Cue Angle vs. Squirt Amount?

[Patrick Johnson]

The pics below show the same cue hitting the CB on the same spot while traveling in the same direction.

The cue on the left is stroked normally, straight ahead parallel with the CB's no-squirt path (the dotted white arrow).

The cue on the right is also stroked parallel with the CB's no-squirt path, but with the cue angled as shown (don't ask me how to do that; this is a thought experiment ).

Which one produces more squirt?

pj <- not a quiz - I don't know the answer
chgo

View attachment 63025

 

[iusedtoberich]

I'm going to guess the same amount of squirt.

 

[dr_dave]

The pics below show the same cue hitting the CB on the same spot while traveling in the same direction.

The cue on the left is stroked normally, straight ahead parallel with the CB's intended path (the white arrow).

The cue on the right is also stroked parallel with the CB's intended path, but with the cue angled as shown (don't ask me how to do that; this is a thought experiment ).

Which one produces more squirt (compared with the intended CB path in white)?

pj <- not a quiz - I don't know the answer
chgo

View attachment 41651

This is a "trick question," because the CB path shown is not possible with the cue motion shown in the diagram on the right (even if the cue could be reliably moved as shown). Is that the "answer" you are looking for?

Regards,
Dave

 

[iusedtoberich]

I just tried it on my table, using a guide to try to keep the cue moving in the intended direction. The severely angled stick produced a huge amount of squirt. Like 30 degrees or so.

 

[iusedtoberich]

https://www.youtube.com/watch?v=9v0OCirCgSc&feature=youtu.be

Here is the video. 1 min long for easy viewing.

 

[JasBy]

2 thoughts:

1) if in theory the force vectors at the point of contact are the same (which is what I think you are trying to achieve in this example) then the squirt should be the same.

2) 'In theory there is no difference between theory and practice - in practice there is' - Yogi Berra

 

[dr_dave]

This is a "trick question," because the CB path shown is not possible with the cue motion shown in the diagram on the right (even if the cue could be reliably moved as shown). Is that the "answer" you are looking for?

I think I know what you're getting at now, but I wouldn't call the CB motion resulting from the 2nd hit "squirt" or "cue ball deflection." I would call it a hit in a totally different direction with a simulated swoop or swipe, which isn't as big of a possible effect as some people might think.

Regards,
Dave

 

[ENGLISH!]

The following is a partial quote of Fran Crimi from a thread regarding the swipe stroke in the Instructors Forum.

... Before you can truly experiment with the stroke, you first have to know how to perform the stroke. Then you can study interesting things like, squirt variances ....

...Good luck! It's fun to experiment with, really.

 

[Corwyn_8]

The pics below show the same cue hitting the CB on the same spot while traveling in the same direction

If it is true that squirt is reduced (even if not majorly) by the cue bending, then the second diagram should have more squirt, since the cue can't band as much at the angle to the force.

Thank you kindly.

p.s. trying to break your long-thread-start record already?

 

[Jal]

https://www.youtube.com/watch?v=9v0OCirCgSc&feature=youtu.be

Here is the video. 1 min long for easy viewing.

Thanks a lot for the video. iusedtoberich. It demonstrates that the cueball responds mainly to the cue's component of velocity aligned with its long-axis. The component of velocity perpendicular to that acts, as Dr. Dave put it, like a swoop.

Jim

 

[abbassi]

It's a useless experiment. Results are also useless.

 

[iusedtoberich]

It's a useless experiment. Results are also useless.

I was surprised by the results of my minute long experiment. I expected the CB to go straighter.

I also agree that this was not of any real value. If the results I obtained are true, what do they show or help explain?

 

[whammo57]

It's a useless experiment. Results are also useless.

agree........... you can dissect pool to the Nth degree using formulas and tests by robots.............

in the end, it won't help.... you still have to shoot the shot yourself............

Kim

 

[gutshot]

Try holding the cue against the top of the rail with your hand with the tip a set distance away so that it contacts the cue ball at a set offset to try and help you deliver the cue in a straight line. I suspect you are inadvertently stroking the cue along that vector at impact even though you think you are stroking in a straight line. I suspect the cue will travel in a straight line (parallel to tip offset stroke) if struck correctly even with the cue at an angle. I would also think it would have less squirt than the straight line attack. I could be wrong on both accounts.

Kelly

https://www.youtube.com/watch?v=9v0OCirCgSc&feature=youtu.be

Here is the video. 1 min long for easy viewing.

 

[Patrick Johnson]

The pics below show the same cue hitting the CB on the same spot while traveling in the same direction.

The cue on the left is stroked normally, straight ahead parallel with the CB's intended path (the white arrow).

The cue on the right is also stroked parallel with the CB's intended path, but with the cue angled as shown (don't ask me how to do that; this is a thought experiment ).

Which one produces more squirt (compared with the intended CB path in white)?

pj <- not a quiz - I don't know the answer
chgo

View attachment 41651

This is a "trick question," because the CB path shown is not possible with the cue motion shown in the diagram on the right (even if the cue could be reliably moved as shown). Is that the "answer" you are looking for?

Regards,
Dave

I think I know what you're getting at now, but I wouldn't call the CB motion resulting from the 2nd hit "squirt" or "cue ball deflection." I would call it a hit in a totally different direction with a simulated swoop or swipe, which isn't as big of a possible effect as some people might think.

Regards,
Dave

I'm trying to simulate a swoop stroke at the same angle of attack as a straight stroke, to explore how the squirt for both might affect the outcome. [NOTE: I've replaced the pic of the angled cue with a more realistic one that has a smaller angle.]

The white arrows are the intended no-spin path of the CB (I edited the OP to be clear about that), so it's assumed that the CB will actually go somewhere to the right of that - will it go different directions each way? Why?

My assumption is that the angled cue moving as shown above is a fair simulation of a swoop stroke at the same point-of-contact. Do you agree?

pj
chgo

 

[Patrick Johnson]

I just tried it on my table, using a guide to try to keep the cue moving in the intended direction. The severely angled stick produced a huge amount of squirt. Like 30 degrees or so.

I suspect that's not squirt but "miscue carom". It looks to me like you're hitting too far from center (as viewed along a line parallel with the tip's direction of travel) and miscuing.

pj
chgo

 

[iusedtoberich]

I suspect that's not squirt but "miscue carom". It looks to me like you're hitting too far from center (as viewed along a line parallel with the tip's direction of travel) and miscuing.

pj
chgo

It sounded and felt like a crisp hit, all things considered. It definitely did not feel or sound like a miscue to me. Plus, all the shots went in the same direction. I doubt I could miscue even on purpose and have the ball go in the same direction every time.

But agree, I don't think it is squirt. But whatever it is, its quite consistent.

 

[Patrick Johnson]

It sounded and felt like a crisp hit, all things considered. It definitely did not feel or sound like a miscue to me. Plus, all the shots went in the same direction. I doubt I could miscue even on purpose and have the ball go in the same direction every time.

I think it might be possible if you're hitting the same spot at the same approach angle. It also looks to me like the CB goes in the direction it would if hit on that contact point by another ball (i.e., a near-frictionless collision).

Just spitballing - seems like way too much of whatever action that is otherwise.

pj
chgo

 

[Patrick Johnson]

If it is true that squirt is reduced (even if not majorly) by the cue bending, then the second diagram should have more squirt, since the cue can't band as much at the angle to the force.

My instinct also says more squirt, but I don't have a clear image of the forces involved, so I wonder.

p.s. trying to break your long-thread-start record already?

Let's hope not.

pj
chgo

 

[Jal]

....The white arrows are the intended no-spin path of the CB

Patrick,

Actually, the no-spin path is in the direction of the cue's long-axis. And given that, in the second pic it's not easy to judge how far off-center the tip is contacting the ball. That is, a centerball hit would take place if the long-axis were pointing at the center of the cueball at impact. If it's not, then the spin and squirt will be the result of both the off-center hit as well as the "swoop" (the component of the cue's velocity normal to its long-axis).

In other words, the two pics are of very different situations, even though the tip offsets superficially appear to be the same.

That said, in the second pic, it looks like the tip might be contacting the ball a bit to the left of center (center as defined above). If so, you would get less squirt (the cue's long-axis direction defining the no-squirt direction) than if you stroked straight through at the same offset (offset as defined above).

Jim