Sustaining the line of compression

[mandrin]

quote:Originally posted by Tom Bartlett

The earth is just a bigger ball! Let's use a bowling ball instead. Would your hinged club behave differently than a solid shaft when impacting a bowling ball?

Tom, I mentioned that sometimes one does not get far with intuitive reasoning and common sense. That is however exactly what you are trying to do with your post.

The critical parameter to consider here is the factor of time. Impact interval is very, very short, about 0.0005 secs. Now, start listing what you are capable of doing in such a very short time interval.

It is a bit like physical dimensions, some things are small, some other things much smaller yet, but eventually we reach atomic dimensions completely out of reach for our senses and understanding.

Using a golf club to hit the earth and considering it simply to be a bigger golf ball is not taking into account the type of arguments above.

The collision between a clubhead and a golf ball is a specific defined event and can readily be analyzed by elementary physics.

If you can supply me with the typical weight of a bowling ball and a coefficient of restitution than the collision of a clubhead with a bowling ball can be analyzed as another specific event.

However don’t expect to get a carry of 300 yards.

 

[Brian Manzella]

Mandrin.

What about heavy rough?

Why did SFTPS use a hinge and not a string?

Why won't you just answer Tom?

 

[mandrin]

What about heavy rough?

Brian, I try my best to be very explicit in my answers but you, with regard to posing questions, are not an example to follow. []

I have to imagine what exactly is the meaning of your question. You better tell me more explicitly what you have in mind here.

Why did SFTPS use a hinge and not a string?

The purpose of their experiments being strictly to prove the concept of the clubhead acting as a free body with regard to impact it was hence only necessary and sufficient to have a one degree of freedom hinged joint.

Why won’t you just answer Tom?

I did. Moreover I think Tom to be perfectly capable to tell me himself if my answer does not satisfy him and I will try again.

 

[Tom Bartlett]

Wait... are you saying that the hinge in their club only had one degree of travel. Now you are going to make me unpack all my stuff to find my book (packed everything for Katrina). A club bends more than one degree during a swing. How was that affecting the behavior of the club they were using. Doesn't sound like a free body. And, if the free moving club head is affected by a bowling ball then the same physics should affect any other ball no matter the size. The difference will be smaller, but same. Also, how did SFTPS swing the club? Was it just a "left arm" or was there a "body" or "right arm" supporting?

 

[mandrin]

Tom, I have to come back on your post, but for now just a remark.

The scientific research of a group of well known English scientists is seemingly regarded as not having much worth. Yet any ‘scientific’ remark in the yellow book is taken as the gospel. However Homer was a safety technician and hence not having quite the same professional qualifications. [8)]

Try to keep a bit an open mind. Ask any qualified scientist you might know and he will say the same things I am putting forward. There is no gimmick here. Simple standard physics taught everywhere on the planet in the same way, the scientific way, not just like some golfers doing biased wishful thinking.

 

[Brian Manzella]

Mandin, answer Tom's post.

And if you want to take an IQ test against Tom, I'll take Tom for a croaker.

 

[shortgamer]

Mandrin, I came to this site to learn how to hit the ball better. So tell me where all this is going. Is Brian teaching something wrong? If so lets hear it. Tell us how to hit it better through impact. If not, whats your point?

 

[Axel_WIngert]

Things are getting interesting...

Mandrin- your criticism is perfectly valid from a Physics standpoint. I have to admit that and the problem in the concept bothers me for quite a while.
BUT- there have been measurements showing that when having the hands in front of the ball- left wrist flat, one hits the ball further with the same clubhead speed. If one has a look at long hitting pros they all have their wrists flat at impact.
And even though not very scientific- it feels like I'm hitting it further when my left wrist is flat.

Now things are getting crucial...
The question is how to go on from here. So far the following two approaches have been taken:

1.Scientist group: "There are SO many gaps in Homers work! And he even wasn't a real scientist. Don't listen to that shop floor technician who even contradicted our "god"- Alaistar Chocran"

2.Non scientist, non golfing machine golfpros feeling threatend by the book: "Golf's not THAT cpomplicated. Forget about these GM-nuts. Even the scientists said that it's all wrong.

I think there are better ways. Because to me Homer Kelley was a genius. Big part of what he wrote was done intuitively. He used what was described as "intuition of an engineer- the ability to intuitively apply maths to real live situation which are too complex to be fully covered by the mathematical formalism" in my first university maths book (I'm studying Physics).

So instead of spitting on Homers work today's scientists should try to find out why the things he described are working even though his explanations may not always be 100 per cent correct. Nobody is bashing Newton- even though he wasn't totally correct either.

Axel Wingert
Dossenheimer Landstraße 50
69121 Heidelberg
Germany

 

[MizunoJoe]

quote:Originally posted by Axel_WIngert

Things are getting interesting...

Mandrin- your criticism is perfectly valid from a Physics standpoint. I have to admit that and the problem in the concept bothers me for quite a while.
BUT- there have been measurements showing that when having the hands in front of the ball- left wrist flat, one hits the ball further with the same clubhead speed.

Here's something that might bother you even more - you can have a flat left wrist two distinct ways - it can be firm or it can be loose, yet flat because the wrist bone is moving faster than the back of the hand.

 

[mandrin]

quote:Originally posted by Axel_WIngert

Things are getting interesting...

Mandrin- your criticism is perfectly valid from a Physics standpoint. I have to admit that and the problem in the concept bothers me for quite a while.
BUT- there have been measurements showing that when having the hands in front of the ball- left wrist flat, one hits the ball further with the same clubhead speed. If one has a look at long hitting pros they all have their wrists flat at impact.
And even though not very scientific- it feels like I'm hitting it further when my left wrist is flat.

Now things are getting crucial...
The question is how to go on from here. So far the following two approaches have been taken:

1.Scientist group: "There are SO many gaps in Homers work! And he even wasn't a real scientist. Don't listen to that shop floor technician who even contradicted our "god"- Alaistar Chocran"

2.Non scientist, non golfing machine golfpros feeling threatend by the book: "Golf's not THAT cpomplicated. Forget about these GM-nuts. Even the scientists said that it's all wrong.

I think there are better ways. Because to me Homer Kelley was a genius. Big part of what he wrote was done intuitively. He used what was described as "intuition of an engineer- the ability to intuitively apply maths to real live situation which are too complex to be fully covered by the mathematical formalism" in my first university maths book (I'm studying Physics).

So instead of spitting on Homers work today's scientists should try to find out why the things he described are working even though his explanations may not always be 100 per cent correct. Nobody is bashing Newton- even though he wasn't totally correct either.

Axel, there are no miracles in nature and hence hope that you subscribe to the fundamental idea that identical conditions should produce identical results. [8D]

Further more, collision of head with ball is not the same as hands alignment at impact. By throwing all things at once in the pot, as if the same, is a bit confusing. [8)]

I wonder where you see all those discussions, scientists vs non scientists? Let’s see: Chuck, no discussions, Lynn, no discussions, Brian, minimal.

Brian’s forum has 4000 members. There is hence 1 against 3999, therefore no matter of biting or spitting but rather being bitten and spit upon. Brian’s fun is when all are cracking fun / insulting that single member.

If you try to introduce some science onto a TGM forum then this is, ipso facto, without any further consideration, considered as an assault on Homer, no matter what the discussion entails.

Axel, I am curious - who and where are all those scientists you mention who are so involved in spitting on Homer’s work? IMO, scientists are showing remarkable little interest in golf.

 

[Brian Manzella]

Mandrin,

You love it, don't you?

Even my old nemisis—the late Frank Mackel—was right on this one:

"No good deed goes unpunished."

Mandrin, what I AM is a TEACHER. I just happen to be teaching golf. But, trust me, I could get a non-musician to play the drums faster than ANY 'drum instructor.' Ask Tom Bartlett.

You are TALKING, TALKING, TALKING, TALKING, but all you are saying is this:

'IT DOESN'T MATTER WHAT YOU ARE DOING DURING THE INPACT INTERVAL, BECUASE THE CLUBHEAD ACTS AS THOUGH IT WERE ATTACHED TO A STRING.'

And, I basically agree. So what's the beef?

I have told you 10000000000000000 times, I am NOT a TGM "apologist."

My feelings are VERY close to that of my dear friend Axel.

As far as I am concerned, this is a done thread. Mandrin, you win.

Next.

P.S. — But, if you are smart, and you like golf, you'll come see me and I'll get you to hit it as good as you can.

 

[mandrin]

quote:Originally posted by Tom Bartlett

Wait... are you saying that the hinge in their club only had one degree of travel. Now you are going to make me unpack all my stuff to find my book (packed everything for Katrina). A club bends more than one degree during a swing. How was that affecting the behavior of the club they were using. Doesn't sound like a free body. And, if the free moving club head is affected by a bowling ball then the same physics should affect any other ball no matter the size. The difference will be smaller, but same. Also, how did SFTPS swing the club? Was it just a "left arm" or was there a "body" or "right arm" supporting?

quote:Originally posted by brianman

Mandin, answer Tom's post.

Tom, as you can see, I have no choice, Brian really demands that I answer your question. []

Let’s say that a golfswing lasts for about 1 sec

Impact interval is 0.0005 sec

Hence for 0.9995 sec the clubhead is not busy colliding with the ball.

We are however here only concerned with that tiny interval of 0.0005 sec

During the 0.0005 sec collision interval there are very large forces acting between clubhead and ball, up to 2000 lbs.

The force a golfer can possibly add, at impact speed, is very small, a few lbs.

Now, Tom, tell me, what can you possibly do with your few lbs in that tiny interval of 0.0005 sec to compete with the existing thousands of lbs of impact force generated by the collision?

When mention is made of a clubhead acting the same as if it was a free body then, listen carefully, it is only in relation to the tiny interval of 0.0005 sec, the duration of the collision.

But, during that very small interval of 0.0005 sec, the clubhead, connected to the shaft, is behaving exactly the same as a free clubhead moving with same velocity and same trajectory.

BUT ONLY FOR THAT TINY INTERVAL 0F 0.0005 SEC.

Nevertheless, tiny as it might be, it is the moment of truth in the golf swing.

 

[mandrin]

quote:Originally posted by brianman

Mandrin,

You love it, don't you?

Even my old nemisis—the late Frank Mackel—was right on this one:

"No good deed goes unpunished."

Mandrin, what I AM is a TEACHER. I just happen to be teaching golf. But, trust me, I could get a non-musician to play the drums faster than ANY 'drum instructor.' Ask Tom Bartlett.

You are TALKING, TALKING, TALKING, TALKING, but all you are saying is this:

'IT DOESN'T MATTER WHAT YOU ARE DOING DURING THE INPACT INTERVAL, BECUASE THE CLUBHEAD ACTS AS THOUGH IT WERE ATTACHED TO A STRING.'

And, I basically agree. So what's the beef?

I have told you 10000000000000000 times, I am NOT a TGM "apologist."

My feelings are VERY close to that of my dear friend Axel.

As far as I am concerned, this is a done thread. Mandrin, you win.

Next.

P.S. — But, if you are smart, and you like golf, you'll come see me and I'll get you to hit it as good as you can.

Brian, I have had a hard time following you meanderings about this subject with time. However, I like your wits to now clearly state that you finally basically agree now with me and the English scientists.

Moreover having seen close hand the ‘ardour’ which with many adhere literally to the gospel it also takes some courage for you to make your remark re to TGM. I definitely like your gutsy attitude.

However, when you refer emphatically to ‘talking’, made me wonder what you had in mind creating this forum. The only thing you can do on a forum is ‘talking’. Is not that so?

 

[birdie_man]

Wait....

What do you agree with Brian?

...

You always have stressed "keeping the club mashing against the ball."

 

[Brian Manzella]

The point is Man-dude, is that you made your point.

"Bullet Hole through a basketball."

That's what I have taught since 1987.

Next subject, please.

 

[Tom Bartlett]

Add...I said nothing about adding anything. You must have me confused with someone else.

Let's explore Newton's third law. In a collision between two objects, both objects experience forces which are equal in magnitude and opposite in direction. Such forces cause one object to speed up and the other to slow down. While the forces are equal in magnitude and opposite in direction, the acceleration of the objects are not necessarily equal in magnitude. The acceleration of an object is dependent upon both force and MASS.

So, if a bus going 50mph hits a golf ball suspended in the air, and a little red wagon going 50mph hit a golf ball suspended in the air (they are both striking the ball with the same surface)...the bus is going to make it (the ball) go further.

My 80lb niece is going to swing a baseball bat 30mph and hit a ball on a tee, and Mark McGuire is going to swing the same bat 30mph and hit a ball off of a tee. Mark's shot goes further. Why? more mass to lesson the deceleration of the bat at separation.

Now, do the same experiment with the two of them with a golf club. Same club, same swing speed at impact. Mark's goes further.

Ah!!! now let's attach the head of the club to the grip with a string. They both go the SAME distance. Why, because there is no way to transfer their mass to the club head, IE. no shaft.

Hence my question earlier which you didn't answer. When SFTPS did their experiment did they swing the club just from the left shoulder or did they have a "right arm" or "body" to support the club?

 

[Vaako]

Could some owner of “Search for the Perfect Swing” be so kind as to post a picture showing the infamous hinged clubhead arrangement?


Vaako

 

[MizunoJoe]

quote:Originally posted by mandrin




During the 0.0005 sec collision interval there are very large forces acting between clubhead and ball, up to 2000 lbs.

The force a golfer can possibly add, at impact speed, is very small, a few lbs.

what can you possibly do with your few lbs in that tiny interval of 0.0005 sec to compete with the existing thousands of lbs of impact force generated by the collision?

You can reduce collision losses by providing a firm attachment between the clubhead and the ground via a firm/flat left wrist and a stressed shaft, and thereby maximize separation velo.

 

[mandrin]

quote:Originally posted by Tom Bartlett

Add...I said nothing about adding anything. You must have me confused with someone else.

Tom, if I understand you correctly you don’t feel that force is playing any role during impact but that it is instead the “additional” mass somehow generated by the golfer which gives additional ball departure speed. The two, however, ‘force’ and ‘mass’, are considered by many to play both a role. You say ‘mass’ is a factor but not ‘force’. Let’s see what Homer did have to say about this.

Speed (Centrifugal Pull) and Prestress (Acceleration) stiffen the Clubshaft for consistent resistance to Impact Deceleration.
Treat that “heavy” feel of “Clubhead recovery” after Impact as though it were all Impact even though the ball is actually long gone.

Homer is here both invoking force (acceleration/deceleration) and mass (heavy feel). The notions of ‘sustaining impact’, ‘keeping the club mashing against the ball’, ‘getting your weight into the ball’, ‘swing slow and deliberately’, ‘the slower you swing the harder you hit’, are part of golf since a very long time.

Tom I will briefly answer your questions but prepare a more detailed post on this subject of a possible ‘mass’ factor. I have seen your example of a vehicle hitting a golf ball, and similar ones, quite often and perhaps it is time to really explain clearly why this is not correct.


Let's explore Newton's third law. In a collision between two objects, both objects experience forces which are equal in magnitude and opposite in direction. Such forces cause one object to speed up and the other to slow down. While the forces are equal in magnitude and opposite in direction, the acceleration of the objects are not necessarily equal in magnitude. The acceleration of an object is dependent upon both force and MASS.
Correct

So, if a bus going 50mph hits a golf ball suspended in the air, and a little red wagon going 50mph hit a golf ball suspended in the air (they are both striking the ball with the same surface)...the bus is going to make it (the ball) go further.
If we assume the same coefficient of restitution for the two vehicles and respectively a weight of 1000 kg and 10,000 kg for the two vehicles than the additional departure speed obtained for the impact with the heavier vehicle will be 0.00004 %. The ball velocity increase for the heavier vehicle is hence extremely small. []

My 80lb niece is going to swing a baseball bat 30mph and hit a ball on a tee, and Mark McGuire is going to swing the same bat 30mph and hit a ball off of a tee. Mark's shot goes further. Why? more mass to lesson the deceleration of the bat at separation.
I don’t have any information on baseball bats and balls.

Now, do the same experiment with the two of them with a golf club. Same club, same swing speed at impact. Mark's goes further.
Not Correct. The collision interval is shorter than the time for the shockwave to travel from the clubhead to the butt end of the shaft. Ball is long gone before the hands become ‘aware’ of impact occurring. Saying it differently, the clubhead mass is dynamically completely decoupled from the golfer's mass during impact.


Ah!!! now let's attach the head of the club to the grip with a string. They both go the SAME distance. Why, because there is no way to transfer their mass to the club head, IE. no shaft.
Correct, but not for the reason mentioned.

Hence my question earlier which you didn't answer. When SFTPS did their experiment did they swing the club just from the left shoulder or did they have a "right arm" or "body" to support the club?
I don’t have that information. However this information is immaterial. Swinging identically with and without the small hinge is all that counts for this experiment. It is a differential type of experiment.

 

[mandrin]

quote:Originally posted by MizunoJoe

quote:Originally posted by mandrin

During the 0.0005 sec collision interval there are very large forces acting between clubhead and ball, up to 2000 lbs.

The force a golfer can possibly add, at impact speed, is very small, a few lbs.

what can you possibly do with your few lbs in that tiny interval of 0.0005 sec to compete with the existing thousands of lbs of impact force generated by the collision?

You can reduce collision losses by providing a firm attachment between the clubhead and the ground via a firm/flat left wrist and a stressed shaft, and thereby maximize separation velo.

MizunoJoe, do you have some additional arguments to try to convince me of your point of view?

During the 0.0005 sec impact interval you as a golfer are not important anymore. All the good conditions have been hopefully prepared prior to impact. The clubhead is now completely on its own to cash in on your good intentions.