A well-timed flip

[carrera]

How does it compare to the 'ideal' strike

One of the guys in my Sunday morning group is a pretty good player...good driver and putter...and usually shoots in the mid-upper 70's. His iron shots are "adequate" but he never takes much of a divot except with short irons, and when you see him hit mid and long irons the impact and ballflight never look like that of a low handicap player. He has a flip in his swing but he's timed it well since he's been playing for a long time. He complained after the round that he saw some Tiger and Dustin Johnson slo-mo's from the Open where he saw them hit down on the ball and take a divot even with long irons (and TW with a 3 wood).

The other morning we finished our round quick and had time for a small bucket of balls afterward and I spent some time with him trying a move with a less of a flip, and my rationale was that with less timing and effort required he could hit the ball more solidly and likely farther with all his clubs, even the driver. I also said it would help with hitting out of the rough.

He hit a bunch of shots with what seemed to be less flip, but every time we did a distance comparison of "flip vs no flip", the flip shot went a bit farther for him. It was only a small bucket so the experiment ended there.

A couple of things were probably at play...hitting with a flip off a mat can be successful, and there was some bias involved because for all I know he wanted the flip swings to go farther so he could justify not changing his swing. And maybe his non-flip swings weren't as non-flip as we thought.

He's an engineer, so are there some physics I could drop on him to convince him that he's not really gaining clubhead speed with a flip? Or is he, and he's just successful on occasion because he's timed it so well from practice and habit, and so a forward leaning shaft would just give him more consistency if not distance?

I'm a poet not an engineer so let me know if the equations are on my side, or not. :rolleyes:

[iteachgolf]

as soon as the club head passes the hands it is slowing down. That being said you do not need a ton of shaft lean at impact to hit solid shot. Whenever you try something new you will tend to think about it more and slow down to accomplish it so distance initially may not improve is speed goes down to accomplished the desired result.

[bpark1210]

[quote name='carrera' date='22 June 2010 - 10:11 PM' timestamp='1277269873' post='2527496']
He's an engineer, so are there some physics I could drop on him to convince him that he's not really gaining clubhead speed with a flip? Or is he, and he's just successful on occasion because he's timed it so well from practice and habit, and so a forward leaning shaft would just give him more consistency if not distance?

I'm a poet not an engineer so let me know if the equations are on my side, or not.
[/quote]

[size=2]It's not all about club head speed to get the ball moving. If he's a flipper he probably doesn't compress the ball to his maximum capabilities. You can let your friend know the better he can hit down and compress the ball the more ball speed/distance he'll gain out of the ball. Not to mention get that penetrating flight[/size]

[carrera]

[quote name='iteachgolf' date='22 June 2010 - 10:23 PM' timestamp='1277270606' post='2527514']
as soon as the club head passes the hands it is slowing down. [/quote]

That's what he needs to hear...any idea what the physics concept would be to put that in textbook form?

[happyroman]

[quote name='carrera' date='23 June 2010 - 11:39 AM' timestamp='1277311165' post='2528183']
[quote name='iteachgolf' date='22 June 2010 - 10:23 PM' timestamp='1277270606' post='2527514']
as soon as the club head passes the hands it is slowing down. [/quote]

That's what he needs to hear...any idea what the physics concept would be to put that in textbook form?
[/quote]

Sir Isaac Newton has provided us with the most basic formula in physics, F = ma (force = mass x acceleration). Distance is directly related to the force imparted to the ball. If the club head passes the hands prior to impact, it is slowing down, and by definition, cannot be accelerating. Therefore, the decelerating club head cannot strike the ball with as much force as an accelerating club head, regardless of the speed at which it is traveling. A ball struck with less force will not travel as far.

I'm sure there are other factors as well, such as the amount of backspin applied due to the downward strike applied when the hands lead the club head at impact. For most shots, more backspin will result in more height, longer carry time, and greater distance.

[juststeve]

Actually the applicable formula is kinetic energy equals mass times velocity squared. What counts is the mass and velocity of the club at impact. Acceleration in the full swing doesn’t matter which is good since no one is accelerating at the moment of impact. Good players decelerate less than poor players but no one accelerates. At a given velocity the ball doesn’t know acceleration from deceleration.

Now as to divot taking great golfers, Nelson, Nicklaus and Watson took little or no divot with long or mid irons. A divot should be looked upon as a necessary evil, better to take a bit of turf after impact than to hit the ground before impact.

Finally, compressing the ball requires hitting it solid, not trapping it against the turf. Good players compress the ball with a driver off a tee. Taking turf is not required.

Steve

[mister2cool]

[quote name='juststeve' date='23 June 2010 - 02:58 PM' timestamp='1277319489' post='2528448']
Acceleration in the full swing doesn't matter which is good since no one is accelerating at the moment of impact. Good players decelerate less than poor players but no one accelerates. At a given velocity the ball doesn't know acceleration from deceleration.
[/quote]

I find this hard to believe. What about the woosh sound that happens after impact position when you are taking practice swings? Isn't that caused by higher speed?

[happyroman]

[quote name='juststeve' date='23 June 2010 - 01:58 PM' timestamp='1277319489' post='2528448']
Actually the applicable formula is kinetic energy equals mass times velocity squared. What counts is the mass and velocity of the club at impact. Acceleration in the full swing doesn't matter which is good since no one is accelerating at the moment of impact. Good players decelerate less than poor players but no one accelerates. At a given velocity the ball doesn't know acceleration from deceleration.

Now as to divot taking great golfers, Nelson, Nicklaus and Watson took little or no divot with long or mid irons. A divot should be looked upon as a necessary evil, better to take a bit of turf after impact than to hit the ground before impact.

Finally, compressing the ball requires hitting it solid, not trapping it against the turf. Good players compress the ball with a driver off a tee. Taking turf is not required.

Steve
[/quote]

I'm not sure if you're correct that the clubhead is not accelerating at impact, but I'll take your word for it until I can find an authoritative source of information. However, my original point is still applicable, since acceleration is measured by the rate of change in speed, whether becoming faster or getting slower. A clubhead that decelerates less will still impart greater force to the ball.

For anyone who is interested in the topic of acceleration, there are some interesting posts on the Smash Golf Blog, which is devoted to Mike Austin. Here's a link.

[url="http://smashgolf.wordpress.com/category/acceleration/"]http://smashgolf.wordpress.com/category/acceleration/[/url]

[juststeve]

Perhaps we can clear up the velocity vs. acceleration question like this. Imagine a club head traveling at a constant speed of 100 mph. Its velocity is known and since it is constant the acceleration of the club head is zero. If acceleration were the proper variable the 100 mph club head would strike the ball with zero force. Does anyone think that is the case?

Steve

[acegolfer]

[quote name='juststeve' date='23 June 2010 - 02:58 PM' timestamp='1277319489' post='2528448']
Actually the applicable formula is kinetic energy equals mass times velocity squared. What counts is the mass and velocity of the club at impact. Acceleration in the full swing doesn't matter which is good since no one is accelerating at the moment of impact. Good players decelerate less than poor players but no one accelerates. At a given velocity the ball doesn't know acceleration from deceleration.

Now as to divot taking great golfers, Nelson, Nicklaus and Watson took little or no divot with long or mid irons. A divot should be looked upon as a necessary evil, better to take a bit of turf after impact than to hit the ground before impact.

Finally, compressing the ball requires hitting it solid, not trapping it against the turf. Good players compress the ball with a driver off a tee. Taking turf is not required.

Steve
[/quote]

+1

[DaveLeeNC]

FWIW, the 'dwell time' (amount of time that the clubhead is in contact with the ball at impact) is around 1/2 msec. Accelerating/decelerating - over 1/2 msec it doesn't matter. The force required to accelerate a golf ball from 0 mph to 150 mph in 1/2 msec is over 1000 pounds. You can't do that "through a golf shaft" - it is WAY too flexible.

For all practical purposes the clubhead (at impact) is a free body not connected to anything (reference Theodore Jorgenson "The Physics of Golf" plus just plain old high school physics).

dave

[ChristianT]

[quote name='DaveLeeNC' date='23 June 2010 - 07:13 PM' timestamp='1277334815' post='2528824']FWIW, the 'dwell time' (amount of time that the clubhead is in contact with the ball at impact) is around 1/2 msec. Accelerating/decelerating - over 1/2 msec it doesn't matter. The force required to accelerate a golf ball from 0 mph to 150 mph in 1/2 msec is over 1000 pounds. You can't do that "through a golf shaft" - it is WAY too flexible. For all practical purposes the clubhead (at impact) is a free body not connected to anything (reference Theodore Jorgenson "The Physics of Golf" plus just plain old high school physics).

dave[/quote]

+1. If we think of the clubhead as a free body, then we can solve for the energy transfer between the club and ball using the law of conservation of momentum. The sum of the momentums (mass * velocity) of the ball and club before impact must equal the sum of their momentums after impact (actually the sum after impact will be a little less due to energy lost to heat, friction, etc... but it is a pretty good approximation). So it is really the velocity of the club at impact that matters.[quote][quote]as soon as the club head passes the hands it is slowing down.[/quote]
That's what he needs to hear...any idea what the physics concept would be to put that in textbook form?[/quote]The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point.

[DaveLeeNC]

[quote name='ChristianT' date='23 June 2010 - 07:49 PM' timestamp='1277336950' post='2528875']
[quote name='DaveLeeNC' date='23 June 2010 - 07:13 PM' timestamp='1277334815' post='2528824']FWIW, the 'dwell time' (amount of time that the clubhead is in contact with the ball at impact) is around 1/2 msec. Accelerating/decelerating - over 1/2 msec it doesn't matter. The force required to accelerate a golf ball from 0 mph to 150 mph in 1/2 msec is over 1000 pounds. You can't do that "through a golf shaft" - it is WAY too flexible. For all practical purposes the clubhead (at impact) is a free body not connected to anything (reference Theodore Jorgenson "The Physics of Golf" plus just plain old high school physics).

dave[/quote]

+1. If we think of the clubhead as a free body, then we can solve for the energy transfer between the club and ball using the law of conservation of momentum. The sum of the momentums (mass * velocity) of the ball and club before impact must equal the sum of their momentums after impact (actually the sum after impact will be a little less due to energy lost to heat, friction, etc... but it is a pretty good approximation). So it is really the velocity of the club at impact that matters.as soon as the club head passes the hands it is slowing down.[/quote]

Conservation of momentum is conservation of momentum, independent of energy losses (a different issue).

When you apply conservation of momentum and and "the COR equation", you get the following (for a club with zero loft).....

VB = (COR+1)*MC*VC/(MB+MC)=(COR+1)*VC/(1+MB/MC)

VB - final ball velocity
COR - Coefficient of Restitution
MC - mass of the clubhead
MB - mass of the ball
VC - velocity of the clubhead just before impact

dave

[ChristianT]

Conservation of momentum is conservation of momentum, independent of energy losses (a different issue).

 

Ahh... yes. You are right. The cobwebs are starting to clear... It's been a while since I have looked at this stuff.

[mister2cool]

Holy smokes.. my brain is on fire!!

[hbear]

Maybe I missed it, but your buddy shoots in the 70s consistantly meaning he more than likely a lower single digit player...

Obvious question is, why bother trying to "fix" something that is working for him.
Don't get me wrong, I'm a BIG proponant for improving, but the sheer TIME required (I believe Mike Weir said it took him a couple years to adjust to swing changes he had made earlier in his career) to make AND trust major swing changes just might not be worth it for your friend.

Lets face it we ALL have nuances and odds and sods in our swings/play that we simply have learnt to play for.
Yes we can fix and improve those things, but a)at what cost, and b) how much of a difference will it really make.

I play with +2/+3s that aim their putter a little right of their real target line and hit slight pulls to get their ball on line. They play for it, and putt VERY well. Sure they "could" fix it, but it's honestly not worth the time nor effort as thier end result is that they are rolling their ball along their intended line....which isn't going to change with "fixing" their flaw.

Same arguement can be made on the swing. I agree that a more fundamentally sound swing helps, but if what he's doing is repeatable and playable....is it really the "x" factor that is keeping him from getting down to scratch? or is it putting/short game that is doing that? Is hitting one less club into the green the dealbreaker for him? or it really not going to make much of a difference in the big picture?

Things to think about.

[Matt1960]

Quote ChristianT
"The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point. "


But why is this the case?
I can get into address position and move the club past my hands by flipping or rotation without my arms moving. This is muscular effort of the hands and forearms that have moved the club.
Why could this not happen during the swing?

[rlskinne]

I think the "flip" you're talking about is similar to the supination Hogan talks about in his book. Maybe thinking about it in those terms will help re-engineer the move.

[tdeutmeyer]

I have been playing for 28yrs with a flip and have not been above a 5 handicap for many years until now. I wanted to have more consistent impacts and not rely on timing, so I started changing things last year. The result- I'm playing my worst golf ever....

[ChristianT]

Quote ChristianT

"The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point. "

 

 

But why is this the case?

I can get into address position and move the club past my hands by flipping or rotation without my arms moving. This is muscular effort of the hands and forearms that have moved the club.

Why could this not happen during the swing?

 

Yes, I was thinking about this last night when I was supposed to be sleeping . You are right, the muscles in the forearm can move the club head after it passes the hands. My guess is, though, that you can't make this move fast enough to apply pressure when the clubhead is moving 90mph. Likely if you are trying to muscle it at that speed you will end up slowing the club down. I have no proof of that whatsoever, though...

 

Maybe I missed it, but your buddy shoots in the 70s consistantly meaning he more than likely a lower single digit player...

 

I agree with this. All of this physics stuff may just screw your buddy up. It seems to me the main disadvantage of a flip is that such precise timing is required to get consistent contact. If he already times it very well and plays good golf it may not be worth messing with.

[Matt1960]

Quote ChristianT

"The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point. "

 

 

But why is this the case?

I can get into address position and move the club past my hands by flipping or rotation without my arms moving. This is muscular effort of the hands and forearms that have moved the club.

Why could this not happen during the swing?

 

Yes, I was thinking about this last night when I was supposed to be sleeping . You are right, the muscles in the forearm can move the club head after it passes the hands. My guess is, though, that you can't make this move fast enough to apply pressure when the clubhead is moving 90mph. Likely if you are trying to muscle it at that speed you will end up slowing the club down. I have no proof of that whatsoever, though...

 

Maybe I missed it, but your buddy shoots in the 70s consistantly meaning he more than likely a lower single digit player...

 

I agree with this. All of this physics stuff may just screw your buddy up. It seems to me the main disadvantage of a flip is that such precise timing is required to get consistent contact. If he already times it very well and plays good golf it may not be worth messing with.

 

The big problem is trying to combine physics with the human body and its movements. Yes some of it applies, but its too easy to think of ourselves as machines with passive hinges, elastic muscles etc..

 

As it happens, I dont think flipping loses a great deal of CHS, but its the quality and consistency of the strike with the irons that really suffers. Flippers are sometimes quite good drivers of the ball.

[happyroman]

[quote name='juststeve' date='23 June 2010 - 05:58 PM' timestamp='1277333897' post='2528798']
Perhaps we can clear up the velocity vs. acceleration question like this. Imagine a club head traveling at a constant speed of 100 mph. Its velocity is known and since it is constant the acceleration of the club head is zero. If acceleration were the proper variable the 100 mph club head would strike the ball with zero force. Does anyone think that is the case?

Steve
[/quote]

This is getting interesting and I am being forced to learn a lot. Apparently, there is a different formula for acceleration when considering the circular motion, such as in a golf swing. Here it is:


[b]Acceleration Formulas[/b]


There are a few. The most famous is [b]a = F/m[/b], where [b][i]F[/i][/b] is the net force applied to a mass, [b]m[/b]. Acceleration is also the change in velocity, (Delta-V), divided by the change in time, (Delta-t). So, [b]a =[/b] [b]Δ[/b][b]v/[/b][b]Δ[/b][b]t[/b].


For example, if an object's velocity changes from 10 meters per second to 20 meters per second in five seconds, its acceleration is (20-10)/5 = 2 meters per second per second, or 2 meters per second squared (m/s[sup]2[/sup]).
[b]
[/b]
[b]For circular motion[/b], centripetal acceleration is v[sup]2[/sup]/r, where [b]v[/b] is the linear velocity of the rotating object and [i][b]r[/b][/i] is the radius of its circular path.


In my original post, I used F = ma because it is a relatively simple concept, though not necessarily the most applicable. After re-reading a portion of Joe Dante's excellent book, [i]Four Magic Moves to Winning Golf[/i], I was reminded that a better scientific explanation has to do with the Conservation of Angular Momentum (COAM). I won't bore anyone here further. If anyone is interested, they can get Dante's book or do a Google search.

[KMeloney]

[quote name='Matt1960' date='24 June 2010 - 06:57 AM' timestamp='1277377077' post='2529608']
Quote ChristianT
"The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point. "


But why is this the case?
I can get into address position and move the club past my hands by flipping or rotation without my arms moving. This is muscular effort of the hands and forearms that have moved the club.
Why could this not happen during the swing?
[/quote]

I think I have the same question...

If the hands accelerate the club, and the clubhead passes the hands, then I can see where the hands are no longer supplying power to the clubhead -- IF the hands and clubhead were simply traveling DOWN THE LINE together. But, since the club is wrapping AROUND the body, can't the clubhead travel faster past the hands if the hands begin to trace a TIGHTER CIRCLE?

(This isn't a rhetorical question. I have no idea what the answer is. But it seems to me that club could continue at least at the same speed if the hands pull in on a tighter arc...)

[DaveLeeNC]

Quote ChristianT

"The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point. "

 

 

But why is this the case?

I can get into address position and move the club past my hands by flipping or rotation without my arms moving. This is muscular effort of the hands and forearms that have moved the club.

Why could this not happen during the swing?

 

Yes, I was thinking about this last night when I was supposed to be sleeping . You are right, the muscles in the forearm can move the club head after it passes the hands. My guess is, though, that you can't make this move fast enough to apply pressure when the clubhead is moving 90mph. Likely if you are trying to muscle it at that speed you will end up slowing the club down. I have no proof of that whatsoever, though...

 

Maybe I missed it, but your buddy shoots in the 70s consistantly meaning he more than likely a lower single digit player...

 

I agree with this. All of this physics stuff may just screw your buddy up. It seems to me the main disadvantage of a flip is that such precise timing is required to get consistent contact. If he already times it very well and plays good golf it may not be worth messing with.

 

A reasonable model for a golf swing is the Tribuchet (catapult) - see

. The problem with trying to apply torque with the wrists at/near impact is that any 'helpful torque' that the wrists apply to the shaft near impact also applies an equal unhelpful torque on the arms (slowing them down). Of course your body is well planted on a pretty solid foundation (the earth) and can help overcome this 'unhelpful torque'. But it does get quite complicated (either analytically or in practice) and seems to be mostly unhelpful in the general case.

 

dave

[Matt1960]

Quote ChristianT

"The reason the clubhead is slowing down after it passes the hands is that there are only two things applying force to the clubhead - the golfer and gravity. When the clubhead passes the hands, it is going faster than the hands so they can no longer be supplying power. It has also bottomed out so is travelling against gravity at that point. "

 

 

But why is this the case?

I can get into address position and move the club past my hands by flipping or rotation without my arms moving. This is muscular effort of the hands and forearms that have moved the club.

Why could this not happen during the swing?

 

Yes, I was thinking about this last night when I was supposed to be sleeping . You are right, the muscles in the forearm can move the club head after it passes the hands. My guess is, though, that you can't make this move fast enough to apply pressure when the clubhead is moving 90mph. Likely if you are trying to muscle it at that speed you will end up slowing the club down. I have no proof of that whatsoever, though...

 

Maybe I missed it, but your buddy shoots in the 70s consistantly meaning he more than likely a lower single digit player...

 

I agree with this. All of this physics stuff may just screw your buddy up. It seems to me the main disadvantage of a flip is that such precise timing is required to get consistent contact. If he already times it very well and plays good golf it may not be worth messing with.

 

A reasonable model for a golf swing is the Tribuchet (catapult) - see

. The problem with trying to apply torque with the wrists at/near impact is that any 'helpful torque' that the wrists apply to the shaft near impact also applies an equal unhelpful torque on the arms (slowing them down). Of course your body is well planted on a pretty solid foundation (the earth) and can help overcome this 'unhelpful torque'. But it does get quite complicated (either analytically or in practice) and seems to be mostly unhelpful in the general case.

 

dave

 

 

One of the problems with a lot of flippers is that they have learnt to stall the torque of the rotation of the arms through impact, in an attempt to either square the face, or extend the left arm away from the body to look like what they think is the correct position.

If this were the case, then some re-education might be necessary.

This cannot be totally explained through physics, which relies on properly working hinges etc...

The Trebuchet will only work if the mechanical componants are sound.

[caryk]

[quote name='carrera' date='23 June 2010 - 12:39 PM' timestamp='1277311165' post='2528183']
[quote name='iteachgolf' date='22 June 2010 - 10:23 PM' timestamp='1277270606' post='2527514']
as soon as the club head passes the hands it is slowing down. [/quote]

That's what he needs to hear...any idea what the physics concept would be to put that in textbook form?
[/quote]
Something that hasn't been mentioned here is that when you flip, you actually [b]increase[/b] the loft of the club rather then decrease (deloft) it. That's why the trajectory for scratch and tour players looks so much different than higher handicappers (see diagram below). Really good players compress the ball with hands leading the clubhead through impact so that they effectively turn an 8-iron into a 7 or even 6-iron at impact. They get far more distance because the ball starts out on a more penetrating ball flight that peaks late and then falls to the ground. In contrast, when you flip, you inadvertently add loft to whatever club you're using (i.e. 8-iron becomes a 9-iron) which decreases distance because it produces a shot that usually goes higher but peaks much earlier before it falls.

That's why "hands ahead" and "forward shaft lean" have always been characteristics of really good players. As iteach said, once you flip, the clubhead is slowing down AND adding loft at impact.

[juststeve]

Delofting the club at impact creates the illusion of extra distance, but it is just an illusion. Almost anyone can deloft an eight iron and make it a six iron, but almost no one can deloft their three iron to the same degree and still get the ball in the air. Squeezing more distance out of the short irons doesn’t help unless you can keep consistent adequate distance gaps throughout the set. Maybe that’s why I see guys hit their eight iron a long way and never take a long iron out of the bag.

Steve

[carrera]

[quote name='hbear' date='23 June 2010 - 11:16 PM' timestamp='1277360203' post='2529508']
Maybe I missed it, but your buddy shoots in the 70s consistantly meaning he more than likely a lower single digit player...
Obvious question is, why bother trying to "fix" something that is working for him?
[/quote]

Yeah, he might decide it isn't worth it, but he's an obsessive nut who might very well decide to do it.

He scores well but he is one of the best putters I've ever seen...his old Taylor Made putter has a wear mark on the sweet spot from pure contact (you can imagine how many putts he's hit pure in order to make a wear mark on a putter!). He is also a good driver, and pretty decent with medium length pitches (40-80 yd stuff). His iron and fairway wood game is not nearly at the level of the rest of his game....not even close. He is terrible from the rough.

[tm22721]

The visual that I was given recently...throwing the butt of the club directly at the ball as if it were a javelin...with abandon and trust...preserving maximum lag.

[Mward2002]

"The visual that I was given recently...throwing the butt of the club directly at the ball as if it were a javelin...with abandon and trust...preserving maximum lag. "

Wouldn't that just make your downswing that much steeper? Hard to control distance, spin, trajectory that way would it not?