at first, but consciously as they hit more balls with the shaft, are able to "freewheel" the club through impact with a much better level of swing timing.
Anyway, still talking to my biomechanic golf nuts about conceiving of some way to test for this. But for now, after all this many years in shaft fitting, I tend to think that with some golfers, not all, it is possible for some little changes like Kempton's 2 gram change to MOI and changes in the bending feel of the shaft to automatically send the golfer into a much more FREE release with little to no manipulation, which in turn accounts for the higher clubhead and ball speed.
My 3 cents worth
TOM
From: Tom Wishon <tww@wishongolf.com>
To: SpinetalkersForum@yahoogroups.com
Date: Tue, 06 Nov 2007 15:38:58 -0700
Subject: RE: [SpinetalkersForum] Shaft Lag
Dave, et. al.:
I did not provide those photos on the iseekgolf.com site to accompany the article I wrote. I did not see them either, other wise I would have nixed the post impact photo because that is very misleading in reference to what I believe and say about the action of the shaft BEFORE impact. Twice in my past career I had the chance to borrow a high speed camera with which I have seen the "bending forward action of the shaft" for LATE release swings and the "shaft straight at impact" for early release swings. I've yet to see a situation in which the shaft is bending backward, what I call "shaft lagging".
Going at it from the other direction with the able assistance of my engineering mentor of the past 13 yrs, it is simply not possible under
normal swing and normal shaft flex situations for a shaft to arrive at impact flexed backward. As long as the golfer maintains a wrist cock angle, and as long as the golfer maintains positive acceleration of the arm/club on the downswing, whatever flex the golfer generates at the beginning of the downswing is maintained until they start to unhinge the wrist cock angle.
Once the golfer begins to unhinge the wrist cock angle, the arms begin to slow down as the club accelerates to its top velocity. If you look at any slow motion video of a late release swing, you can see this because the club covers a whole lot of ground during which the arms don't move very far. This action is what causes the head to push the shaft to bend forward. If the wrist cock release happens early in the downswing, the shaft goes through this forward bend shape well before impact, such that it has the time to rebound backward to a straight position at impact. If the wrist cock release occurs very late, this is when the shaft arrives at impact flexed a little forward.
Another way to verify this action comes from being able to measure the clubhead velocity all the way through the downswing. With early release golfers, you see that they achieve their highest clubhead velocity at the moment the wrist cock release is fully completed - after that the club begins to slow down such that the head velocity at impact is lower than it was at the moment of their full release. Not so with late release golfers - they reach their full clubhead speed right at impact.
From all of this, we do believe that the only possible way that a golfer can have the shaft flexed backward in what we call a "shaft lag" position is if they somehow were able to reach impact without fully releasing the wrist cock angle - if this were possible for the golfer to do this without injuring themselves and without missing the ball, the fact that the arms still contain a fair amount of energy to keep their velocity would allow the possibility of the shaft still being flexed a little backwards. I've mentioned before that the only shot in the game I can think of this being possible is one of Tiger Woods' stinger shots that he can hit with a long iron or fwy wood to keep the ball really low.
While we're at this, over the past few years, we've also tried to look into this matter of "why do some golfers seem to generate more head velocity with a different shaft flex or different bend profile in the shaft design than others." Some people want to ascribe this to one shaft having a higher tip velocity than another - as if one shaft could "buggywhip" faster into impact than another.
After applying everything I know and my engineering advisors know about the physics of the action of the shaft in the swing, and after
consulting with a couple of Ph.D's in biomechanics who are also "golf science nuts", we feel the explanation is far more in the field of
biomechanics and how one body reacts to the bending action of a shaft vs how it reacts to a different bending action in a different shaft.
For golfers who have any sense of feel for the bending action of the shaft during the swing, conscious or even sub-conscious, there is no question in my mind that golfers can generate a little different swing action with one shaft design vs another. The first place this ever hit me was back when I used to spend a little more time out on the PGA Tour with players for whom I was assigned the task of designing clubs. I would see reps from the different shaft companies come around with whatever new shaft design they were pushing, trying to get the pros to hit balls on the range with a club that had their shaft in it. It always amazed me that when the pro hit the shaft and didn't like it, the pro would not hit more than two shots with the club before tossing it back to the rep and refusing to hit it anymore.
When I would probe this with the players out of curiosity to hear what it was they didn't like, it was never scientific for sure, but their
comments got me to thinking on this. Common for such a comment was, "if I kept hitting that shaft, I would have to change something to make it feel like I want my shaft to feel, and that would screw me up." This always stuck with me as we kept doing our shaft performance research over the past several years.
At any rate, and to keep this short, I think the main reason a golfer can experience very measurable differences in distance with one shaft vs another comes more from the effect the feel of the shaft has to their swing TIMING. When launch angle and spin rate are the same between two shafts but one sends the ball off at a higher clubhead speed and ball speed, it invariably comes because of the effect the feel of the shaft is so "right" for the golfer that they sub-consciously at first, but consciously as they hit more balls with the shaft, are able to "freewheel" the club through impact with a much better level of swing timing.
Anyway, still talking to my biomechanic golf nuts about conceiving of some way to test for this. But for now, after all this many years in shaft fitting, I tend to think that with some golfers, not all, it is possible for some little changes like Kempton's 2 gram change to MOI and changes in the bending feel of the shaft to automatically send the golfer into a much more FREE release with little to no manipulation, which in turn accounts for the higher clubhead and ball speed.
My 3 cents worth
TOM
Michael Finney
New
i think mackenzie would agree with wishon for the most part....in his paper he says that shaft deflection affects clubhead orientation more than clubhead velocity
drewyallop
New
Michael,
Do you know in which anti-summit video Dr. Wood talks about shaft mechanics (so I don't have to troll all four episodes)?
Drew
Do you know in which anti-summit video Dr. Wood talks about shaft mechanics (so I don't have to troll all four episodes)?
Drew
Phil Rosenbaum
New
segment 1 i believe.
Brian Manzella
Administrator
The facts....simplified:
The clubhead & shaft are in a "lagging attitude" in EVERY golfer swing at some point in the downswing.
Well prior to impact, the shaft go into to a "leading attitude" and relative to the "point" of the grip, the clubhead is forward.
On shots off of the ground hit correctly, the ball strikes the clubhead with the shaft STILL IN a "leading attitude" and relative to the "point" of the grip, & the clubhead is STILL forward.
The ball slows down the clubhead down, and the grip "point" is now more inline with the clubhead, and as the ball pushes itself off of the clubface, the clubhead is pushed down slightly from the path it would have otherwise taken.
When this all results in a divot, the clubhead is severely slowed down and the grip "point" gets ahead of the clubhead again, sometimes a lot, and the shaft is now back into a "lagging attitude."
Soon after that, all of this information (feel) gets back to the golfer, who feels the RECOVERY of the "grip point" from behind the clubhead pre-impact (leading) to ahead of the clubhead (lagging). This feels HEAVY as the pressure on the back of the grip increases dramatically due to this recovery.
.....
I wish I'd have know this in 1987......
The clubhead & shaft are in a "lagging attitude" in EVERY golfer swing at some point in the downswing.
Well prior to impact, the shaft go into to a "leading attitude" and relative to the "point" of the grip, the clubhead is forward.
On shots off of the ground hit correctly, the ball strikes the clubhead with the shaft STILL IN a "leading attitude" and relative to the "point" of the grip, & the clubhead is STILL forward.
The ball slows down the clubhead down, and the grip "point" is now more inline with the clubhead, and as the ball pushes itself off of the clubface, the clubhead is pushed down slightly from the path it would have otherwise taken.
When this all results in a divot, the clubhead is severely slowed down and the grip "point" gets ahead of the clubhead again, sometimes a lot, and the shaft is now back into a "lagging attitude."
Soon after that, all of this information (feel) gets back to the golfer, who feels the RECOVERY of the "grip point" from behind the clubhead pre-impact (leading) to ahead of the clubhead (lagging). This feels HEAVY as the pressure on the back of the grip increases dramatically due to this recovery.
.....
I wish I'd have know this in 1987......
Dariusz J.
New member
This is right. If I only knew how to upload pics from my PC on this forum I'd show you the very Mr.Nelson confirming Brian's words...but since I do not know how, observe carefully this YT clip (nb. very good incl. Venturi, Nelson, Player and Palmer from various angles) in a slo-mo (e.g. on V1):
[media]http://www.youtube.com/watch?v=EyCq7E7rfcg[/media]
Hell, I do not know how to upload a YT vid either
Cheers
[media]http://www.youtube.com/watch?v=EyCq7E7rfcg[/media]
Hell, I do not know how to upload a YT vid either
Cheers
brian said he wished he knew "that" back in 1987. i would like to know, for players or students who have no concepts of "that", is that in what ways will the lack of knowledge of "that" affect a golfer?
i know my kids have absolutely no concept on what is being discussed in this thread and they are doing ok. will they do better than ok later if they know?
i know my kids have absolutely no concept on what is being discussed in this thread and they are doing ok. will they do better than ok later if they know?
Dariusz J.
New member
Of course. Noone ever more will force your kids to a ridiculously big clubshaft lean angle at impact as well as noone will tell your kids that they must keep FLW long after separation. They will have much more free hours to toy around (short game, putting, etc.) instead spending countless hours trying to catch something that's against simple physics.
Cheers
mgranato
New
A picture NEVER lies...
You guys are too much! Back when I used to fly attack choppers, I developed a way of applying tremendous lag across the blades. The envious pilots jealously labelled what I was doing as "pure flying". To this day, not many have every been able to achieve pure flying. A picture NEVER lies, so here is the proof of me applying tremendous lag across the blades...
If I could do this with chopper blades, imagine what I could do with a puny golf shaft - think about it!
Sincerely,
AirWolf
You guys are too much! Back when I used to fly attack choppers, I developed a way of applying tremendous lag across the blades. The envious pilots jealously labelled what I was doing as "pure flying". To this day, not many have every been able to achieve pure flying. A picture NEVER lies, so here is the proof of me applying tremendous lag across the blades...
If I could do this with chopper blades, imagine what I could do with a puny golf shaft - think about it!
Sincerely,
AirWolf
Interesting Dariusz. In my swing my left wrist stays relatively flat during the entire swing. With enough rotation of the clubface post impact I think the left wrist will stay flat and the right will stay bent. I don't think this is what "book litteralists" have in mind though. I pronate way too much to accomplish it. Nevertheless the point is I don't think it's against physics.
chipingguru
New
every swing creates some lag, but isnt the amount and period of time it is sustained still critical before the release interval begins and the the forward shaft lean occurs just before impact?
You guys are too much! Back when I used to fly attack choppers, I developed a way of applying tremendous lag across the blades. The envious pilots jealously labelled what I was doing as "pure flying". To this day, not many have every been able to achieve pure flying. A picture NEVER lies, so here is the proof of me applying tremendous lag across the blades...
If I could do this with chopper blades, imagine what I could do with a puny golf shaft - think about it!
Exactly.
Dariusz J.
New member
It is, Steve, no matter how better you are than me as a player. It is against physics, no matter how longer you can keep it unconsciously comparing to myself, and how long I can keep it comparing to a 20 hcper. The weight of the club tends to set a parallel relation with the lead arm at impact. However, there are two possible biophysical points of collapsing - lead elbow joint and lead wrist joint.
The first depends somehow on how much the joint is being turned in + or in -. The second, however, excludes the possibility of being invurnerable for club's inertia. Look at double pendulum diagrams. There is no limitation in the wrist joint as a whole comparing to the elbow one.
Cheers
Steve Greffen
New
Ok so maybe Kevin was right, that mgranato is pretty funny.
In all seriousness though, it is all how you want the chopper blades to feel.
In all seriousness though, it is all how you want the chopper blades to feel.
Jared Willerson
Super Moderator
I can't believe this is even being discussed in terms other than the sheer absurdity of some group believing that the shaft does not bend backwards after the shaft is parallel to the ground for the last time.
I like granato's pics.
I like granato's pics.
drewyallop
New
Thanks Phil.
Drew
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