My Study of OBFL versus NBFL

[JustOne]

It is (almost) coincidental that the "real" ball direction is "similar" to face angle - it is not a "Given" as some of the NBFL'ers suggest or possibly imply.

Firstly the NBFL's have nothing to do with the launch angle of the ball so what is happening on the clubface pertaining to spin/loft/sliding or whatever is really of no consequence. That said is has been shown that hitting down on a ball doesn't make it launch higher, if you want that then you have to increase the angle (vector?) of loft between the face and the angle of attack... and/or increase impact speed.

I like the part you wrote that says... "if the clubhead aproaches the ball with any form of downward motion, then the friction imposed must have a (small?) component of downward momentum which is transferred to the ball,"... which is odd seeing as the ball is SUPPOSED to roll/slide (or whatever) UP the face whilst being deformed via compression If it's going UP can it also be going DOWN? or would that mean that the two forces would cancel each other and the ball would effectively 'stick' to the face?

I would think that provided there is an angle of attack that retains a positive launch angle that the ball would not go DOWN whatsoever..... all that said I'm lead to believe that the ball composition, ball cover, velocity of strike etc etc all affect the results slightly and there is no real 'control' to compare against.


I do find this video below exceptionally interesting as the ball doesn't appear to go DOWN whatsoever... it does ALMOST appear to roll up the face about 2mm however is it still in contact with the face? or are the forces within the ball, the direction it's been struck (more clubhead mass lower into the ball) and the way it re-forms after it's struck causing it to rotate?

[video=youtube;onWilRDea7A]http://www.youtube.com/watch?v=onWilRDea7A[/video]

One thing is clear from this vid... the ball doesn't roll/slide or whatever up the face like people THINK it might even with a lob wedge!! So it ain't gonna do it with LESS loft!

 

[SocketRocket]

Actually, Bob could well be in an excellent position to confirm when/if the British PGA promoted which 'laws'. Or even which ones he originally taught and if/when he changed (if he needed to).

If accuracy = nit-picking, then I'll happily plead guilty.

As for those (still) teaching OBFLs, it seems to me that there are sufficient 'modern gurus' and others that are publicising the NBFLs to ensure a fairly quick transition to the correct approach. It certainly took some time to convince the authorities/folk the truth about the universe rotating about the (flat) Earth.

(Overstating unnecessary detail = Nitpicking )= You

Bob studied for his PGA qualifications as a mature student so it was not that long ago. He has previously stated on this site that he was taught the NBFL at that time.

The OBFL are still taught by many people, I have not been refering only to the PGA. If you search the internet then you will find many, many people still explaining them. I have posted some videos showing it on this thread, Justin Rose being one.

Here is another by Luke Donald. http://www.youtube.com/watch?v=eTS87zKACSQ

 

[JustOne]

Actually, Bob could well be in an excellent position to confirm when/if the British PGA promoted which 'laws'. Or even which ones he originally taught and if/when he changed (if he needed to).

The ballflight laws were written correctly however the actual degree that the face influences the launch direction wasn't mentioned and it effectively said 'the face and path are both responsible for ball flight' so people ASSUMED that it was 50/50 and then it started getting weighted in favour of path... then before you know it a whole new idea of (wrong) instruction had reared it's ugly head!

UK instructors have been teaching the wrong stuff for 40, 50, 60+ years regardless of how it was written in the 'instruction manual'.

You can find 1000's of examples of UK instructors getting it wrong both on Youtube and their own websites. You'd hope that after the past 3 years (since Trackman showed what was really happening) some/most of them may have upped their game!... by no mean does that mean ALL though! (so it seems with Patrick's posts within this thread! )

 

[SocketRocket]

Sorry SR, but so much of this post is absolute tosh! Some of it is correct, but cannot be taken as 'truth' given how much is wrong!

I am sure you are not really sorry.

So as the leading authority on everything maybe you will enlighten us on the subject instead of making unqualified statements.

 

[Region3]

Firstly the NBFL's have nothing to do with the launch angle of the ball

Why not? The only difference to what happens on the horizontal direction is gravity isn't it? For the first split second of the ball's flight I'd say that gravity's effect was so small to be not worth worrying about.

 

[Foxholer]

The OBFL are still taught by many people, I have not been refering only to the PGA. If you search the internet then you will find many, many people still explaining them. I have posted some videos showing it on this thread, Justin Rose being one.

Certainly agree with you on this issue.

However, what do you think the likelihood of convincing the likes of Donald, Rose, Faldo and the like to say 'I was wrong and I did something I didn't realise I was doing' is?

Have you realised the difference between refraction and reflection (basic physics) yet?

 

[SocketRocket]

Have you realised the difference between refraction and reflection (basic physics) yet?

Ah Yes, My mistake. Thank's for picking that one up.

 

[JustOne]

Why not? The only difference to what happens on the horizontal direction is gravity isn't it? For the first split second of the ball's flight I'd say that gravity's effect was so small to be not worth worrying about.

I agree with you Gary about the launch conditions (ie the face and path MAY have an 85/15 ratio of sorts) however I don't see how they are remotely influenced by either the New or Old BFL's which pertain to the launch direction... and ultimately reflect on how the swing should be taught... this new discussion should be in a different thread. The impact/launch conditions off the face (vertical) haven't changed for EITHER of the BFL's... we are just understanding it better with modern technology.

 

[JustOne]

How old are you by the way, you are starting to sound rather juvenile in your mode of discussion.

..... he looks about 146 :whoo:

 

[SocketRocket]

..... he looks about 146 :whoo:

I did remove that after consideration. It was a bit rude of me.

 

[Foxholer]

Ah Yes, My mistake. Thank's for picking that one up.

How about the places where Coefficient of Restitution (not Restoration) is measured - certainly isn't generally related to the ball - normally the clubface - and replaced some time ago by a different metric - CT.

And balls don't 'spring' - they rebound. As do ball-bearings, just with different compression attributes.

As for my background, almost 40 years ago my University degree was in Physics, something I haven't used enormously since - though the computing career has ingrained a necessity to be precise. A bit personal of you to ask imo - something I seem to remember you thought was a bad thing!

If you are going to proselytise, you need to get the basic facts correct!

BTW. I'm a complete devotee to the NBFLs, so on the 'same side' really!

 

[Foxholer]

..... he looks about 146 :whoo:

Thank you Mr Pot!

Have you washed that pink top since Camberley? Or Woodhall Spa for that matter?

:whoo:

 

[JustOne]

Thank you Mr Pot!

Have you washed that pink top since Camberley? Or Woodhall Spa for that matter?

:whoo:

Ironed it ready for the Cooden meet!!!! :ears:

 

[Foxholer]

Ironed it ready for the Cooden meet!!!! :ears:

Not like me to nit-pick but that didn't answer the question.

BTW. What's an iron? I thought that was something found in a golf bag!

 

[richart]

Ironed it ready for the Cooden meet!!!! :ears:

Let's hope it rains and you have to wear your waterproofs.

 

[JustOne]

Let's hope it rains and you have to wear your waterproofs.

Is that you Rich?

 

[SocketRocket]

How about the places where Coefficient of Restitution (not Restoration) is measured - certainly isn't generally related to the ball - normally the clubface - and replaced some time ago by a different metric - CT.

And balls don't 'spring' - they rebound. As do ball-bearings, just with different compression attributes.

As for my background, almost 40 years ago my University degree was in Physics, something I haven't used enormously since - though the computing career has ingrained a necessity to be precise. A bit personal of you to ask imo - something I seem to remember you thought was a bad thing!

If you are going to proselytise, you need to get the basic facts correct!

BTW. I'm a complete devotee to the NBFLs, so on the 'same side' really!

Good to hear we agree on something then.

proselytise: isn't that to do with religion and differing faiths? Anyhow its not important.


Regarding your objections to my comments, I refer you to the following definitions:

Spring.

Spring:
The resilience of a body recovering its former state by it's elasticity

Restoration:

Restore: To return to original state.

I think the terms were quite explanatory and apt for the point made.

I am finding this kind of discussion with you rather pointless and demeaning to the subject under discussion. You would make a better contribution by giving your own opinions rather than making some kind of crusade in belittling mine.

 

[Foxholer]

proselytise: isn't that to do with religion and differing faiths? Anyhow its not important.

Pretty appropriate here - and it's not solely religious.

I am finding this kind of discussion with you rather pointless and demeaning to the subject under discussion.

Them make sure your terms are correct, as getting them wrong, or using spurious ones, demeans your argument!

Refraction/Reflection you've admitted was wrong.

Can you show any link to Coefficient of Restoration involving golf?

And what I suspect you meant, Coefficient of Restitution is primarily about club heads - and the 'trampoline effect', not balls and ball flights!

And I did post, many pages ago, that the entire topic was mis-titled. It should have been 'Understanding' not 'Study'. Though there wasn't much of either from/by/of the OP-er imo!

 

[SocketRocket]

Pretty appropriate here - and it's not solely religious.


Them make sure your terms are correct, as getting them wrong, or using spurious ones, demeans your argument!

Refraction/Reflection you've admitted was wrong.

Can you show any link to Coefficient of Restoration involving golf?

And what I suspect you meant, Coefficient of Restitution is primarily about club heads - and the 'trampoline effect', not balls and ball flights!

And I did post, many pages ago, that the entire topic was mis-titled. It should have been 'Understanding' not 'Study'. Though there wasn't much of either from/by/of the OP-er imo!

Fair enough but make sure you are word perfect in future.

 

[sev112]

Gary / James - yes i think you are not far off there.
The vid clip of james is interesting
I will look to see if i can find on t'interweb a clip of a 6 iron (say) or a club with a downward path at impact - the lob wedge clip is horizontal (possibly even rising) at impact.

Today, back in experiemental mode in teh hall again but using stripey sponge balls off the hardwood floor. i slid my U wedge along the floor (to ensure a horizontal attack) and observed quite noticeable backspin and launch. I then slid the club down a tray at about circa 5-10 degrees, placed to try and ensure that the club hit under the equator.
I definitely observed a much lower laucnh angle, and for what it's worth, felt more resistance on impact.

havent worked that all out yet - when i've had enough wine i'll have a think about it