$100 Spin Challenge

[Patrick Johnson]

With automatic adjustments available like BHE, [low squirt] is NOT more accurate.

BHE is not an automatic adjustment. It's an approximation that leaves final adjustment up to the player. Low squirt shafts reduce the amount of adjustment necessary, with or without BHE.

pj
chgo

 

[mikepage]

1). Do you accept that some shafts have less deflection than others?

yes

2). Do you accept that less deflection means more linear energy imparted from cue to cueball?

no

3). If the above are accepted givens, then it follows logically and from deductive reasoning, that more spin must be imparted on an off center hit from a shaft that has less deflection.

The subtle differences due to differences in squirt are not what we're talking about here. Besides whether squirt matters depends on how you do the comparison.

For instance, suppose I'm aiming a squirtless stick straight north and have a tip offset of 10 mm. The ball will move north and I'll have a certain spin-to-speed ratio.

Now if I take a squirty stick and aim it straight north with the same offset, I'll get a little less spin. But importantly, the ball won't travel north anymore. So this is not the right comparison. The right comparison, imo, is to hit the SAME spot on the cueball such that the ball travels north.

So the squirty stick will be facing north north east, and from the point of view of the stick the offset might be 10.5 mm. But from the point of view of the ball traveling north the offset was 10 mm. These two sticks hitting the ball at the same spot and sending the cueball in the same direction will have the same spin, imo.

An interesting question is whether a squirty stick can hit further out on the cueball (from the stick's perspective) without miscuing. I suspect it can.

But again these are subtle differences that are more-or-less understood and are not what people are talking about when they make the --WHOA I can't get used to this tip; it spins the s&*t out of the ball superspin claims.

 

[Bigkahuna]

Interesting response. That leads me to conclude that your "challenge" is merely an exercise to be "argumentative", rather than to prove a theory. In all your years of playing pool, you cannot honestly tell us that you see no difference between two shafts in terms of the ability to apply spin. To do so, will be a lie...and I am willing to bet on that (of course how to prove that you are lying?).

99% of pool players know from OBSERVATION and HANDS ON experience that different shafts can produce different spin-abilities. I played with a friend who had no exposure the the media "hype" of low deflection...etc..etc... He didn't even know who Predator was. But when he tried the Z-shaft, he immediately told me that he was able to impart much much more spin than his regular shooting cue can ever do. And the differences are OBVIOUS and OBSERVABLE. Just because the average joe does not care to put measurements to it doesn't mean it doesn't exist.

Logic and science tells us that different shafts can produce different spin results. But you refuse to acknowledge that because nobody did a controlled experiment in front of your face to prove it to you.....therefore it must be wrong. That is ridiculous.

It's like saying the theory of relativity is wrong because nobody did the experiment in front of you to prove it.....despite the fact that it has been proven mathematically (and by experiment by many scientific groups). But if you are going to pay me $100 to accelerate an atomic clock to 80% the speed of light and then bring it back again to prove to you that relativity exists, then think again.

I firmly believe that you already know the answer to your challenge and that different shafts truely can produce different spin-ability, but you only raise this challenge to be argumentative and controversial....perhaps in an effort to get noticed? Maybe you view everyone as lowly lemmings that you can manipulate as you laugh in the background while you watch them do your silly experiments? Either way, you need to seek help.

By the way, Happy Holidays to you to!

Donald

Listen everyone..............

If I had announced fifteen years ago that a shaft with less weight in the front 4 or 5 inches would reduce deflection I would have been verbally beaten down by all of the people with "common knowledge and logic". Experiments and empirical data is what provided the foundation for the development of the low deflection shaft. You should respect the need to test the things we think are happening.

Theories are dis-proven all the time in this way. Can you believe that in the early 90s men with erectile dysfunction were told there was a disconnection between the brain and the penis. This was "common knowledge" in the medical field. Sometime during the 90s a urologist speaking at a urologists convention injected his penis with a drug in front all the urologists there and aquired an instant erection. From that Viagra and other ED meds. were born and if not the most at least one of the most prescribed medications in this country. Of course, if you ask around nobody takes it, but, that is another story.

While this latest example is certainly not pool related it is a good example of what happens science meets our "common knowledge" or what we think is happening.

 

[Patrick Johnson]

Mike:
...from the point of view of the stick the offset might be 10.5 mm. But from the point of view of the ball traveling north the offset was 10 mm. These two sticks hitting the ball at the same spot and sending the cueball in the same direction will have the same spin, imo.

As often happens, you've given me an "aha!" moment. Of course the effective tip offset is measured in relation to the CB's path, not the stick's direction, because that's the "net" direction of force. Doh!

This is something I've struggled to visualize for a long time. Thanks.

pj
chgo

You guys don't appreciate Mike enough.

 

[8-Baller]

ah...not worth it....

 

[Jal]

...So the squirty stick will be facing north north east, and from the point of view of the stick the offset might be 10.5 mm. But from the point of view of the ball traveling north the offset was 10 mm. These two sticks hitting the ball at the same spot and sending the cueball in the same direction will have the same spin, imo.

For practical purposes, yes. But I think Jaden was correct. The cueball will have acquired slightly more speed (in the north direction) from the squirtless cue, given the same stick speed and efficiency. Therefore, it will have rotated more during impact and this should result in a slightly greater effective tip offset and spin/speed ratio. The effect is very small in theory, but the principle, I think, is valid. Since the amount of squirt seems to be virtually independent of stick speed, the differences between sticks should probably diminish at higher speeds, since the extra rotation during impact reduces the percentage contribution of squirt.

An interesting question is whether a squirty stick can hit further out on the cueball (from the stick's perspective) without miscuing. I suspect it can.

Agreed.

But again these are subtle differences that are more-or-less understood and are not what people are talking about when they make the --WHOA I can't get used to this tip; it spins the s&*t out of the ball superspin claims.

I think Patrick's challenge should include an upper limit (i.e., a percentage) on what is meant by "there is no difference in the spin produced by these cues." If I missed it....

Jim

 

[Colin Colenso]

You guys don't appreciate Mike enough.

I do! :smile:

FWIW: Too many people on this thread are too quick to shout and too slow to use their brains and actually think of a way to demonstrate that differenced in cues can lead to different spin:speed ratios.

It is not a ridiculous challenge. It is a claim that affects many claims by cuemakers and also claims by instructors. For example, I used to believe I could get a higher spin:speed ratio with a lighter cue or a looser grip, but the theory of how spin and speed are produced and my susbsequent trials showed me that this idea, if not completely wrong, is at least quite insignificant.

Isn't there value in not trying to do things that aren't possible, or attempting to achieve some things in an inappropriate way.

Now, in regards to possible mechanisms of creating higher spin:speed ratios I've thought before about the possibility that when a low squirt cue pushes back less against the rotating CB, then the CB loses less of its spin compared to a high squirt cue. Is it not true that a higher squirt cue has consummed more of the rotational energy of the CB?

If true, the question becomes, does this also affect the CB speed in the same proportion?

It would also be useful to know what amount of rotational CB energy is converted into the deflection of the cue. Jal? Anyone?

[edit] Seems Jal is on the same line as me above. I hadn't seen his post before writing mine.

Colin

 

[SJDinPHX]

Just a thought......Mike, Dave, are you there ?

I like to check in on these aiming theads, from time to time. It gives me a gratifying sense of normalcy.
I do have one question. Why do you A.S guys ever start a new thread ?
Every A.S thread I've ever seen has the same content, and the same bickering between the same guys, on the same subjects.
I do agree that some of you (like about two or three) may actually AGREE with something the other says. Then you spend 2-300 posts defending yourself from your detractors. Personally, I think you are all certifiable.
I do not aspire to be a NASA physicist. I just want the ball to go in the hole with some regularity.
Mike, or Mr, Wilson, can't you assign these guy's one continious, never-ending deparment, like NPR, and save the Main Forum for innocent bangers like me who may be corrupted by these people's sense of mathematical (sic) logic ?

Anti A.S.S Dick

 

[desert1pocket]

Patrick, if I remember correctly, you do agree that a cue with lower front end mass will have lower deflection. One side effect of lower deflection is the ability to strike the cueball further from center without a miscue. The further from center you are able strike, the more spin you are able to impart on the ball.

The best test for this I can think of is shooting a stop shot using extreme sidespin, and seeing how long the cueball spins in place. This test would be best performed with the use of Predators robot willy, Bob Muecci's testing mechanism, or some other machine. We can however use extreme differences in shaft delection to prove this beyond a doubt even using a human shooter.

Simply find a predator dealer with one of the weighted front end shafts previously mentioned. These shafts have a piece of heavy metal in the shaft near the tip, and are used as a prop to show how front end mass effects deflection.

Shoot the extreme sidespin shot with a low deflection cue several times and see how long it spins on average. Try to test the limits to how far from center you are able to strike without a miscue. Repeat with test using a stiff heavy house cue. Repeat again with the weighted shaft.

You should be able to see that the low deflection shaft is able to strike further from center ball than the house cue. Using the shaft with the weighted front end, the deflection will be so severe that you will need to hit almost exactly center in order to keep from miscueing, making the shot near impossible.

Patrick, if you can't find a weighted front end shaft, let me know as I may be able to get one to you. Once you have performed the test yourself, and seen the indisputable proof with your own eyes, please donate the $100 to a local charity, and post a reciept for proof.

 

[Patrick Johnson]

I think Patrick's challenge should include an upper limit (i.e., a percentage) on what is meant by "there is no difference in the spin produced by these cues." If I missed it....

Don't you mean a lower limit?

I think the difference must have a practical effect for playing pool. I'm open to suggestion about how to measure that. For instance, using my test (and in order to exceed the "standard deviation" for human-conducted tests), it could mean at least a half diamond difference in the average place the cue ball hits the near rail.

pj
chgo

 

[ftgokie]

Is this one of those hypothetical challenges where the challenger has no intention of EVER paying up, and even if presented with incontrovertible evidence that convinces even industry experts, will still insist there is a problem with the results?

Me thinks so.

Russ

I think you hit this right on the head....

 

[Patrick Johnson]

One side effect of lower deflection is the ability to strike the cueball further from center without a miscue.

How do you know this? I'm guessing it may be true, but a miniscule difference.

pj
chgo

 

[mikepage]

[...]
Now, in regards to possible mechanisms of creating higher spin:speed ratios I've thought before about the possibility that when a low squirt cue pushes back less against the rotating CB, then the CB loses less of its spin compared to a high squirt cue. Is it not true that a higher squirt cue has consummed more of the rotational energy of the CB?

If true, the question becomes, does this also affect the CB speed in the same proportion?

It would also be useful to know what amount of rotational CB energy is converted into the deflection of the cue. Jal? Anyone?

[edit] Seems Jal is on the same line as me above. I hadn't seen his post before writing mine.

Colin

This is something along these lines that I posted back in 1999

Is the range of spin-to-speed ratios larger for a low-squirt stick than
for a high squirt stick? I?m thinking the answer is yes.

For a given hit eccentricity, is the spin-to-speed ratio larger for a
low-squirt stick than for a high squirt stick? I?m thinking the answer to
that is yes also.

First let me give the qualitative argument. Imagine hitting a ball with
maximum right english and a very squirty (lead-weighted) stick. The ball
might squirt out 30 degrees or so as the heavy stick pushes back to avoid
being deflected sideways. The impulsive force of the collision, which
includes a forward component and a sideways component, can be thought of
as simultaneous hits from two hypothetical squirtless sticks. One of
these is directed just like the real stick and produces (if it acted
alone) a ball going in the direction of the real stick with a
spin-to-speed ratio (w/V) characteristic of the tip offset, b. The other
hypothetical squirtless stick is directed perpendicular to the first and
has the same contact point. It produces (if it acted alone) a
perpendicular-moving cueball with a spin-to-speed ratio characteristic of
it?s tip offset (which is related to but different from the first one).
The two velocities add vectorally to produce the observed velocity, and
the two spins add vectorally to produce the observed spin. The key
point is this: because the two velocities are perpendicular to one
another, the magnitude of the resultant is always larger than the
magnitude of either component, and because the two spin vectors point in
opposite directions, the resultant spin magnitude is always smaller than
either component. Here?s another way to look at it. While you?re aiming
and hitting for maximum right english, the part of the stick-ball force
that is producing the squirt is also trying to give the cueball a little
left english. This is a small amount, but it?s enough to cancel out some
of the desired right english.

So am I suggesting a low-squirt stick gives "superspin?" Well it depends
on what you mean by superspin. If you mean a spin-to-speed ratio larger
than w/V = b*M/I, then no. If it means the low-squirt stick gives more
spin than squirtier sticks give, then yes. What I?m really suggesting is
that squirty sticks give a spin-to-speed ratio that is less than that
given by the above equation.

So how big an effect is this?

The above separation of forces is valid by the principle of superposition
of forces. Say you?re aiming in the x direction, and you?re hitting with
right spin with offset b. Then (this equation is from APAPP)

M * Vx = I * w / b.

And for the sideways direction,

M * Vy = I * w / b?.

b? is related to b by

b?**2 = R**2 * b**2

The sine of the squirt angle is Vy / Vx

Sin(t) = Vy / Vx = (w? * b) / (w * b?)

The goal now is to get the total spin (wt) and divide it by the total
speed (Vt) to get the spin-to-speed ratio.

w? = b? * sin(t) * w / b = sqrt(R**2 * b**2) * w * sin(t) / b

wt = w * w? = w(1- sin(t) * sqrt(R**2 * b**2) / b)

Vt = Vx * sqrt[1 + (sin(t)**2)]

The next equation shows that the actual spin-to-speed ratio is the
hypothetical [ b * M / I] multiplied by a factor that is smaller than
unity.

wt/Vt = b* M/I * [1 *( sqrt ( R**2 * b**2))* sin(t) / b] / sqrt[1 +
(sin(t)**2)]

Now sin(t) can be replaced with b / pp, where pp is the squirt pivot
point, and sin(t)**2 can be neglected.

This gives, as a working equation,
wt / Vt = b * M / I * [1 * (R/ pp )* sqrt( 1 * (b/R)**2)]

If we suppose that maximum offset is b/R = 0.5, then this equation gives
the following spin-to-speed ratios (as percentages of the theoretical
maximum) for sticks of various pivot points:

pp (in) spin-to-speed ratio

6 84
10 90
12 92
16 94
24 96
50 98

The bottom line is that a 40-inch pivot point stick can give about 5% more
spin than an (about average ?) 14 inch pivot point stick.

Is this significant? I think so. If it's right [], then it bolsters
the less-squirt-is-better position. Since spin-to-speed ratio is hard to
measure, I think the way to test this relation is to go from average
squirt to lots of squirt. Perhaps clamp a moveable weight to the shaft of
a house cue and measure maximum spin-to-speed as the weight is moved
forward toward the tip.

 

[Patrick Johnson]

Russ Chewning:
Is this one of those hypothetical challenges where the challenger has no intention of EVER paying up, and even if presented with incontrovertible evidence that convinces even industry experts, will still insist there is a problem with the results?

Me thinks so.

ftgokie:
I think you hit this right on the head....

It's a particular shame considering all the honest effort you two are devoting to make this thread useful.

pj
chgo

 

[Colin Colenso]

One side effect of lower deflection is the ability to strike the cueball further from center without a miscue.

I haven't seen that claim proven. Have you got a link or explanation?

Colin

 

[Colin Colenso]

Also got around 5%

This is something along these lines that I posted back in 1999

Is the range of spin-to-speed ratios larger for a low-squirt stick than
for a high squirt stick? I?m thinking the answer is yes.

For a given hit eccentricity, is the spin-to-speed ratio larger for a
low-squirt stick than for a high squirt stick? I?m thinking the answer to
that is yes also.

First let me give the qualitative argument. Imagine hitting a ball with
maximum right english and a very squirty (lead-weighted) stick. The ball
might squirt out 30 degrees or so as the heavy stick pushes back to avoid
being deflected sideways. The impulsive force of the collision, which
includes a forward component and a sideways component, can be thought of
as simultaneous hits from two hypothetical squirtless sticks. One of
these is directed just like the real stick and produces (if it acted
alone) a ball going in the direction of the real stick with a
spin-to-speed ratio (w/V) characteristic of the tip offset, b. The other
hypothetical squirtless stick is directed perpendicular to the first and
has the same contact point. It produces (if it acted alone) a
perpendicular-moving cueball with a spin-to-speed ratio characteristic of
it?s tip offset (which is related to but different from the first one).
The two velocities add vectorally to produce the observed velocity, and
the two spins add vectorally to produce the observed spin. The key
point is this: because the two velocities are perpendicular to one
another, the magnitude of the resultant is always larger than the
magnitude of either component, and because the two spin vectors point in
opposite directions, the resultant spin magnitude is always smaller than
either component. Here?s another way to look at it. While you?re aiming
and hitting for maximum right english, the part of the stick-ball force
that is producing the squirt is also trying to give the cueball a little
left english. This is a small amount, but it?s enough to cancel out some
of the desired right english.

So am I suggesting a low-squirt stick gives "superspin?" Well it depends
on what you mean by superspin. If you mean a spin-to-speed ratio larger
than w/V = b*M/I, then no. If it means the low-squirt stick gives more
spin than squirtier sticks give, then yes. What I?m really suggesting is
that squirty sticks give a spin-to-speed ratio that is less than that
given by the above equation.

So how big an effect is this?

The above separation of forces is valid by the principle of superposition
of forces. Say you?re aiming in the x direction, and you?re hitting with
right spin with offset b. Then (this equation is from APAPP)

M * Vx = I * w / b.

And for the sideways direction,

M * Vy = I * w / b?.

b? is related to b by

b?**2 = R**2 * b**2

The sine of the squirt angle is Vy / Vx

Sin(t) = Vy / Vx = (w? * b) / (w * b?)

The goal now is to get the total spin (wt) and divide it by the total
speed (Vt) to get the spin-to-speed ratio.

w? = b? * sin(t) * w / b = sqrt(R**2 * b**2) * w * sin(t) / b

wt = w * w? = w(1- sin(t) * sqrt(R**2 * b**2) / b)

Vt = Vx * sqrt[1 + (sin(t)**2)]

The next equation shows that the actual spin-to-speed ratio is the
hypothetical [ b * M / I] multiplied by a factor that is smaller than
unity.

wt/Vt = b* M/I * [1 *( sqrt ( R**2 * b**2))* sin(t) / b] / sqrt[1 +
(sin(t)**2)]

Now sin(t) can be replaced with b / pp, where pp is the squirt pivot
point, and sin(t)**2 can be neglected.

This gives, as a working equation,
wt / Vt = b * M / I * [1 * (R/ pp )* sqrt( 1 * (b/R)**2)]

If we suppose that maximum offset is b/R = 0.5, then this equation gives
the following spin-to-speed ratios (as percentages of the theoretical
maximum) for sticks of various pivot points:

pp (in) spin-to-speed ratio

6 84
10 90
12 92
16 94
24 96
50 98

The bottom line is that a 40-inch pivot point stick can give about 5% more
spin than an (about average ?) 14 inch pivot point stick.

Is this significant? I think so. If it's right [], then it bolsters
the less-squirt-is-better position. Since spin-to-speed ratio is hard to
measure, I think the way to test this relation is to go from average
squirt to lots of squirt. Perhaps clamp a moveable weight to the shaft of
a house cue and measure maximum spin-to-speed as the weight is moved
forward toward the tip.

Good stuff Mike!
Though we've got some differences in how we're working out the pivot point that we can discuss later.

Anyway, I did some Grunt Guestimate Round off math (my specialty) that lines up with yours.

Difference in squirt between low squirt and high squirt cue is about 2 degrees which correlates to about 2% of linear force v squirt force difference with a cue offset of about 1/2 inch.

Linear force is equivalent to 5/7 of total momentum, 2/7 is rotational. So 2% of linear force, if taken from angular momentum represents 5/2 x 2% = 5% of rotational momentum.

Hence, a low squirt cue would have 5% less rotation for the same speed with a 1/2 inch tip offset.

This should be observable with high speed cameras, though I'm not sure if it will show up easily on Patrick's test.

If my / our math is correct, then the effect is more significant than I earlier expected. 5% may be quite noticeable and a significant advantage when it comes to holding angles with maximum draw spin speed ratios.

Colin

 

[desert1pocket]

How do you know this? I'm guessing it may be true, but a miniscule difference.

pj
chgo

Read my entire post. The expiriment that I described proves this, and if you bother to try it, you will see that it is not miniscule. Even if it were miniscule, it is a difference, and therefore would win your challenge.

 

[desert1pocket]

I haven't seen that claim proven. Have you got a link or explanation?

Colin

Read my entire post. As I stated, using the weighted front end shaft, you have to hit very very close to center to keep from having a miscue.

 

[Russ Chewning]

While Patrick's test is very thoughtful in regards to accounting for a large number of variables it requires a very light touch to bring the ball back to one rail. Many people might suggest that a maximum spin can only be achieved stroking the ball at a speed that is more than lag speed stroking with a good follow through.

Myself I do not believe there would be much of a difference between shafts. We already know that more spin does not always get you more throw effect and if you want greater spin effect off the rail the amount of english and speed applied will have the greatest effect. So, even if it were that one shaft spun the ball more than the other who cares.

If you want to upgrade "equipment" get a lesson from an instructor and upgrade every thing that makes that cue move!

I just noticed something about Patrick's diagram.

He put the two balls you have to hit between so close together, that if you hit the CB soft enuff to stop within an inch of the far rail, you WILL hit the right blocker ball on your way off the rail.

Patrick...You sir, are an idiot.

Russ

 

[eldowan]

... LD shaft technology ... is only a detriment to people's potential and allows people to succumb to the I want it now the easy way out. I don't think it makes people more accurate, it just has less deflection, allowing people who play by feel to not have to adjust soo much.

This is assinine, If people weren't looking for, and creating, new technology that works more accurately more consistently, I guess you'd be fine driving a Model T around town, and would wonder at the marvel that is the internet. After all, this forum is just the easy way out to a face to face meeting between a group of people who are enthusiastic about pool/billiards, etc...

With automatic adjustments available like BHE, it is NOT more accurate.

When used appropriately, BHE works. period. Efren uses it, most phillipinos use it. It just works. It works a hell of a lot better than LD technology and feel.

Jaden

You are confusing two seperate ideas in this post.
BHE is a technique which means that it can be used regardless of what cue you are using. Just like putting english on a shot, or masse is a technique. BHE relies on feel to determing how much you apply, doesn't it?

LD cues, however, are equipment, and that means that techniques can be -- and are -- applied to them.


Having said that, if you take a cue that shoots with less cueball defflection, and apply a technique like BHE, I'm sure you'd get consistent results.