Whippy shafts

[mandrin]

Some musings on flexible shafts

A torsionally very stiff but otherwise very flexible shaft could be a possible answer for those who can’t muscle the ball 300 yards.

 

[Bronco Billy]

Yippee!!!! Mandrins Back

 

[Dariusz J.]

Great article !
Some of the folks on Tom Wishon's Forum are now experimenting with heavier A-flex shafts with less torque, thus, similar concept as yours. Results are more than promising so far - higher SS and no significant loss of accuracy.

IMHO, what is missing here is veryfying where should be the bend point of such a shaft located. There are shafts with most flexible mid-section or most flexible tip-section. I am not sure what type od shaft you have taken as exemplary to your studies, but judging from diagrams they look more as mid-section flexible shafts. Perhaps you could revert to your study and analyze 2 scenarios with 2 different bend points.

BTW, you should be visiting Wishon Forum on regular basis, Mandrin - with your knowledge you could bring a flesh light to many subjects.

Cheers

 

[Bronco Billy]

Great article !
Some of the folks on Tom Wishon's Forum are now experimenting with heavier A-flex shafts with less torque, thus, similar concept as yours. Results are more than promising so far - higher SS and no significant loss of accuracy.

IMHO, what is missing here is veryfying where should be the bend point of such a shaft located. There are shafts with most flexible mid-section or most flexible tip-section. I am not sure what type od shaft you have taken as exemplary to your studies, but judging from diagrams they look more as mid-section flexible shafts. Perhaps you could revert to your study and analyze 2 scenarios with 2 different bend points.

BTW, you should be visiting Wishon Forum on regular basis, Mandrin - with your knowledge you could bring a flesh light to many subjects.

Cheers

Hi There

I Think what's Missing Here is a Friggen Golf Ball.... Sure as Hell Looks Good on Paper..... Let's Build It.....

Cheers

 

[nmgolfer]

Hi There

Sadly I must raise the BS flag once again. This analysis strikes me as wrong... just plain wacky really. Mandrin would have us believe a flexible beam with a mass on the end would contort as shown in figure 3 as the pendulum swings under the influence of gravity. Furthermore he would have us believe this "shaft deflection" results in the mass at the end having 29% more kinetic energy when it reaches the bottom (than the stiff shafted counterpart). I dispute those findings.

Taken to the extreme, it is not hard to imagine a mass at the end of a string. Wouldn't that be the ultimate flexible beam... a nearly massless string? What happens when a mass at the end of a taut string is released from a horizontal position as shown in Mandrins diagram? Does it contort as shown in figure 3a? No it does not contort; the string remains taut. Try this yourself at home.

The mechanics of pendulums (both simple such as mass at the end of a massless string and physical or "real" pendulums having distributed mass) are discussed in every first year physics text. T or period = 2pi(I/k')^.5 Kinetic energy is also well defined (mv^2)/2. Assuming there are no losses (aerodynamic drag or friction at the pivot) the mass at the end of the pendulum will have identical kinetic energy when it reaches vertical regardless whether the its connected to a massless string (i.e. flexible... whippy tempomaster shaft) or a super heavy superstiff steel shaft. v = (2gh)^.5 => E = m g h where h is the height if falls... in otherwords... shaft length. This simple principle is called "conservation of energy".

 

[Jim Kobylinski]

whether or not it is possible to increase swing speed with a softer flex shaft, you have to figure in launch conditons or else all that extra speed won't necessarily make the ball go any further.

I can swing an A-flex shaft faster than my X but because of the face conditions at impact, it goes shorter.

 

[Bronco Billy]

Yippee!!!! nmgolfers Back

 

[puttmad]

Surely the basic concept of this experiment is wrong?...
The clubhead doesn't simply "drop" during the golfswing, it is influenced by the hands, not just gravity.
PO is not a fixed position, as is stated, and the movement of PO in a real swing influences the velocity and behaviour of the head end..
Also, even if the experiment were correct, the flexible shaft could not bend without input from the PO end. The head would lead. So all things being equal, both flexi and rigid assemblies, would reach the "bottom" at the same time (normal pendulum effect with no kicking of the shaft), so no increasee in acceleration with the flexi-shaft...

 

[mandrin]

Flag person looking for job

Hi There

Sadly I must raise the BS flag once again. This analysis strikes me as wrong... just plain wacky really. Mandrin would have us believe a flexible beam with a mass on the end would contort as shown in figure 3 as the pendulum swings under the influence of gravity. Furthermore he would have us believe this "shaft deflection" results in the mass at the end having 29% more kinetic energy when it reaches the bottom (than the stiff shafted counterpart). I dispute those findings.

Taken to the extreme, it is not hard to imagine a mass at the end of a string. Wouldn't that be the ultimate flexible beam... a nearly massless string? What happens when a mass at the end of a taut string is released from a horizontal position as shown in Mandrins diagram? Does it contort as shown in figure 3a? No it does not contort; the string remains taut. Try this yourself at home.

The mechanics of pendulums (both simple such as mass at the end of a massless string and physical or "real" pendulums having distributed mass) are discussed in every first year physics text. T or period = 2pi(I/k')^.5 Kinetic energy is also well defined (mv^2)/2. Assuming there are no losses (aerodynamic drag or friction at the pivot) the mass at the end of the pendulum will have identical kinetic energy when it reaches vertical regardless whether the its connected to a massless string (i.e. flexible... whippy tempomaster shaft) or a super heavy superstiff steel shaft. v = (2gh)^.5 => E = m g h where h is the height if falls... in otherwords... shaft length. This simple principle is called "conservation of energy".

nmgolfer, it is a pity but it isn’t even amusing anymore to see you again show your inaptitude to simply read a post or think about its content a bit coherently.

My first reaction was to quickly save your post to safeguard against another hasty deletion, due to obvious errors, it becoming a habit.

Your allusions to pendulums and conservation of energy are not pertinent. It is again obvious that you are stuck with high school physics and simply struggling to get maximum mileage out of it.

The simple truth is that you are clearly showing again being totally unaware of the dynamics of kinetic chains, specifically the interaction of linked segments.

Furthermore if you had really looked at my post instead of hastily posting nonsense you would have noticed the kinetic energy being equal at the bottom.

If colleagues read your post and the security guard promptly escorts you to the front door, there are certainly jobs available, using your speciality - “flagging”- to signal traffic, repairing roads.

 

[mandrin]

Great article !
Some of the folks on Tom Wishon's Forum are now experimenting with heavier A-flex shafts with less torque, thus, similar concept as yours. Results are more than promising so far - higher SS and no significant loss of accuracy.

IMHO, what is missing here is veryfying where should be the bend point of such a shaft located. There are shafts with most flexible mid-section or most flexible tip-section. I am not sure what type od shaft you have taken as exemplary to your studies, but judging from diagrams they look more as mid-section flexible shafts. Perhaps you could revert to your study and analyze 2 scenarios with 2 different bend points.

BTW, you should be visiting Wishon Forum on regular basis, Mandrin - with your knowledge you could bring a flesh light to many subjects.

Cheers

Dariusz,

Thanks. I accept with pleasure your compliments, it compensates a bit for some other remarks made by our resident flag person.

I have used a homogeneous slender beam in my analysis and can assure you that the mathematics is already rather involved and even if there is always more to explore, before running, a bit of walking is perhaps not a bad exercise.

Varying the stiffness along the length of the shaft is adding another major complication. I have played around modeling the shaft also as multiple segments connected with appropriate dimensioned spring/dampers to model various “kick point’ into the shaft.

It is simply done just for the fun to see mathematics at work, not to design a new golf club. After all, golf club design is foremost subjective in which science plays a very minor role other than continuously coming up with new materials.

 

[Dariusz J.]

Mandrin, that's true what you said. If you have nothing against I'll post the link to your article on Wishon Forum - please be invited to pay a visit here.
BTW, Tom is also an avid physician so I think this article will be of his interest, too.
As I said, some of clubfitters have already started tinkering with a similar shaft phenomenon. However, there may be some problems with experiments - the supply of overally flexible shafts with a low torque is very very limited.
I don't know what torque value you would consider as low enough, but it's almost impossible to find a flexible shaft of less than 3.0 torque (Martix Ozik being the closest).
I bet, when this concept proves to be satisfactory (if ever), shaft manufacturers will find a way to produce such shaft types. Nanotechnology can be of help in this matter, I believe.

Thanks again for your article and comments.

Cheers

 

[mandrin]

whether or not it is possible to increase swing speed with a softer flex shaft, you have to figure in launch conditons or else all that extra speed won't necessarily make the ball go any further.

I can swing an A-flex shaft faster than my X but because of the face conditions at impact, it goes shorter.

Jim,

I am sure that if it was at all feasible to use eventually very flexible low torsion shafts that Brian in some corner of his matrix likely has a pattern to accommodate for such feat. If not he will surely arduously develop such pattern to stay ahead of the competition.

 

[mandrin]

Mandrin, that's true what you said. If you have nothing against I'll post the link to your article on Wishon Forum - please be invited to pay a visit here.
BTW, Tom is also an avid physician so I think this article will be of his interest, too.
As I said, some of clubfitters have already started tinkering with a similar shaft phenomenon. However, there may be some problems with experiments - the supply of overally flexible shafts with a low torque is very very limited.
I don't know what torque value you would consider as low enough, but it's almost impossible to find a flexible shaft of less than 3.0 torque (Martix Ozik being the closest).
I bet, when this concept proves to be satisfactory (if ever), shaft manufacturers will find a way to produce such shaft types. Nanotechnology can be of help in this matter, I believe.

Thanks again for your article and comments.

Cheers

Dariusz,

Go ahead, be my guest. I appreciate your courteous attitude so contrasting to the prevailing one where everything on the net is simply appropriated as one’s own property.

BTW, I noticed on the site EIOBA intelligent database that current shaft torque values seemingly go as low as 1.8 hence lower than your limit value of 3.0.

 

[nmgolfer]

My colleagues would be escorting you to the door Mandrin. That is if you were not already long gone after your recent "centrifugal force" fiasco. My colleagues all enjoyed a good laugh reading your post as did I.

There is no need to be rude Mandrin. You ungentlemanly behavior in the post below is yet another blatantly ploy to redirect attention from the subject at hand... a obvious flawed math model of a pendulum.

I don't get it? Its your problem if I don't understand you. That means you cannot communicate worth a damn. How about explaining yourself, using science and the english language in a manner that makes sense to mathematicians and scientists. Can you do that? FWIW I read and reread your web-page before I posted my reply because I could not believe you were making such ridiculous assertions.

Honestly question Mandrin... did you ever attend college? For that matter... finish high school? There is no wrong answer... Its OK if you didn't. Kinetic chains... http://www.google.com/search?client=safari&rls=en-us&q=kinetic+chain+physics&ie=UTF-8&oe=UTF-8
clearly thats just "sports lingo" not real science... well ok polymer physics and chemistry but Netwonian mechanics? You've got to be kidding!

nmgolfer, it is a pity but it isn’t even amusing anymore to see you again show your inaptitude to simply read a post or think about its content a bit coherently.

My first reaction was to quickly save your post to safeguard against another hasty deletion, due to obvious errors, it becoming a habit.

Your allusions to pendulums and conservation of energy are not pertinent. It is again obvious that you are stuck with high school physics and simply struggling to get maximum mileage out of it.

The simple truth is that you are clearly showing again being totally unaware of the dynamics of kinetic chains, specifically the interaction of linked segments.

Furthermore if you had really looked at my post instead of hastily posting nonsense you would have noticed the kinetic energy being equal at the bottom.

If colleagues read your post and the security guard promptly escorts you to the front door, there are certainly jobs available, using your speciality - “flagging”- to signal traffic, repairing roads.

 

[mandrin]

Surely the basic concept of this experiment is wrong?...
The clubhead doesn't simply "drop" during the golfswing, it is influenced by the hands, not just gravity.
PO is not a fixed position, as is stated, and the movement of PO in a real swing influences the velocity and behaviour of the head end..

Putmad, you are perhaps maddening good at putting but it is evident that this is not quite evident with regard to simply employing common sense.

There is obviously no attempt to simulate a golfer’s swing but rather to show that very flexible shafts allows one to use the potential energy in contrast to conventional shafts.

Also, even if the experiment were correct, the flexible shaft could not bend without input from the PO end.

Why? Explain.

The head would lead.

Why? Explain.

So all things being equal, both flexi and rigid assemblies, would reach the "bottom" at the same time (normal pendulum effect with no kicking of the shaft), so no increasee in acceleration with the flexi-shaft...

As nmgolfer you obviously lack basic knowledge about interaction of linked segments.


Nice try, but no cigar.

 

[Dariusz J.]

Dariusz,

Go ahead, be my guest. I appreciate your courteous attitude so contrasting to the prevailing one where everything on the net is simply appropriated as one’s own property.

BTW, I noticed on the site EIOBA intelligent database that current shaft torque values seemingly go as low as 1.8 hence lower than your limit value of 3.0.

Thank you.

As regards torques, yes, we can find torques lower than 2 but those values refer to stiff & X-stiff shafts; I was looking for the lowest possible torque of A-flex shaft.

Cheers

 

[bbftx]

22 mph, Nesbit, Grober

Mandrin,
I remember seeing you post this Whippy Club analysis on the Single Axis Swing Forum some years ago. Always a fun, interesting read.

Is the max swing speed in your model only about 22 mph? Rather slow, eh? I'd be interested in seeing your calculations for a more realistic club flex and swing speed.

To that end, have you read Nesbit's work on measurement and modeling of the golf swing?
He uses a 15 linked-segment mathematical model of a club in his attempts to correlate actual swing measurements to his more complex mathematical model. He has different opinions than you on the energy storage and release in the shaft. Through his model, and observing a variety of golfers, he concludes that "approximately half of the shaft stored strain energy is released by impact and converted to higher club head velocity."

Now, he does obtain his actual shaft damping characteristic used in his calcs by fixing shaft ends rigidly, like a cantilever. I believe he understands the limitations of this assumption, and this contributes to the inefficiency of energy storage/release in his "half the stored energy is converted" comment.

Also, Grober and others would disagree with your assertion that the natural frequency of a standard club is mismatched to time for a typical downswing. May I suggest you think about the "time" differently than using the typical "0.3 second time for a downswing" as equalling half of the cycle time? I would contend the shaft is still being loaded well into the downswing. It starts to unbend sometime around the "6-one-hundreths" position. (This, of course, then represents a one-quarter cycle time.) This gets you into the 4 to 5 cps frequency range of the typical golf shaft. Then, your modeling may give a different result for a shaft of typical stiffness and swing speed, better approximating real life. Let me know your thoughts

 

[jmessner]

whether or not it is possible to increase swing speed with a softer flex shaft, you have to figure in launch conditons or else all that extra speed won't necessarily make the ball go any further.

I can swing an A-flex shaft faster than my X but because of the face conditions at impact, it goes shorter.

Jim,

How much faster have you measured with an A-flex? I assume you're referring to extra launch angle caused by bend of the shaft, but what about accuracy spread - did you notice any decrease in directional repeatability? This has been one of the concerns with a significantly softer shaft than would normally be fitted.

Jay

 

[speedracer68]

Mandarin i am very interested in this discussion..but i have no desire to debate..the only thing i would like to know is how does this affect my equipment choices...

Are you saying if i use a stiff shaft and i switch to a regular or even a senior i will achieve more distance..thanks for any answers that you may have..=)

 

[Bronco Billy]

Mandarin i am very interested in this discussion..but i have no desire to debate..the only thing i would like to know is how does this affect my equipment choices...

Are you saying if i use a stiff shaft and i switch to a regular or even a senior i will achieve more distance..thanks for any answers that you may have..=)

Oh My God You called Him an Orange.....
http://www.hort.purdue.edu/newcrop/morton/mandarin_orange.html