Practical demonstration of cue tip path with a Pendulum stroke.

Neil said:
In the video I had provided, my wrist moves very, very little. I also explained in detail to him what causes the cue to stay level. He just chooses to ignore it, and now states that he has never been given that explanation. He will just keep picking at little tiny slivers that have everyone shaking their heads in disbelief instead of admitting to being wrong.
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From what I've seen in the main forum threads, a boatload of effort has gone into trying to explain things to a single person who already has it in their head that they're right. It's pretty hard to change somebody that's had tunnel vision for 47 years.

I think you should just start telling him that he's right any time he pipes up and go back to whoever you were talking to before. Otherwise, you'll just be feeding into his argument, because you know it'll be coming.
 
By the way, this line of questioning, i.e., whether tip motion, when using a pendulum stroke, can ever be perfectly linear (which, of course, it can't), seems to be allowing for a presupposition that a person using a 'piston' stroke can somehow deliver the cue tip in straight line motion.

I would assume the contrary: The simultaneous, coordinated movement of both the upper arm and the forearm to achieve perfectly linear motion of the cue tip is very difficult. That it might look linear, is simply a consequence of the same condition that allows the pendulum stroke to appear to move the cue tip in almost linear travel within that small range in question, to wit: Stroke errors at the tip are minimized by the ~5:1 ratio of the cue length behind the bridge to the length in front of the bridge.
 
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oldschool1478 said:
Great pendulum stroke simulator Greg!
I also wondered about the results if the cue was at 15 deg. to the slate.
In the true spirit of science/engineering, I used a parametric cad program to verify your findings.
As the screen capture shows, the variation at the cue tip in the vertical plane takes on a slight "s" curve in shape,
and in my example deviates no more than 0.075" and in the last 3" there is no more than 0.016" deviation.
In my opinion, that's pretty damn straight!
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oldschool,

Thank you for your efforts.

Please me tell me if I am reading that correctly?

The green line is a straight line.

The purple line represents the path of the tip.

When the tip is just in front of the bridge it is below the 'level' of the straight line.

As it progresses toward the ball it travels along the path of an arc that rises & then transitions & travels along the path of a different arc moving down to the ball.

Have I describe that correctly?

And yes, that is some rather small deviations.

Edit: I don't know why the graph did not copy?
 
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swest said:
By the way, this line of questioning, i.e., whether tip motion, when using a pendulum stroke, can ever be perfectly linear (which, of course, it can't), seems to be allowing for a presupposition that a person using a 'piston' stroke can somehow deliver the cue tip in straight line motion.

I would assume the contrary: The simultaneous, coordinated movement of both the upper arm and the forearm to achieve perfectly linear motion of the cue tip is very difficult. That it might look linear, is simply a consequence of the same condition that allows the pendulum stroke to appear to move the cue tip in almost linear travel within that small range in question, to wit: Stroke errors at the tip are minimized by the ~5:1 ratio of the cue length behind the bridge to the length in front of the bridge.
Click to expand...

Good post, swest. The large ratio of cue in back of the bridge vs. in front of the bridge helps "flatten out" "any perceived" rise and fall of the tip. Most of that rise and fall is seen at the butt, not at the tip.

And I 100% agree -- the notion that a piston stroke somehow makes "a more straight-traveling cue vs. the rise and fall of a pendulum stroke" is a big stretch considering the increased Rube Goldberg-esque coordination that needs to occur between the shoulder and the elbow. Consider that Rick has already committed to telling us that: 1.) he doesn't "chin" the cue (which would be the self-troubleshooting technique to use to determine if your cue is really travelling as straight as you think -- if your cue rises and falls, you'd certainly feel it push and pull away from your chin), and 2.) as evidenced by his own signature and past posting history, he doesn't subscribe to the notion of instructors nor the teaching techniques they use -- e.g. filming a student's stroke and showing where the hooks/crooks and inconsistencies appear. No, you're supposed to "be responsible for your own game and not let anyone intercept what comes naturally to you."

"What I think my stroke is doing is indeed what it is doing." Yep, we all believe that, until we see video evidence to the contrary.

-Sean
 
English.
The green line is the cue at address.
When the tip is pulled back 10" it is exactly on the start (bridge pivot) of the S curve.
When the stroke swings forward it immediately starts downward to it's lowest point (0.075" below the center-line of the cue at address. It then swings upward crossing that line to it's highest point (0.015), and then back down to contact at the equator of the cue ball.

This is plotted in a cad program that allows me to fix the end points of certain lines,
and pivot on other's, dynamically.

Obviously, no human can swing a cue in a perfect pendulum fashion, or piston like either for that matter. With fewer moving parts, the pendulum will most likely produce the most consistent results, for us humans.
 
Actually, we have two winners:

sfleinen said:
the notion that a piston stroke somehow makes "a more straight-traveling cue vs. the rise and fall of a pendulum stroke" is a big stretch considering the increased Rube Goldberg-esque coordination that needs to occur between the shoulder and the elbow.
Click to expand...
 
oldschool1478 said:
English.
The green line is the cue at address.
When the tip is pulled back 10" it is exactly on the start (bridge pivot) of the S curve.
When the stroke swings forward it immediately starts downward to it's lowest point (0.075" below the center-line of the cue at address. It then swings upward crossing that line to it's highest point (0.015), and then back down to contact at the equator of the cue ball.

This is plotted in a cad program that allows me to fix the end points of certain lines,
and pivot on other's, dynamically.

Obviously, no human can swing a cue in a perfect pendulum fashion, or piston like either for that matter. With fewer moving parts, the pendulum will most likely produce the most consistent results, for us humans.
Click to expand...

oldschool,

Please forgive me.

But are you saying, that the tip travels on a series of arcs for a fixed elbow pendulum stroke?

Thanks,
Rick
 
But are you saying, that the tip travels on a series of arcs for a fixed elbow pendulum stroke?
Thanks,
Rick

Actually an "S" shaped spline. The drawing shows it very clearly.
My point was to show how nearly straight it actually is. :wink:
 
oldschool1478 said:
But are you saying, that the tip travels on a series of arcs for a fixed elbow pendulum stroke?
Thanks,
Rick

Actually an "S" shaped spline. The drawing shows it very clearly.
My point was to show how nearly straight it actually is. :wink:
Click to expand...

Thank you again.

May I quote you?:wink:

I understand your point about 'nearly straight'.

I think very much could have been avoided if randyG would have said, 'nearly straight' or would have simply clarified himself to have meant to say 'nearly straight'.

Now since you are being so honestly kind, may I ask you another question?

In your opinion, is there a section along that 'nearly straight' path that you would call or term as a 'sweet spot' in relation to being 'straight'?

I thank you again for your kindness & honesty.

And...I will restate again that I understand your point about being 'nearly straight'.

Regards & Best Wishes,
Rick
 
ENGLISH! said:
Thank you again.

May I quote you?:wink:

I understand your point about 'nearly straight'.

I think very much could have been avoided if randyG would have said, 'nearly straight' or would have simply clarified himself to have meant to say 'nearly straight'.

Now since you are being so honestly kind, may I ask you another question?

In your opinion, is there a section along that 'nearly straight' path that you would call or term as a 'sweet spot' in relation to being 'straight'?

I thank you again for your kindness & honesty.

And...I will restate again that I understand your point about being 'nearly straight'.

Regards & Best Wishes,
Rick
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Nice....now we are down to picking mites off hair follicles. WAYYYY past picking hairs.This would actually be hilarious if it wasn't so sad. :( Yet, for some reason, I can't seem to stop laughing.:o

edit: I have to ask this....what are the time frames for how long it takes Rick to use that quote he asked permission to use for ammo to prove that the stroke is not straight after all?? An hour, a day, a week?
 
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In my opinion, there is a section along that 'nearly straight' path that I would call or term as a 'sweet spot' in relation to being 'straight.'
That would be between the crossover point and about 1/8" past CB contact, where deviation is no more than 0.015". If that is not straight enough for you, you are taking 'anal' to a whole new level, and you may quote me on that if you include this sentence.
 
Neil said:
Nice....now we are down to picking mites off hair follicles. WAYYYY past picking hairs.This would actually be hilarious if it wasn't so sad. :( Yet, for some reason, I can't seem to stop laughing.:o

edit: I have to ask this....what are the time frames for how long it takes Rick to use that quote he asked permission to use for ammo to prove that the stroke is not straight after all?? An hour, a day, a week?
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Now I'm curious as to how "straight" or "nearly straight" or "almost straight" or "straight enough" his "piston" stroke is that he's finely tuned over the course of 47 years. I found it funny he tried to tell somebody that they were avoiding his question when he still won't say what makes him worth taking seriously, other than holding a stick for 47 years. It certainly isn't an engineering degree, I'm sure of that.. or at least, "nearly sure".
 
The money shot in this thread:

oldschool1478 said:
In my opinion, there is a section along that 'nearly straight' path that I would call or term as a 'sweet spot' in relation to being 'straight.'
That would be between the crossover point and about 1/8" past CB contact, where deviation is no more than 0.015". If that is not straight enough for you, you are taking 'anal' to a whole new level, and you may quote me on that if you include this sentence.
Click to expand...

ROFLMAO
 
Banks said:
Now I'm curious as to how "straight" or "nearly straight" or "almost straight" or "straight enough" his "piston" stroke is that he's finely tuned over the course of 47 years. I found it funny he tried to tell somebody that they were avoiding his question when he still won't say what makes him worth taking seriously, other than holding a stick for 47 years. It certainly isn't an engineering degree, I'm sure of that.. or at least, "nearly sure".
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Well, according to him, he has never even looked at his stroke, or given it a seconds thought until very recently. So, the answer is, he has no idea.
 
oldschool1478 said:
In my opinion, there is a section along that 'nearly straight' path that I would call or term as a 'sweet spot' in relation to being 'straight.'
That would be between the crossover point and about 1/8" past CB contact, where deviation is no more than 0.015". If that is not straight enough for you, you are taking 'anal' to a whole new level, and you may quote me on that if you include this sentence.
Click to expand...

I just wanted your honest opinion.

Thanks for the honesty.
 
oldschool1478 said:
In my opinion, there is a section along that 'nearly straight' path that I would call or term as a 'sweet spot' in relation to being 'straight.'
That would be between the crossover point and about 1/8" past CB contact, where deviation is no more than 0.015". If that is not straight enough for you, you are taking 'anal' to a whole new level, and you may quote me on that if you include this sentence.
Click to expand...

en.wikipedia.org/wiki/Hair‎
The diameter of human hair varies from 17 to 180 micrometers (0.00067 to 0.0071 in).

Just to put things in a little perspective, we are talking about the width of two hairs.
 
ENGLISH! said:
Also, since the 'cue' is a piece of square wood, I am not so sure that it is a straight piece of wood.
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Who knows? It may be straighter than the cue you are using. I've played in seedy bars my whole life. If I ever picked up a house cue with less than 1/16" of a curve along its length I'd think it was one of Tramp's "Miracle Cues". We're talking about 15 thou deviation in tip travel in a pure pendulum stroke for Christ's sake! Get real, will you?

You know, I'd put you back on ignore but it's just way too much fun watching you unravel. Soon you will be banned again, and we will get, what, a one year vacay from you this time? Can't wait until I can come back and post in peace once more.

Oh, by the way, have a blessed day.:rolleyes:
 
Folks:

This ain't fair. I'm watching "Top Gear: in Australia" and laughing my butt off at those nutcases (love 'em!), and then when commercial break comes on, I redirect my attention here, and continuing to laugh my butt off with no break.

Will you guys give me a breather break, for christmas sake? :p :D

-Sean
 
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