Pool ball cut-induced throw and cling/skid/kick experiment

[dr_dave]

Honestly, it baffles me that we haven't found a material better than chalked animal skin in the roughly 200 years since the leather tip was invented.

Maybe it's because leather is so well suited the the task.

Agreed. Chalked leather does perform amazingly well, and over a long period of time (with frequent chalking).

Could you try this with different brands of chalk?

I could, but I probably won't anytime soon. I've already put enough time and effort into what I have posted already. However, you or others could easily do similar experiments. It's not that difficult; although, it does take time to do everything carefully.

Kamui says that theirs reduces deflection.

Do you have a link to this claim, and does Kamui have evidence to back it up?

If they really claim their chalk reduces "cue ball deflection" (AKA squirt), I would seriously doubt this without seeing extremely convincing experimental proof.

If you misquoted them, and the claim was reduced cling instead (maybe because the chalk doesn't stick to the balls as much, or maybe it doesn't increase friction between the balls), again I would need to first see convincing experimental proof before I would believe it.

Would that then mean that it increases friction?

Friction with normal chalk is already adequate to have the cue tip grab and stick to the CB during contact, so an increase in friction really wouldn't do much (except maybe increase the miscue limit; but again, I would be skeptical without first seeing convincing proof).

Regards,
Dave

 

[dr_dave]

Maybe Dave's got some tip measurements that could help us define from a physics perspective what the critical functions of the tip/chalk actually are. That would be amount of friction, energy absorbed, etc...

The purpose for chalk is to help the tip grab the CB during contact. If there is any slip at all during contact, a miscue (or "partial miscue") results, and the OB won't go where expected.

Other things tip properties affect are described here:

cue tip harness effects
cue "hit," "feel," and "playability"
cue tip efficiency

Regards,
Dave

 

[Hits 'em Hard]

The table cloth is Championship; but again, this is immaterial in these experiments.

Do you (and others) think a different cloth would produce different results in this experiment? If so, why?

Thanks,
Dave

Yes I do. The difference between worn and new cloth, along with the different weaves and composition should affect the balls ability to break loose from the cloth which should in turn affect how much cling->throw effect there is. The reasoning I'm using to base this, is that when you do a drawn shot (20 degree cut) on fresh cloth with clean balls, the draw shot will arc backwards due to the ability of the ball being unable to cling to the felt. Same shot with dirty cloth and dirty balls will make the cue ball draw straight back, with little or no arc.

What would happen if you were to apply silicone on the balls at the contact points with the table but not the contact point between the balls? Should be the easiest way to test how much effect the cloth has.

 

[lfigueroa]

Lou, great question about the cue tips. Lets not forget the cloth though. I've always wonder why a worsted cloth as it ages gets that sheen/shiny look to it. Or say the ball trails around the rack area and along the cushions where the ball compresses the cloth upon impact (that ball channel/rut that gets shiny). At first I thought it was just a result of the balls wearing & compressing the cloth only, now I wonder if it's not just the combination of the latter in addition to being impregnated with ball polish residue and other foreign contaminants (skin oils, food grease, chalk and talc etc etc). We all know and understand that almost anything applied to a pool ball will certainly be transfered to the cloth quickly.

I have never used Novus, so I have zero knowledge of what its ingredients are or the effects of its use are. Assuming Novus contains no silicone or "slick/slippery" like residue, it may be possible it's simply cleaning too much as the test results show here with rubbing alcohol or acetone alone, thus increasing ball throw substantially. I use the Aramith cleaner on my set almost daily and I can certainly tell the balls throw ever so slightly more over and after the first hour of use when fresh out of the polisher.

This kind of research is very interesting to me as well and any wisdom about the game and equipment can only be a positive. The bigger problem here is in knowing about it is only one part, the other part is predicting when these affects will alter the outcome of the shot at hand. As players we all have to learn to adjust and adapt to varying conditions and one can usually get an overall feel for the given equipment pretty quickly. Unfortunately as humans we just don't see or notice everything, you know the old saying "hindsight is 20/20", especially after a makable ball is missed. So how would one even begin to compensate for a fast RPM spinning cue ball hitting the object ball, and the corresponding contact point just happens to be where the cue tip left a nasty glob of chalk that could result in up to a +/-200% more or less throw than anticipated? (lol, the thought makes my brain hurt)

Dopc. Always wondering how that last shot was missed!

Well, of course you're right, Dopc, if the balls have a wax residue, over time some or maybe even all of it got to be transferred to the cloth AND the pocket liners.

I use to use Novus and then switched to Aramith thinking who should know better about polishing pool balls. But now, having watched Dr. Dave's video, I don't think that was the right call and am going to go back to the Novus. It's a great product, BTW.

Lou Figueroa

 

[lfigueroa]

I think that if a "residue" (i.e., some form of "wax") is not left on the balls after cleaning, there will be excessive throw (as with the alcohol, acetone, and dish-washing-liquid tests, where the balls are left "squeaky" clean with no residue).


I don't think this presents much of a problem, but I have not tested for it. Silicone spray is another story ... that stuff is nasty and gets all over everything.


I've done some limited tests comparing frozen-combo stun shots with small-gap-combo stun shots, and there was little difference. For more info, see: frozen-ball throw.

Concerning follow vs. stun, follow reduces throw, especially for cut angles in the 1/2-ball hit range. For more info, see effects of follow and draw on throw.

Good questions,
Dave

I feel the Novus Clean & Shine may be different, I'm not sure. It's clear and the consistency of water and I have the impression it is kind of a micro-polishing agent. In any case the balls come out gleaming. FWIW, they have two other products: a Fine Scratch Remover that strikes me as similar to the Aramith product in that it is creamy stuff, but brown in tone and there's a Heavy Scratch Remover too.

Lou Figueroa

 

[JB Cases]

Agreed. Chalked leather does perform amazingly well, and over a long period of time (with frequent chalking).


I could, but I probably won't anytime soon. I've already put enough time and effort into what I have posted already. However, you or others could easily do similar experiments. It's not that difficult; although, it does take time to do everything carefully.

Do you have a link to this claim, and does Kamui have evidence to back it up?

If they really claim their chalk reduces "cue ball deflection" (AKA squirt), I would seriously doubt this without seeing extremely convincing experimental proof.

If you misquoted them, and the claim was reduced cling instead (maybe because the chalk doesn't stick to the balls as much, or maybe it doesn't increase friction between the balls), again I would need to first see convincing experimental proof before I would believe it.

Friction with normal chalk is already adequate to have the cue tip grab and stick to the CB during contact, so an increase in friction really wouldn't do much (except maybe increase the miscue limit; but again, I would be skeptical without first seeing convincing proof).

Regards,
Dave

They say/said reduces deflection. It was part of their advertising.

http://www.kamuibrand.com/billiard-en/?p=1723

http://forums.azbilliards.com/showthread.php?t=328236

 

[dr_dave]

Do you (and others) think a different cloth would produce different results in this experiment? If so, why?

Yes I do. The difference between worn and new cloth, along with the different weaves and composition should affect the balls ability to break loose from the cloth which should in turn affect how much cling->throw effect there is. The reasoning I'm using to base this, is that when you do a drawn shot (20 degree cut) on fresh cloth with clean balls, the draw shot will arc backwards due to the ability of the ball being unable to cling to the felt. Same shot with dirty cloth and dirty balls will make the cue ball draw straight back, with little or no arc.

I agree with you 100% that the trajectory of the CB is very different on slick cloth vs. non-slick cloth (for more info, see cloth effects). The same things happens at faster shot speed (see CB trajectory speed effects).

However, cloth conditions do not affect the OB throw direction. The OB leaves in the same direction regardless of how much the cloth impedes the motion in the throw direction. What would change with the cloth type is how far the OB travels along the throw direction.

What would happen if you were to apply silicone on the balls at the contact points with the table but not the contact point between the balls? Should be the easiest way to test how much effect the cloth has.

Excellent suggestion. The safest way to do this would be to spray the Silicone on the cloth, being careful when placing the balls (with clean hands) to not let any Silicone get on the balls at the ball-to-ball contact point. If you or others do a test without the Silicone on the cloth and then with the Silicone on the cloth, you will see that the throw will be no different (assuming everything else is the same, including the shot speed).

Give it a try,
Dave

 

[Hits 'em Hard]

Am I to gather what you're saying correctly? You haven't done the tests on various cloths? You are then telling me with exact certainty that the cloth has no affect on how much CIT there is? Then you're now telling me I have to do the test you haven't done?

 

[dr_dave]

I feel the Novus Clean & Shine may be different, I'm not sure. It's clear and the consistency of water and I have the impression it is kind of a micro-polishing agent. In any case the balls come out gleaming.

If the balls come out so gleaming, it might be because the "Shine" is partly from a residue left behind, but I don't know for sure.

Since you have given such a great endorcement, I'll try some out when I can find some time to see how the throw compares to everything else. Or maybe somebody else (e.g., you) can test and compare Novus and Aramith and report back with results. The experiment is not that difficult.

Catch you later,
Dave

 

[dr_dave]

They say/said reduces deflection. It was part of their advertising.

http://www.kamuibrand.com/billiard-en/?p=1723

http://forums.azbilliards.com/showthread.php?t=328236

Well, I've seen many unjustified, unproven, and inaccurate "marketing claims" in the past. Again, I will remain very skeptical of this claim until I see extremely convincing proof.

The only way I think this claim could be true is if the chalk it is being compared to allows the tip to slide or partially slide on the CB during contact. But if that happened, the shot would be a miscue (or partial miscue) and the CB direction would be somewhat unpredictable (because it wouldn't slide the same way or the same amount every time). If the tip didn't completely grab the CB with traditional chalk, this game would be much more difficult.

Regards,
Dave

 

[dr_dave]

Am I to gather what you're saying correctly? You haven't done the tests on various cloths? You are then telling me with exact certainty that the cloth has no affect on how much CIT there is? Then you're now telling me I have to do the test you haven't done?

Exactly correct, except for the "exact certainty." I never have "exact certainty." Nobody should ever have exact certainty, except where death and taxes are concerned.

Sorry, but I think the laws of physics strongly back up my arguments.

If somebody makes a claim that seems to violate the laws of physics, the burden of proof is with the person making the claims, not with me.

It's just like the Kamui chalk claims of dramatically reduced cue ball deflection (AKA squirt). I would never accept such a claim without first seeing extremely convincing evidence (since the claim is counter to our current understanding of how squirt works). I could spend a lot of time carefully testing different brands of chalk to determine how much squirt they create, but I won't because I'm fairly confident of what the results would be. Having said that, I would be thrilled if somebody else did such careful experiments and proved me wrong. Then I would be motivated to improve my understanding of the physics until I could explain the unexpected results. And I would learn something in the process.

There is no reason for me to believe that CIT could possibly change with cloth type, so I honestly don't have any desire to spend time on such an experiment.

I'm sorry to be so "honest," but that is the way I see it. I hope you don't take any personal offense, because none is intended.

Please report back if you try the simple test I described.

Regards,
Dave

 

[jtaylor996]

Yes I do. The difference between worn and new cloth, along with the different weaves and composition should affect the balls ability to break loose from the cloth which should in turn affect how much cling->throw effect there is. The reasoning I'm using to base this, is that when you do a drawn shot (20 degree cut) on fresh cloth with clean balls, the draw shot will arc backwards due to the ability of the ball being unable to cling to the felt. Same shot with dirty cloth and dirty balls will make the cue ball draw straight back, with little or no arc.

What would happen if you were to apply silicone on the balls at the contact points with the table but not the contact point between the balls? Should be the easiest way to test how much effect the cloth has.

I think the best way to test would be to repeat this test on top of a sheet of sandpaper and see if it makes any difference. A thin 800 grit would probably be perfect. Maybe sprinkle some chalk on there for good measure.

My guess would be that this could influence the gearing effect of the balls, as it would increase the rolling gearing of the balls to the point where they may slip on the ball to ball gearing (where that gearing would otherwise not be slipping). Something tells me this would reduce CIT a little, at least under those conditions.

 

[JB Cases]

Well, I've seen many unjustified, unproven, and inaccurate "marketing claims" in the past. Again, I will remain very skeptical of this claim until I see extremely convincing proof.

The only way I think this claim could be true is if the chalk it is being compared to allows the tip to slide or partially slide on the CB during contact. But if that happened, the shot would be a miscue (or partial miscue) and the CB direction would be somewhat unpredictable (because it wouldn't slide the same way or the same amount every time). If the tip didn't completely grab the CB with traditional chalk, this game would be much more difficult.

Regards,
Dave

My thinking is how does this chalk affect the ball to ball throw?

 

[jtaylor996]

My thinking is how does this chalk affect the ball to ball throw?

Dave goes over this in this video. If chalk is on the contact point of the 2 OBs, then the throw goes waaaay up.

 

[JB Cases]

Dave goes over this in this video. If chalk is on the contact point of the 2 OBs, then the throw goes waaaay up.

I got that. I was wondering how much it goes up with super chalk vs regular chalk. Since various other substances were checked I thought maybe Kamui vs masters would be worth testing.



Sent from my SAMSUNG-SM-N900A using Tapatalk

 

[Hits 'em Hard]

Exactly correct, except for the "exact certainty." I never have "exact certainty." Nobody should ever have exact certainty, except where death and taxes are concerned.

Sorry, but I think the laws of physics strongly back up my arguments.

If somebody makes a claim that seems to violate the laws of physics, the burden of proof is with the person making the claims, not with me.

So, I asked a question if cloth could or couldn't have an effect on CIT, gave my reasoning why it should. Then you decided that because you know physics about something that hasn't been tested, you've concluded you're correct in your assertion that cloth doesn't affect CIT. Nothing I claimed is said to violate the laws of physics. But without you, or myself testing it, all we have left is a theory. A theory you are willing to publish without testing.

It's just like the Kamui chalk claims of dramatically reduced cue ball deflection (AKA squirt). I would never accept such a claim without first seeing extremely convincing evidence (since the claim is counter to our current understanding of how squirt works). I could spend a lot of time carefully testing different brands of chalk to determine how much squirt they create, but I won't because I'm fairly confident of what the results would be. Having said that, I would be thrilled if somebody else did such careful experiments and proved me wrong. Then I would be motivated to improve my understanding of the physics until I could explain the unexpected results. And I would learn something in the process.

The claims Kamui make are true, to an extent. Due to the way their tips/chalk adhere to the cue ball, and the responding repulsion and spin. They can make a claim that the tips and chalk do help reduced deflection. They are using results to infer a claim that people don't understand. Put a Triangle tip on a cue, chalk it with masters. Run deflection tests, but also record spin. Then chalk it with Kamui. Do the same with the Kamui tip. The Kamui tip will gain more spin quicker through the tests, but will deflect the same. Kamui then infers that by having to use less left or right to achieve the same spin, that deflection is reduced. The same for their chalk. Since it adheres rather than coats, they imply it's able to increase the grab it has and get more spin. Thus you can hit softer, get the same spin and notice a reduction in deflection. An increase in swerve may be noticed too.

But we all know that we could set up a test to show that Kamui is no better than other tips when all we're looking for is data not results.

There is no reason for me to believe that CIT could possibly change with cloth type, so I honestly don't have any desire to spend time on such an experiment.

I'm sorry to be so "honest," but that is the way I see it. I hope you don't take any personal offense, because none is intended.

Please report back if you try the simple test I described.

Regards,
Dave

The is no reason for me not to believe cloth doesn't have an effect on CIT. The same way you tested the properties of balls breaking being altered to show different CIT rates. One would have to believe the ability of a ball to get moved from its original position would alter how much spin it gains and ultimately, how much it throws.

I'm sorry if I'm "honest" too, but I'll be a child too and say that I believe physics agree with me and you have to prove me wrong. So I won't do your test.

 

[JB Cases]

If the question is can the cloth affect the way the ball rolls the answer would be sometimes. I think what Dr. Dave is showing is that the amount of throw variance is constant across surface treatments on the constant surface that is his cloth. The natural assumption using known physics as a guide is that the amount of throw would be relatively constant adjusted for the friction of the surface.

So the balls hit on ice might move over more but the actual friction induced throw amount would be close to the same.

My takeaway from all this is that it would be incredibly prudent to check the amount of throw before starting a match so as to be mentally prepared for it when shots come up where it is a factor.

Given that we never really know what the condition of the balls are the only thing you can do is check it and adjust as much as you can.

I think a lot of players, me included have just taken it for granted and not REALLY checked out the balls before starting a match.

 

[swest]

I think the point is that the vector that represents the resistance of the cloth to OB sliding comes into existence at the moment the OB begins to move, and the direction of that motion is already established...

But, having said that, I think the experiment would be simple enough to perform.

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.
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I'm sorry if I'm "honest" too, but I'll be a child too and say that I believe physics agree with me and you have to prove me wrong. So I won't do your test.

 

[Hits 'em Hard]

I understand clearly what he wants to imply. All he needs to do is look at his results to know what he is trying to imply is wrong. Dirty nap cloth(felt) may cause the balls to gear differently. Same for clean worsted cloth(Simonis 360) may cause the balls the gear differently. It's ignorant to say that there won't be a noticeable change between felts. It's even more ignorant for a college professor to completely disregard a claim just because "he knows." Now, I'm not stating there's going to be a big enough difference to matter. I'm stating that there has to be a difference, and unwillingness to test doesn't make the claims, or potential evidence to change and be wrong.

What effect the difference between clean and dirty, new and worn, and the type of weave has on the balls has to be noticeable. It has to exist from the results provided by the previous experiment show that the friction between objects(balls) has an affect. So why wouldn't the ball->cloth friction not have a say in the results?

 

[Johnnyt]

Thank you very much for the video. That really opened up my eyes on how much an OB can change from 2.2 to 6.5 to 13.6. No wonder why I have problems making balls that were cleaned with Windex. I bet 90% of the players that watch that video are somewhat amazed at some of those results. you must love your job to do all that, and you do it well. Johnnyt