'Pendulum' Stroke 'Sweet Spot' ?

ENGLISH! · May 6, 2013

Can someone please explain what bio-mechanical mechanism, if any, that would allow a 'sweet spot' of several inches of 'level' tip travel to occur in a true 'pendulum' stroke?

I don't see how it can exist with the elbow pinned in place & the forearm swinging like a pendulum unless the forearm gets longer & shorter & longer again as it swings, which we all know is not happening.

Per Bob Jewitt's chart, the tip moves down on an arc as the back hand swings up & the tip moves back up on an arc as the back hand swings down & then the tip moves down on an arc as the back hand swings up to the finish.

I just don't see how the tip can move in a linear straight line with the elbow 'pinned' at a point in space & the back hand swinging up, down & back up again. If the elbow is 'pinned' in space & the arm is swinginng as a pendulum rod taking the butt end of the cue with it then the tip on the other end of the cue must move in an arc of the opposite direction.

If it is the wrist action that would account for a bit of lengthening & shortening of the distance from the elbow to the connection point on the cue then it would take extreme coordination & timing to time that mechanism with a plan for it in mind.

I am looking for some logical biomechanical support for the supposed sweet spot of several inches of linear straight line tip travel in a true 'pendulum' stroke.

I just do not see how it is possible with the elbow 'pinned' in place.

Thanks in advance to anyone who can shed some true light on this subject.

allanpsand · May 6, 2013

It's not so much a matter that the tip follows in a straight line.

It is important that the tip/CB contact point be exactly where you intend it.

When working with students on how to achieve consistent draws, I emphasize that the student bring the tip up close to the CB, then verify that the forearm is exactly vertical to the stick.

Then, when the stroke is made, the tip hits at the intended point on the CB.

Before or after the tip/CB contact, it doesn't matter what the stick does. All you want to make sure of is the actual contact.

(Disclaimer: this assumes no other body parts are moving until after the tip/CB hit.)

ENGLISH! · May 6, 2013

allanpsand said:
It's not so much a matter that the tip follows in a straight line.

It is important that the tip/CB contact point be exactly where you intend it.

When working with students on how to achieve consistent draws, I emphasize that the student bring the tip up close to the CB, then verify that the forearm is exactly vertical to the stick.

Then, when the stroke is made, the tip hits at the intended point on the CB.

Before or after the tip/CB contact, it doesn't matter what the stick does. All you want to make sure of is the actual contact.

(Disclaimer: this assumes no other body parts are moving until after the tip/CB hit.)

Thanks for the reply.

I am not a believer that what happens before or after contact makes no difference as those two things are cause & effect related. That being said, I understand that the only influence we have on the cue ball is the 1/1000 to 2/1000 of a second contact that we make with the tip on the end of a straight line linear stick.

The point you made is my point. Since the tip is arcing all over the place in a true 'pendulum' stroke, a true 'pendulum' stroke takes a perfect set up to hit the ball any where near the time that the tip is changing from an arc in one direction to an arc in another direction. How can one expect to hit the cue ball on the spot of the vertical axis one intends when the tip is arcing down, up, & back down again. There is virtually no room for errror as opposed to a stroke that moves the tip straight back, into & through the contact.

From your response, I take it that you agree that there is no 'sweet spot' or zone where the tip is moving in a straight linear line for several inches in a true 'pendulum stroke.

If not, can you explain what biomechanical mechanism would allow or make that happen.

Thanks again,

BilliardsAbout · May 6, 2013

The sweet spot or extended flat spot near the bottom of a "pendulum stroke" is real, but very, very short and not several inches in length.

One of several issues with comparing a pendulum arc to a pool stroke is the white ball. Imagine the pendulum of a grandfather clock striking a cue ball near the bottom of its arc. It won't go "straight down the aim line parallel to the cloth" a long distance, but a short distance, before swinging upward again...

ENGLISH! · May 6, 2013

BilliardsAbout said:
The sweet spot or extended flat spot near the bottom of a "pendulum stroke" is real, but very, very short and not several inches in length.

One of several issues with comparing a pendulum arc to a pool stroke is the white ball. Imagine the pendulum of a grandfather clock striking a cue ball near the bottom of its arc. It won't go "straight down the aim line parallel to the cloth" a long distance, but a short distance, before swinging upward again...

Mr. Sherman,

Thanks for your reply.

Keep in mind that I am referring to the travel of the tip while you seem to be referring to movement of the hand at the end of the arm which would be the butt end of the cue. When the arm swings back & up the tip arcs downward. Then when the arm swings down the tip arcs upward. Then when the arm swings up to the finish the tip arcs downward again.

I would venture to say that there is virtually no flat spot as the tip changes from arcing up to arcing down in an instant & happens in a miniscue amount of distance in the direction the cue is moving. To time when that actually happens seems to be nearly impossible for all practical purposes AND would require a perfect set up for the tip to contact the cue ball at the instant it is changing from an upward acr to a downward arc.

If one's forearm is not exactly perpendicular to the cue, not the table, then one would be hitting with a tip that is arcing either upward or downward depending on what side of perendicular to the cue the arm is at contact.

When swinging a baseball bat it is better to have as long of a flat level travel of the bat as possibly as it is in golf as well. There are biomechanics of a rotary nature that help to accomplish this.

I see no such biomechanical mechanisms to allow such in a true pendulum stroke.

Are you aware of any that would accomplish a straight tip path of travel in a true pendulum stroke?

Is anyone aware of any biomechanical mechanism that would get the tip moving in a straight linear line with a true 'pendulum' stroke?

Thanks again.

Mark Avlon · May 6, 2013

It's a safe bet that everyone here would agree that a pendulum stroke doesn't result in perfectly straight movement over some distance. That doesn't invalidate the effectiveness, and consistency of a pendulum stroke, nor the ease that it can be learned and mastered.

ENGLISH! said:
If it is the wrist action that would account for a bit of lengthening & shortening of the distance from the elbow to the connection point on the cue then it would take extreme coordination & timing to time that mechanism with a plan for it in mind

The need for extreme coordination and timing is critical to a piston stroke, and much more difficult to master. This doesn't invalidate the effectiveness of this stroke either.

People are not precision machines and their strokes will have imperfections. Eliminating them is not a realistic goal. Minimizing them is.

Can you honestly say that a piston stroke is as easy or easier to learn and master as a pendulum stroke for the general population of pool players? I think few would agree that it is. Which stroke would you suggest that a typical beginning or intermediate player learn when they are trying to get their mechanics in order, and why? I recommend the pendulum stroke as the student can dramatically improve the consistency and accuracy of their stroke very quickly and easily. I have no opposition to anyone learning a piston stroke if they so choose.

ENGLISH! · May 6, 2013

Mark Avlon said:
It's a safe bet that everyone here would agree that a pendulum stroke doesn't result in perfectly straight movement over some distance. That doesn't invalidate the effectiveness, and consistency of a pendulum stroke, nor the ease that it can be learned and mastered.

The need for extreme coordination and timing is critical to a piston stroke, and much more difficult to master. This doesn't invalidate the effectiveness of this stroke either.

People are not precision machines and their strokes will have imperfections. Eliminating them is not a realistic goal. Minimizing them is.

Can you honestly say that a piston stroke is as easy or easier to learn and master as a pendulum stroke for the general population of pool players? I think few would agree that it is. Which stroke would you suggest that a typical beginning or intermediate player learn when they are trying to get their mechanics in order, and why? I recommend the pendulum stroke as the student can dramatically improve the consistency and accuracy of their stroke very quickly and easily. I have no opposition to anyone learning a piston stroke if they so choose.

Thanks for your input.

I think the notion that a piston type stroke takes more coordination & timing can be a bit misleading. I never give any thought to coordinating or timing anything in my piston like stroke. I simply move the stick & the tip on the end of the straight stick straight back & forth. The natural biomachanics simply do what they do to accomplish that task. There is no conscious thought or effort to coordinate or time anything.

A piston type stroke might be more difficult to break down exactly what happens & when & then teach that as compared to a 'pendulum' stroke. But what is easier to teach is not my concern.

I am not asking what is easy to teach. As Slasher has suggested & I agree, if one is left to their own 'devices' without any outside input to interfere with that process most people would gravitate naturally to the piston type stroke as so many snooker players have where accuracy is so important & as I did as a 13 year old 'child'.

Why would one want the tip arcing down, up & down again when trying to precisely hit a point on the cue ball when one could simply move the cue & the tip in a straight line back & forth movement?

Like you, I also have no opposition to anyone learning what ever stroke one wants to learn. I am merely pointing out the differences in the path that the tip takes & suggesting that a straight line is perhaps a better means to use when trying to precisely hit a point on a cue ball with the tip of a straight line stick.

Personally, I see no advantage to a pendulum stroke other than the fact that it may be easier to teach. In fact, I see the need for a perfect setup for a pendulum stroke to work as intended as a disadvantage, especially when playing on larger tables.

If there is a mechanism that would get the tip moving straight in a true pendulum stroke then I might be convinced that it might be as good a stroke as a straight line piston type stroke. As of now I do not see it as such & even then it would seem that it would still reguire a near perfect set up to work as intended.

I take it from you response that you know of no such mechanism. Perhaps randyG will chime in as I believe it was he that refered to the several inches of level tip travel 'sweet spot' in another thread. Perhaps I am wrong & he was referring to something else. In either case I just don't see it, especially not with the 'craddle' grip.

If no one can explain it to me then I guess that that 'sweet spot' simply does not exist. If that is the case then I would rather see people learn a piston like stroke instead.

Naturallly these are all just my opinions & I am not certified as an instructor.

Thanks again for your input.

Mark Avlon · May 6, 2013

ENGLISH! said:
But what is easier to teach is not my concern.

Nor mine. My concern is what's easiest for my students to learn and master while providing excellent results, so that they can meet their goals.

ENGLISH! · May 6, 2013

Mark Avlon said:
Nor mine. My concern is what's easiest for my students to learn and master while providing excellent results, so that they can meet their goals.

That's interesting.

In golf, it's easier to learn how to hit a fade & one can have excellent results playing that way. Yet, almost every golfer wants to learn how to hit a draw, which seems to be a bit more difficult to learn & thus a bit more difficult to teach.

It was easy for my son to learn how to hit a fade in golf. I taught him to hit a draw as well. Today he hits both at will & he knows what one is 'better'.

I wanted what was best for my son, not just what was easiest for him to learn.

The easiest things are usually not the best things. They are just easier.

I guess it really does depend on one's goals & what one wants out of their stroke & game. I guess it really is different strokes for different folks. If one is happy with a pendulum stroke, so be it.

I just think everyone should know all of their options & make their own objective determinations. I don't buy what the salesman wants to sell me. I buy what I want to buy when I have enough information to make an intelligent objective decision based on all of the objective information available to me & not just what the salesman tells me.

I just think everyone should know that there are other options & make their own objective decisions as to what stroke they want to learn based on their own objective analysis.

I simply prefer to utilize a straight traveling cue tip rather than one that is moving in three(3) arcs.

I wish you & your students all the best of success.

Neil · May 7, 2013

ENGLISH! said:
Thanks for your input.

I think the notion that a piston type stroke takes more coordination & timing can be a bit misleading. I never give any thought to coordinating or timing anything in my piston like stroke. I simply move the stick & the tip on the end of the straight stick straight back & forth. The natural biomachanics simply do what they do to accomplish that task. There is no conscious thought or effort to coordinate or time anything.

A piston type stroke might be more difficult to break down exactly what happens & when & then teach that as compared to a 'pendulum' stroke. But what is easier to teach is not my concern.

I am not asking what is easy to teach. As Slasher has suggested & I agree, if one is left to their own 'devices' without any outside input to interfere with that process most people would gravitate naturally to the piston type stroke as so many snooker players have where accuracy is so important & as I did as a 13 year old 'child'.

Why would one want the tip arcing down, up & down again when trying to precisely hit a point on the cue ball when one could simply move the cue & the tip in a straight line back & forth movement?

Like you, I also have no opposition to anyone learning what ever stroke one wants to learn. I am merely pointing out the differences in the path that the tip takes & suggesting that a straight line is perhaps a better means to use when trying to precisely hit a point on a cue ball with the tip of a straight line stick.

Personally, I see no advantage to a pendulum stroke other than the fact that it may be easier to teach. In fact, I see the need for a perfect setup for a pendulum stroke to work as intended as a disadvantage, especially when playing on larger tables.

If there is a mechanism that would get the tip moving straight in a true pendulum stroke then I might be convinced that it might be as good a stroke as a straight line piston type stroke. As of now I do not see it as such & even then it would seem that it would still reguire a near perfect set up to work as intended.

I take it from you response that you know of no such mechanism. Perhaps randyG will chime in as I believe it was he that refered to the several inches of level tip travel 'sweet spot' in another thread. Perhaps I am wrong & he was referring to something else. In either case I just don't see it, especially not with the 'craddle' grip.

If no one can explain it to me then I guess that that 'sweet spot' simply does not exist. If that is the case then I would rather see people learn a piston like stroke instead.

Naturallly these are all just my opinions & I am not certified as an instructor.

Thanks again for your input.

English, you try and make it sound like there is some great big arc to the pendulum swing. In the past you have been given charts and videos that give the answers you seek. Yet, you still ask them?? Here's another group of videos where the guy uses a pretty good pendulum stroke, do you see and big arc in his stroke? Have you ever even tried the pendulum stroke? If you had, you would know that the questions you ask are way out in left field. http://forums.azbilliards.com/showthread.php?t=319281 Here's another one- https://www.youtube.com/watch?v=d66YXa8QENI&feature=youtu.be

BilliardsAbout · May 7, 2013

I'm thinking of the tip also. The tip has to, on a perfectly timed pendulum stroke, straighten for a bit (straight AND down for most good players for most strokes) as it impacts the cue ball and beyond, but this length can be measured in tiny fractions of an inch and not several inches.

There is another thread nearby advocating smaller follow through or follow through about equal to backstroke length--this "several inches" straight through the ball is unlikely for most strokes...

Neil · May 7, 2013

BilliardsAbout said:
I'm thinking of the tip also. The tip has to, on a perfectly timed pendulum stroke, straighten for a bit (straight AND down for most good players for most strokes) as it impacts the cue ball and beyond, but this length can be measured in tiny fractions of an inch and not several inches.

There is another thread nearby advocating smaller follow through or follow through about equal to backstroke length--this "several inches" straight through the ball is unlikely for most strokes...

The "arc" is so small that the cue is level for several inches.

ENGLISH! · May 7, 2013

Neil said:
English, you try and make it sound like there is some great big arc to the pendulum swing. In the past you have been given charts and videos that give the answers you seek. Yet, you still ask them?? Here's another group of videos where the guy uses a pretty good pendulum stroke, do you see and big arc in his stroke? Have you ever even tried the pendulum stroke? If you had, you would know that the questions you ask are way out in left field. http://forums.azbilliards.com/showthread.php?t=319281 Here's another one- https://www.youtube.com/watch?v=d66YXa8QENI&feature=youtu.be

Neil,

I am not trying to make it sound like there is a great big huge arc like in The Pit & the Pendulum. But there are three(3) small arcs in a true pendulum. I believe randyG said that the tip moves 'level' for several inches. I am merely asking for some explanation of what biomechanics would allow or make that happen as I do not see it.

I see in your next post that you agree with this. Can you explain just how that is possible? But before you do, do you agree that missing the cue ball by say 2 or 3 millimeters on the vertical axis can cause problems with consistant control of the cue ball? Many seem to want to say that differences are insignificant for other aspects too. I am not of that line of thinking. I feel any difference is significant, especially when we are dealing with the three(3) millimeters of a tip contact patch & the infinitely small contact between the cue ball & object balls.

Let me say that the gentleman in the first video shot rather well. But to answer your question, yes an arc of the tip can be seen on certain shots where he was not merely popping the cue ball with a jab stroke. The second video was too far away so I did not even watch it.

I have never said that one could not play well with a pendulum stroke. But I see potential problems wth it & feel that a straight line pistion type stroke is better for those reasons. It is often said that a piston type stroke is much more difficult to learn & maintain consistency due to the higher level of coordination & timing needed. I do not agree with that line of thinking either. I have never given any thought to coordinating or timing anything. The natural biomechanics to move the cue & the tip in a straight line simply happen on their own. I only focus on moving the cue straight back & straight forward, simple, very simple.

I am not looking to get into a drag out to divert attention from the question that I have asked. I am merely looking for an explanation as to how the several inches of 'sweet spot' level tip travel happens. What biomechanical mechanism allows or makes that happen? If it can be legitimatley explained & not just glossed over as a shallow arc is nearly straight or the three(3) arcs cancel each other out so the net effect is a straight line. Then perhaps my opinion of the pendulum stroke will change.

Feathers were put on an arrow to make it go straight & not wobble all over the place. Straight is more accurate when trying to hit a very small target. JMHO.

Please enlighten me if I am wrong.

Regards,

randyg · May 7, 2013

ENGLISH! said:
Neil,

I am not trying to make it sound like there is a great big huge arc like in The Pit & the Pendulum. But there are three(3) small arcs in a true pendulum. I believe randyG said that the tip moves 'level' for several inches. I am merely asking for some explanation of what biomechanics would allow or make that happen as I do not see it.

I see in your next post that you agree with this. Can you explain just how that is possible? But before you do, do you agree that missing the cue ball by say 2 or 3 milimeters on the vertical axis can cause problems with consistant control of the cue ball? Many seem to want to say that differences are insignificant for other aspects too. I am not of that line of thinking. I feel any difference is significant, especially when we are dealing with the three(3) millimeters of a tip contact patch & the infinitely small contact between the cue ball & object balls.

Let me say that the gentleman in the first video shot rather well. But to answer your question, yes an arc of the tip can be seen on certain shots where he was not merely popping the cue ball with a jab stroke. The second video was too far away so I did not even watch it.

I have never said that one could not play well with a pendulum stroke. But I see potential problems wth it & feel that a straight line pistion type stroke is better for those reasons. It is often said that a piston type stroke is much more difficult to learn & maintain consistency due to the higher level of coordination & timing needed. I do not agree with that line of thinking either. I have never given any thought to coordinating or timing anything. The natural biomechanics to move the cue & the tip in a straight line simply happen on their own. I only focus on moving the cue straight back & straight forward, simple, very simple.

I am not looking to get into a drag out to divert attention from the question that I have asked. I am merely looking for an explanation as to how the several inches of 'sweet spot' level tip travel happens. What biomechanical mechanism allows or makes that happen? If it can be legitimatley explained & not just glossed over as a shallow arc is nearly straight or the three(3) arcs cancel each other out so the net effect is a straight line. Then perhaps my opinion of the pendulum stroke will change.

Feathers were put on an arrow to make it go straight & not wobble all over the place. Straight is more accurate when trying to hit a very small target. JMHO.

Please enlighten me if I am wrong.

Regards,

Several: "two or more"!

Neil · May 7, 2013

ENGLISH! said:
Neil,

I am not trying to make it sound like there is a great big huge arc like in The Pit & the Pendulum. But there are three(3) small arcs in a true pendulum. I believe randyG said that the tip moves 'level' for several inches. I am merely asking for some explanation of what biomechanics would allow or make that happen as I do not see it.

I see in your next post that you agree with this. Can you explain just how that is possible? But before you do, do you agree that missing the cue ball by say 2 or 3 milimeters on the vertical axis can cause problems with consistant control of the cue ball? Many seem to want to say that differences are insignificant for other aspects too. I am not of that line of thinking. I feel any difference is significant, especially when we are dealing with the three(3) millimeters of a tip contact patch & the infinitely small contact between the cue ball & object balls.
Of course 3 mil. is significant. That's why trying to go level all the way is usually not a good way to go. It's very difficult to make the cue actually stay level, as is attested to by the thousands of amateurs that can't hit where they are trying to hit on the cb.

Let me say that the gentleman in the first video shot rather well. But to answer your question, yes an arc of the tip can be seen on certain shots where he was not merely popping the cue ball with a jab stroke. The second video was too far away so I did not even watch it.

I have never said that one could not play well with a pendulum stroke. But I see potential problems wth it & feel that a straight line pistion type stroke is better for those reasons. It is often said that a piston type stroke is much more difficult to learn & maintain consistency due to the higher level of coordination & timing needed. I do not agree with that line of thinking either. I have never given any thought to coordinating or timing anything. The natural biomechanics to move the cue & the tip in a straight line simply happen on their own. I only focus on moving the cue straight back & straight forward, simple, very simple.
Yet, how often can you precisely hit the cb where you want to?

I am not looking to get into a drag out to divert attention from the question that I have asked. I am merely looking for an explanation as to how the several inches of 'sweet spot' level tip travel happens. What biomechanical mechanism allows or makes that happen? If it can be legitimatley explained & not just glossed over as a shallow arc is nearly straight or the three(3) arcs cancel each other out so the net effect is a straight line. Then perhaps my opinion of the pendulum stroke will change.
The arc is so small in reality that it is level at contact for several inches.

Feathers were put on an arrow to make it go straight & not wobble all over the place. Straight is more accurate when trying to hit a very small target. JMHO.
Then why do so many have so much trouble with it?

Please enlighten me if I am wrong.

Regards,

Actually, as Randy pointed out, "several" means more than two. I should have said "a couple of inches", instead of "several".

ENGLISH! · May 7, 2013

randyg said:
Several: "two or more"!

Thanks for the definition.

Two inches would be 'a couple' of inches.

More than two(2) would be 'several'.

Can you please explain what biomechanics would allow or make the cue tip travel straight for 'two or more inches' in a true pendulum stroke?

I know you seem to be a man of few words, but the 'definition of 'several' is not an explanation of how it happens, even if it is ony two(2) inches.

I know how to expand the 'flat' 'sweet spot' in a rotary baseball & golf swing & I know how it occurs in a piston stroke but I don't even 'see' how one is possible in a true pendulum stroke, especially with a 'craddle' grip.

Would you please be so kind as to enlighten me. It was your comment that intrigued me.

Neil seems to agree with you but as of yet no one has been forth coming with an explanation of how it occurs.

I brought the question up weeks ago in the other thread but there was no explanation so I started this thead & while there has been responses by now three(3) instructors & Neil, still no one has offered an explanation of how it can occur. Actually Mr. Avlon, an Advanced PBIA Instructor, seems to think that straight tip travel does not exist in a true pendulum stroke. He seems to doubt that anyone would suggest that it exists. Mr. Sherman seems to think that it is miniscue in amount & certainly not several inches.

I have looked at Bob Jewitt's tip travel charts & I just don't see it.

If the tip actually moves in a straight line for two(2) inches, I & I would think others would like to know how that happens when the forearm is swinging on an arc like a pendulum from a fixed elbow position while sitting in a 'craddle' grip.

Your statement intrigued me & I have an inquiring mind. Inguiring minds want to know.

Would you please enlighten me?

Regards & thanks in advance should you choose to be forth coming with an explanation.

randyg · May 7, 2013

ENGLISH! said:
Thanks for the definition.

Two inches would be 'a couple' of inches.

More than two(2) would be 'several'.

Can you please explain what biomechanics would allow or make the cue tip travel straight for 'two or more inches' in a true pendulum stroke?

I know you seem to be a man of few words, but the 'definition of 'several' is not an explanation of how it happens, even if it is ony two(2) inches.

I know how to expand the 'flat' 'sweet spot' in a rotary baseball & golf swing & I know how it occurs in a piston stroke but I don't even 'see' how one is possible in a true pendulum stroke, especially with a 'craddle' grip.

Would you please be so kind as to enlighten me. It was your comment that intrigued me.

Neil seems to agree with you but as of yet no one has been forth coming with an explanation of how it occurs.

I brought the question up weeks ago in the other thread but there was no explanation so I started this thead & while there has been responses by now three(3) instructors & Neil, still no one has offered an explanation of how it can occur. Actually Mr. Avlon, an Advanced PBIA Instructor, seems to think that straight tip travel does not exist in a true pendulum stroke. He seems to doubt that anyone would suggest that it exists. Mr. Sherman seems to think that it is miniscue in amount & certainly not several inches.

I have looked at Bob Jewitt's tip travel charts & I just don't see it.

If the tip actually moves in a straight line for two(2) inches, I & I would think others would like to know how that happens when the forearm is swinging on an arc like a pendulum from a fixed elbow position while sitting in a 'craddle' grip.

Your statement intrigued me & I have an inquiring mind. Inguiring minds want to know.

Would you please enlighten me?

Regards & thanks in advance should you choose to be forth coming with an explanation.

The term "pendulum stroke" is very misunderstood. For the most of us it is a mini pendulum with a leveling out at the bottom. Looks like a small arc rather than pendulum.

randyg

ENGLISH! · May 7, 2013

randyg said:
The term "pendulum stroke" is very misunderstood. For the most of us it is a mini pendulum with a leveling out at the bottom. Looks like a small arc rather than pendulum.

randyg

It is becoming more & more apparent to me that you are a man of very few words.

A mini pendulum would refer to the length of the pendulum rod or the length of the radius. That would be different for each individual depending on the length of their forearm.

An arc is the shape of the motion at the end of the pendulum at the end of the radius rod.

The end of the the radius moves in a an arc curve which is a part of a circle. A tangent line that is perpendicular to the motion does exist, but no two tangent lines will be in line with each other, not even one to the next one.

There is no straight line travel at the end of a pendulum or a radius. The movement is along the curve of the arc.

You, Neil & others have suggested that the tip travels in a straight lone for a coulple of inches.

On what do you base that assertion?

Bob Jewitt's tip travel chart & my physics education does not support that assertion.

That is why I am asking for what biomechanical mechanism would allow or make the tip travel in a straight line for a couple of inches.

Do you have a logical explanation for your assertion?

An arc is the curved travel that occurs at the end of a radius like in a pendulum. There is no straight line travel at the end of a radius like in a pendulum. The circular line of movement would be traveling 'level' & perpendicular to the pull of gravity for one & only one point unless the radius center, (the elbow) moves. If the raidus center is stationary the movement at the end of the radius (the forearm) can only move in a circular type arc.

Something has to change to allow for any straight line movement.

I am merely asking what biomechanical movement or mechanism in a true 'pendulum' stroke would allow or make a straight line movement of the tip happen.

If it actually does move straight for a couple of inches, I would think that the answer would be simple.

That does not seem to be the case as no answer has been provided.

Again would you please enlighten me. What if anything am I failing to see &/or consider?

Regards,

randyg · May 7, 2013

OK, I'm going to take just one guess.

We are humans not graphs!!!!!!!!!

randyg

ENGLISH! · May 7, 2013

randyg said:
OK, I'm going to take just one guess.

We are humans not graphs!!!!!!!!!

randyg

Sir,

I agree. We are not graphs. We are biological entities with certain biomechanical capabilities. As far as I know we are still confined by the sciences & can not overcome them merely because we want or wish something to be a particular way.

I guess the only way I can logically take this response of yours is that you have nothing to support your assertion that the the tip travels straight for two or more inches, in what you called a 'sweet spot'.

If my guess is incorrect I would welcome a claraification.

Regards & Best Wishes,

'Pendulum' Stroke 'Sweet Spot' ?

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