Post a reply

Transferring side to object ball.

Postby Badsnookerplayer

Hi. I hope this is the right area for this. Is it possible to transfer side spin from the cue ball to the object ball? Sometimes when playing a ball along the cushion, it seems to stick better to the cushion if I put side on the white. Am I imagining this or is it recognised that you can transfer side?. Thanks for any help.

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:Hi. I hope this is the right area for this. Is it possible to transfer side spin from the cue ball to the object ball? Sometimes when playing a ball along the cushion, it seems to stick better to the cushion if I put side on the white. Am I imagining this or is it recognised that you can transfer side?. Thanks for any help.


Hi Bad. I'm sorry to see that you have not received a reply yet. It seems the technical threads tend to get overlooked when the tournaments are on so I think your post has been lost among the banter.

I am not a coach by any means, but in 30 years, I have walked around the table a few times and I am quite happy with the state of my game. So I think I can come to you with some authority on this.

The argument about transferring side to the object ball is a very old argument indeed. I don't think any modern player who is recognised as proficient in any of the cue sports would take the position that side does not transfer. As is common for me, I will begin with a bit of history before properly answering your query...

As I understand, the late, great Joe Davis believed that transfer of side was negligible and therefore, inconsequential. In all probability, he was correct (for his time), but that is because back in the olden days, when Joe was young and focused mainly on English Billiards, composition of the balls was still of ivory. Thankfully for the sake of the elephants, modern ball sets are made of phenolic resin, basically, a type of plastic. The really old time players (older than me even, and very few of them still with us) ALL agreed that the old ivory billiard balls NEVER experienced kicks...it is strictly a modern phenomenon ("modern" meaning the last 50, 60 years or so). Do you see a connection here?

With the modern equipment, the coefficient of friction is much higher on the surface of the phenolic balls than the old ivory balls. This can be good and it can be bad, but it DEFINITELY allows the balls to ever-so-momentarily cling together on contact, thus allowing for some fractional transfer of sidespin (and kicks). You are correct....you can make use of this property to help pot balls that are tight against a cushion. However, be aware that by attempting a shot using this method, you will also be open to other pitfalls which may cause the shot to go errant so like so many other things snooker, you must practice, practice, practice to understand the many nuances of this type of shot and use it effectively in actual match play.

The best instruction that I have ever found for this concept of transferring sidespin comes from another late, great snooker/billiards coach and excellent match commentator, the inimitable Jack Karnehm. For your benefit, I posted a clip regarding this on YouTube from a very old instructional video that I have. Unfortunately, the audio is horrible so turn your volume way down low. I hope you can make out what he is saying but I did put a transcript of the most important points in the notes section for you so be sure to read it. In the 2 minute clip that I linked below, Jack is not running a ball along a cushion as you are saying but the same concept of transfer of sidespin applies nonetheless. Every syllable of what Jack has to say is good and relevant information and I use this and much else of his knowledge within my game regularly.

Good luck!

https://www.youtube.com/watch?v=I8p_Xec ... e=youtu.be

Re: Transferring side to object ball.

Postby Badsnookerplayer

Thank you for taking the time to reply with a really informative answer and also posting the link to the video - superb viewing! I remember reading the Joe Davis book when I was young and that is probably why I was unsure about the answer to the question. It makes sense though that the composition of the balls these days have changed the effect of transferred side.

I really am very grateful to you for taking the time to do this and feel better informed and equipped to understand - and play - the shot. When it comes off it is one of my favourite shots as the ball seems to be almost magenetically attracted to the cushion. Thank you

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:Thank you for taking the time to reply with a really informative answer and also posting the link to the video - superb viewing! I remember reading the Joe Davis book when I was young and that is probably why I was unsure about the answer to the question. It makes sense though that the composition of the balls these days have changed the effect of transferred side.

I really am very grateful to you for taking the time to do this and feel better informed and equipped to understand - and play - the shot. When it comes off it is one of my favourite shots as the ball seems to be almost magenetically attracted to the cushion. Thank you


You are very welcome. I enjoy the discourse. However, I do have to disagree somewhat with your analysis of cause and effect, particularly about the bolded statement. Like I said earlier, I believe the transfer of spin issue is settled these days that there is a definite transfer effect. And to be clear, this is a "gear" effect, meaning that the transfer to the object ball will be the opposite of the spin applied to the cue ball, i.e., right hand spin on the cue will induce left hand spin on the object. While I agree with you that properly executed, a well played shot of this sort the ball does seem glued to the cushion, where I differ from your analysis is the cause of this attraction. I don't believe it is the spin that makes the ball stick. Like seen in the video, the usefulness of the applied spin is at the last instant to spin the ball off the jaw of the pocket and into the hole. Without that spin applied, the ball may well rattle the jaws and bounce away. With that said then, what is it that makes the object ball seem to maintain contact as it rolls along the cushion?

I don't think I have ever seen, heard, or read any instruction about this but I have developed my own opinion on the matter over the years. Say that a ball on is in physical contact with a cushion 12 or 18 inches from a top corner pocket. Actually touching the cushion, not just very close. What is the old trick for how to play for this pot? Many people advise to attempt to strike both the cushion and the ball at exactly the same instant, simultaneous as it were, and that in theory should place the white ball perfectly to pot the ball down cushion into the corner pocket. Sounds simple. In fact, that is far from simple and so the wrong way to approach this shot.

Think of it this way. Have you ever tried to place 2 object balls close together, say about 3/4 ball diameter apart, then place the White about a foot away or so. Now, try to make simultaneous contact with both balls. Almost certainly, you cannot do it. Oh, of course, you will be very close to simultaneous, but if you listen closely, you will probably be able to discern the two separate clicks of contact but you will not be able to distinguish which click was first. So then why would it suddenly be easy to contact a ball and the cushion simultaneously? In fact, it is not easy and you can use this knowledge to your advantage.

If you try to hit ball and cushion simultaneously, then surely, you will hit one or the other first most of the time. If you hit the ball first (by just a microsecond) then the ball will push into then away from the cushion and will not go into the pocket. But if you contact the soft cushion first (by just a microsecond), then the White will continue its path sinking into the cushion and will obviously then make the necessary contact for the pot. So it is clear, to have the best chance of potting the ball, you should actually aim to just barely contact the cushion first. And so this is yet another way that running side will help you to pot the ball....you can actually aim to hit cushion first by 1/32", or 1/16", or even 1/8", whatever is your personal feel and control of how much the White will swerve when you apply whatever side you decide to apply. This is where the practice, practice, practice comes in. If you are aiming to hit cushion first by say 1/16" and you are playing just a small amount of running side, say a half tip diameter, then the White will also swerve in its path just slightly in the direction toward which you applied the side. This is completely up to your instinct because if you swerve that White more than the 1/16" that you accounted for in your aim, then White will contact the ball first and you are finished.


Here I have rambled on all this time but I still have not told you what it is that I think causes the "magnetic" effect you mentioned. My best analogy for this comes from driving down the motorway. Imagine driving on a high speed road that has what we goofy Yanks call "rumble strips" (I don't know what the British terminology is so I hope you know what I mean). These rumble strips are just grooves or ridges built into the edge of the road so that if your tire goes over them, your car will vibrate and jar you to pay attention because you are wandering aimlessly in your lane, falling asleep or drunk or whatever. Pay attention to your driving! So anyway, what happens if say your left side tires wander over the rumble strip outside the left side of your lane? Obviously, as the driver, you will immediately feel the vibration and hear the noise. Your instinct kicks in and you jerk the wheel quickly to right and suddenly, you are back in your lane where you belong. But why did you instinctively jerk the wheel to the right, and not the left? What actually happened was when your left tires wandered over the rumble strip, they encountered resistance and therefore, they slowed down noticeably slower than your right side wheels so your car began to veer slightly to the left. With the noise and vibration, as the driver, you suddenly noticed this veering and instinctively you counter-steered in the other direction, just like when you are straightening out from a skid on ice.

So how does this apply to billiard balls? Think of that ball on the cushion just like your car and imagine it has little wheels on it. But it doesn't have a driver to "counter-steer". So when the object ball starts rolling along the cushion like crossing a rumble strip, it is going to feel resistance along that edge that is remaining in contact with the cushion and now it is going to continuously "veer" toward that side. Which means that it is just going to stick like a magnet to that cushion, constantly trying to push deeper into the cushion.

So after that, it sounds like potting a ball down a cushion should actually be very, very simple. Obviously, it is not. The last part of this equation to begin to pot these shots with some consistency is the speed at which you play the pot. Watch the pros when they are faced with these situations. Sometimes, they may strike stronger to play as a shot to nothing or as a half-safe, but when a pro is faced with this type shot that he is absolutely making his best effort to pot, they will always hit it at just a certain speed that seems to work. Too fast and the object ball will probably bounce away; the "magnet" effect will not be able to work. And if they hit it too slow, one or the other of the balls will roll off line or maybe the object ball will just stop in the jaws of the pocket. Again, practice, practice, practice to find out exactly what that special speed is, but for me, I have a certain way that I think of it. When I absolutely am trying to pot this type of shot (which will always come with the risk of leaving the ball hanging for your opponent), then I think to myself that I want to hit at a speed that in the event it does NOT drop in the pocket, the object ball will have just enough pace to rattle and bounce out between 6 and 12 inches (and there is a good chance that it will bounce out and roll along the opposite cushion leaving the same dilemma for your opponent if he decides to play at it).

Sorry for the encyclopaedic response BadSnookerPlayer, but it seems to me that you are looking for answers to improve your game and before long, we should be able to change your screen name! :-D

Re: Transferring side to object ball.

Postby Badsnookerplayer

Hi again and thanks for the further response. I also enjoy discussing and trying to improve my understanding of our game.

The reason I used magnetism as the analogy is (and I am sure I have not imagined this) when played with heavy side and topspin the object ball may briefly (and slightly) leave the cushion on it's way to the pocket but it then goes back in a series of tiny bounces hugging the cushion as though a force is attracting it.

Your example of a pot down the cushion requiring simultaneous striking of the cushion and ball is very interesting. I had always been told - and believed - that simultaneous striking was the required approach but your theory makes sense to me. I will indeed practice and experiment with this approach.

I am not arguing against your advice at all but just to explain a bit why I thought I might be on to something with the spin causing the sticking to the cushion then imagine a red over a black pocket and your cue ball in baulk but away from the cushion. I want to stay on the black so I play with topspin and good follow through. The pot goes in, the white comes back towards baulk but then the topspin grips and it reverses - hopefully holding for the black. This was the effect that I imagined might be happening if transferred side was possible. However, your advice has given me a better understanding of what is actually occurring.

I liked the clever 'rumble strip' analogy and advice on pace to play the shot at. Thanks again - I will look forwards to my next session all the more for your help.

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:Hi again and thanks for the further response. I also enjoy discussing and trying to improve my understanding of our game.

The reason I used magnetism as the analogy is (and I am sure I have not imagined this) when played with heavy side and topspin the object ball may briefly (and slightly) leave the cushion on it's way to the pocket but it then goes back in a series of tiny bounces hugging the cushion as though a force is attracting it.

Your example of a pot down the cushion requiring simultaneous striking of the cushion and ball is very interesting. I had always been told - and believed - that simultaneous striking was the required approach but your theory makes sense to me. I will indeed practice and experiment with this approach.

I am not arguing against your advice at all but just to explain a bit why I thought I might be on to something with the spin causing the sticking to the cushion then imagine a red over a black pocket and your cue ball in baulk but away from the cushion. I want to stay on the black so I play with topspin and good follow through. The pot goes in, the white comes back towards baulk but then the topspin grips and it reverses - hopefully holding for the black. This was the effect that I imagined might be happening if transferred side was possible. However, your advice has given me a better understanding of what is actually occurring.

I liked the clever 'rumble strip' analogy and advice on pace to play the shot at. Thanks again - I will look forwards to my next session all the more for your help.


Hey, Bad. I think your "magnetism" as an analogy is the perfect description of this effect. I have witnessed it exactly the same as you, as a "series of tiny bounces" and I agree that it is euphoric when that shot comes together correctly. There are a hundred things that could have gone wrong, but when you watch it just hugging that cushion on the way to a certain pot, you can't help but smile that you executed just exactly correctly. And far be it from me to profess that I know for certain what the actual cause is; all I know for certain is that the effect exists. I admit that what I stated is just my own opinion with no evidence beyond my own experience to back it up. Every good player needs to look at the data from a variety of sources, test under virtual laboratory conditions, and come to your own conclusion as to what works and why.

I even know one player, far from a great player but he holds his own and pots plenty of balls, and he vehemently disagrees with what I said earlier about the running side helping with this type of pot. On the contrary, he says that check side (or reverse side if you prefer) gives one the best chance at a pot of this type. And the thing is, he does manage to makes these pots quite often. I don't understand how, but you can't argue with facts. It certainly doesn't work for me.


I wait with bated breath to hear DanCat's input. He always has something chipper and upbeat to add to a thread. And I am certain that he will be happy to see you added Big Bill as your snooker idol, may he rest in peace.
Last edited by acesinc on 14 Feb 2017, edited 1 time in total.

Re: Transferring side to object ball.

Postby acesinc

Oh, I meant to add to the above, but I forgot...

As I said, everyone has their own opinions about things like this. I have known more than a few players who insist that this magnetic effect is nothing more than worn out, old cloth that has grooves worn into it from so many balls following that exact path. You don't need to play too much to realize that yes, this is true, tracks like this do exist. But in my time playing snooker since the 80's, I have played on many tables, many conditions. I have owned my own table for over 25 of those years and I have re-clothed it four times now. This effect exists, old cloth or brand new, visible tracks or not.

Re: Transferring side to object ball.

Postby Sickpotter

Personally I've always aimed the shot to hit the ball and cushion at the same time. That is the correct angle to make the shot and it's never let me down.

I actually like shots down the rail but I'm kinda sick like that ;-) Certainly nothing demoralizes your opponent more than smashing in a ball that they thought "safe".

I've played around with running and check side on these kinds of shots and favor check. It feels to me like the more controllable shot as you're not running off a couple of rails like you do with running side.

The thought that running side helps the shot isn't quite true because the shot itself is harder to hit properly. However, when struck correctly it does give you a slightly wider margin of error as you can hit the shot, catch the rail first and still make the ball. Basically it gives you two cuts at the ball, one before cushion contact, one after. You won't make the shot hitting rail first with check side, you really only have one cut at it.

As far as transfer of side from cue ball to object ball......extremely minimal at best and any effect on the shot is negligible. That said I think the likely hood of side transferring from cue to object ball increases with kicks. Any contact with a surface that creates friction would facilitate it and a kick the most likely to provide sufficient friction.

Re: Transferring side to object ball.

Postby acesinc

Thanks for checking in on this Sickpotter. I was hoping you would and wondering what side you would come down on. From what I can tell, you are a very solid striker, hit the White where you mean to and you are probably one of those that CAN make the simultaneous hit when you want to. My own striking is wobbly at best, even on good days, so I tend to play the percentages. With that, I was happy that you confirmed my gut feeling that the running side "gives you two cuts at the ball" and "a slightly wider margin of error"....exactly what I am looking for in these sorts of shots.

Makes perfect sense I suppose that the higher caliber player will like this shot as a check side effort for positional purposes. I can see what you mean about controlling the White better by using a single cushion for position whereas the running side will require position off two cushions which is much less likely to come off as ideal placement, may well come up short off the second and remain tight to the cushion.

I know I ought to put in more hours to solidify my wobbly game then I could feel more comfortable with your technique, but due to time constraints, I am and probably will remain much more of a casual player and will continue to play the percentage shots.

As for the transfer of side, I think I have to very respectfully disagree with you. I thought you played quite a bit of pool as well as the snooker? It seems to me that the good pool players understand the concept of "throw" much better than even the good snooker players do. There is "throw" transferred through induced sidespin from the White, and then there is "throw" created through third ball contact at an angle. So many "dead plants" are missed by amateur snooker players because they don't understand that the concept of throw will push the object ball off line. And no matter how you slice it, any throw is really nothing more than sidespin that has been induced on the object ball pushing it off its natural line.

I don't claim to be any sort of pool player at all, but I have the greatest respect for Dr. Dave and all of the various studies he has done regarding the science and physics of pool and billiards. I hold your opinions on things in the highest regard but I have to retain my own opinion that more sidespin is transferred than I believe you are accounting for.

Re: Transferring side to object ball.

Postby Sickpotter

I think we're talking about three subtly different things here, cue ball throw vs object ball throw vs side actually transferring to the object ball.

Certainly there is some object ball throw when you talk of a plant with two frozen balls but in that scenario the throw is introduced by the contact between the two plant balls or perhaps the simultaneous 3 ball contact, not by the cue ball having side on it. You can make a plant throw without any side on the cue ball at all.

I think friction between cue ball and object ball will aid side transferring from one to the other but seldom is there sufficient friction for this to have a noticeable effect. How often (if ever) do you see the object ball rotating on a vertical axis and also on a horizontal axis as it travels to a pocket? If side transferred in any significant way from cue ball to object ball wouldn't that be common?

Interesting discussion, we should probably consider separating throw and transfer of side into two separate topics, maybe even three. Cue throw, object ball throw when using side and transfer of side from cue ball to object ball.

Re: Transferring side to object ball.

Postby acesinc

I really want to get into your brain here to be sure I can learn something. So I want to be certain that I understand you, but I have to admit to confusion about your very first sentence...

Sickpotter wrote:I think we're talking about three subtly different things here, cue ball throw vs object ball throw vs side actually transferring to the object ball.


I don't know what you mean by "cue ball throw"....does this just mean the natural swerve that will occur anytime the cue ball is struck outside its center axis? When I use the term "throw", I only use it to describe the action of the object ball, not the cue ball.

To me (and I admit that I may be using the term incorrectly), throw refers to the object ball traveling off the line that is expected of it. This can happen in one of two ways, but it always comes down to the fact that the object ball has some sidespin imparted to it that causes it to wander off line. (That is what I meant in my earlier post when I said, "And no matter how you slice it, any throw is really nothing more than sidespin that has been induced on the object ball pushing it off its natural line.")

The two ways that I envision the sidespin being imparted to the object ball are: 1) gear effect transfer of cue ball spin to object ball, and 2) spin induced by "frozen balls" being contacted at an angle (whether by the cue ball or by a third object ball, frozen or not). In either case, in my opinion, the final object ball is "thrown" off its expected line of travel because it has spin imparted to it due to the circumstances of the shot, and so just like a cue ball with side applied, that object ball will "swerve" just slightly so its path will be different than expected by the uninitiated. (For anyone else reading this, have you ever played to a "dead" plant, absolutely cannot miss, strike the first Red of the plant at an angle, then the object Red rattles the jaws and bounces away? How did that possibly miss? THIS is how:)
https://youtu.be/rO85r7nLQ9o?t=113

So in the case of 1) above, I believe gear effect side will transfer from the cue ball to the object ball to a noticeable degree. And I think this is where we differ. Certainly only a small percentage of the spin will transfer, but I believe it will have a noticeable effect. (I refer you again to the video by Jack Karnehm earlier...you can see how the Black hits the jaw of the pocket and just spins right in, absolutely no doubt about the pot. Jack talks about hitting the Black thicker than you would think so that the fuller hit allows you to play better position. What he does NOT say is that White (with right-hand spin) will contact Black fuller, some of the spin will be transferred (as left-hand spin) to the Black, thereby causing the Black to travel a bit to the left of its expected travel line, to the jaw of the pocket (remember he pointed that he was aiming about an inch outside the jaw of the pocket). And lastly, the imparted spin on Black kicks it strong left off the jaw into the pocket. (Last note, Jack uses the phrase, "...the side will throw the Black ball into the center of the pocket." I don't think he is using the term "throw" in the same sense as I am here referring to the transfer of spin and consequently the change in the expected path of object ball. I think he simply means the Black spins off the jaw and is thrown into the pocket, nothing more. "Throw" is a pool term I learned from the now late, great Robert Byrne; it was not common snooker parlance when I lived in England decades ago (around the same time as that video) so I don't know if that term is used at all currently in snooker terminology.)

In the case of 2) above, the frozen balls have a common surface area where they touch so there is a resting friction between them, "static friction" I think is the proper term ("static" meaning "non-moving", not "static" in the electrical sense). When the first Red ball of the plant is struck at an angle, these balls try to hold on to each other at that static friction point thereby inducing a spin onto the second Red ball (the one NOT struck by the cue ball). That spin is imparted in the same direction that the cue ball is traveling so that the second Red will be "thrown" off the expected line of travel toward the same direction as the cue ball travel. But it was still caused by side spin.

Please let me know what you had in mind about "cue ball throw". Thanks.


I know I have taken us way out of the realm of the original post, and I apologize to BadSnookerPlayer for that.
Last edited by acesinc on 15 Feb 2017, edited 1 time in total.

Re: Transferring side to object ball.

Postby Sickpotter

I was thinking of cue ball throw as in the distance it's deflected off line by striking the cue ball off center.

This is pretty much governed by the type of cue you're using, a common thing players look for in pool is what is called a low deflection shaft. Very desirable as the more deflection you have the more you need to compensate with alignment and pace of shot.

When you talk about an object ball being thrown by use of side on the cue ball. Is that cue ball throw or object ball thrown?

Are we certain the side is actually throwing the object ball or has the cue ball swerved to the proper contact point by the time it reaches the object ball?

Tricky subject for sure, I think some freeze frame/slow-mo film should give a definitive answer. TBH I'm a little surprised no pro has looked into this but then again, sometimes it's bad to over-think something ;-)

Re: Transferring side to object ball.

Postby acesinc

Everything I know about it comes from Byrne's Standard Book of Pool and Billiards. He points out the transfer of spin by freezing cue ball to object ball. Then, you can throw the object ball one of two ways, both illegal as far as Snooker is concerned (push shot). First, if you strike directly in the same line as the balls are aligned with, say, right hand side on the cue, the object ball will drift noticeably to the left (and yes, you will see the spin if you line up a stripe ball vertically). Second, if you strike centerball but at an angle to the line of the two balls, you will see the object ball drift to the same direction your cue was pointing and again, you could see the imparted spin with the stripe. Dr. Dave does have a lot of videos posted of this nature. I will be very surprised if you have not seen them.

Everything else is really just extrapolated from that information. Of course, greater distances, and less spin will transfer, so it is all a matter of degree, but I think the effect is undeniable.

I am going to get a few frames of snooker in over the next few hours, so if you respond, I won't see it for a while. :happy:

Re: Transferring side to object ball.

Postby Badsnookerplayer

Hi,

Acesinc - no need to apologise for the thread drifting as I have enjoyed the discussion and it has helped my understanding and deepened my thinking on the game.

In fact my head is starting to hurt as I am thinking about this way too much. The thing that has really stumped me is that I have always played the shot with running side and - as Sickpotter pointed out - this can come at the cost of ideal position at times. However, if the gear effect does transfer spin then running side would surely put opposite spin on the object ball to the detriment of the pot. This is contrary to what I have observed with the mini bounces inducing the object ball to stick to the cushion when physics would suggest the opposite. I am not sure I have explained this well enough but I will be at the snooker hall tomorrow so I will experiment with the shot using both running and check side. I will also ask if they have a striped or spotted ball so I can report back further.

I think this question epitomises why snooker is such a fascinating game to me. I have been playing for 28 years and I am still baffled by some of the subtleties and nuances. I remember reading in Joe Davis book 'How I play Snooker' that he felt that nobody would ever get to 'the end' of snooker and I think he stands correct to this day.

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:Hi,

Acesinc - no need to apologise for the thread drifting as I have enjoyed the discussion and it has helped my understanding and deepened my thinking on the game.

In fact my head is starting to hurt as I am thinking about this way too much. The thing that has really stumped me is that I have always played the shot with running side and - as Sickpotter pointed out - this can come at the cost of ideal position at times. However, if the gear effect does transfer spin then running side would surely put opposite spin on the object ball to the detriment of the pot. This is contrary to what I have observed with the mini bounces inducing the object ball to stick to the cushion when physics would suggest the opposite. I am not sure I have explained this well enough but I will be at the snooker hall tomorrow so I will experiment with the shot using both running and check side. I will also ask if they have a striped or spotted ball so I can report back further.

I think this question epitomises why snooker is such a fascinating game to me. I have been playing for 28 years and I am still baffled by some of the subtleties and nuances. I remember reading in Joe Davis book 'How I play Snooker' that he felt that nobody would ever get to 'the end' of snooker and I think he stands correct to this day.


Hi Bad, I am back from a short session on the table. A short 30 and a couple 20's in 2-1/2 hours of friendly match, not practice. Not great, but I am happy. It is a tough table, and with the opponent I have, it is always what I call "arbitrary snooker"....no colours anywhere near spots, balls scattered, opponent primarily tries to take shots away from me rather than actually scoring....makes it tough to run more than a few balls in a row to try to tidy up the constantly sloppy table.

Anyway, I love your attitude! I bolded a couple of your statements above. To the first bolding...why would you think that? Let's define an exact scenario: say we are potting a Red that is touching top cushion about one foot from the top right corner pocket and White is somewhere near Black spot. We want to leave on Black on spot. So....Sickpotter correctly suggests that check side will hold White nicely for Black. But that comes at the cost of a precise, perfect hit required. Aces and Bad say top right seems to assist the pot, but that comes at the cost that White must then run to the side cushion and out some....probably not ideal position for Black.

With all that defined, now Bad, let's just consider the side component of the spin placed on the White. I believe the best chance to pot comes with a touch of right hand side on White and striking cushion ever so slightly first before the Red. This in theory will transmit a certain amount of left hand side on the Red.

Now let's change it up...say you place the White in the exact position that Red is and all you are trying to do is to pot the White but you CANNOT use center ball. What would you choose? Left or Right? If you choose Right, the White will surely swerve out to the right a bit and rattle the jaws. If you choose Left, then the White will constantly be trying to turn into the cushion (in a series of little bounces, I might add) and in addition, when White reaches the pocket, it will be thrown into the pocket by the side as suggested by Jack Karnehm.

So I disagree with the bolded assessment....running side would (if it does anything at all) assist with potting the Red in the original set up.

As for the second bolded statement, I read (and own) that book as well! And that statement also stuck in my head all these years! Love it!

Re: Transferring side to object ball.

Postby Dan-cat

This is an ace thread.

I won a pool game in Colombia by cutting the black down the cushion which technically wasn't on. It was less than 90 degrees. I used side to bend the ball whcih meant as it came to the object ball it was able to thinly cut it down the cushion.

The guy I was playing was astounded. 'That was impossible!' He exclaimed.

I've always used running side to pot those balls along the cushion on the snooker table and experienced those little bounces. But what Acesinc is saying about the gear effect and sickpotter about the positional side - it makes more sense to use check side! My mind is blown at this point. Experiments needed.

A lot of these tricky techniques I learned from a Jimmy White instructional book which was probably written by Clive Everton with some input from Jimmy (pretty sure he ghost wrote most of those books in the 80s.) I'd love to find this book again <heads off to google>

Yes Badsnookerplayer - I've got the Joe Davis bible too. He totally changed the way I play little screw and stun shots.

Re: Transferring side to object ball.

Postby acesinc

Crazy Dan! Always playing to (and potting) the impossible shots off the lampshade! Can I book you for exhibitions?

Back to some of Sickpotter's points...so if I am not mistaken, what you are calling cue ball throw is what I have always just referred to as "swerve". I suppose "swerve" as a term is really meaning that one is specifically curving White around an obstruction such as to escape a snooker, but I have always called it "swerve" even if it is just a regular shot that has a little side played on the White. The White will ALWAYS swerve to a greater or lesser degree depending on the amount of side and pace of the stroke. This natural swerve always has to be accounted for in the stroke and I think this is one of the intangibles that makes the great ones great. They account for this swerve perfectly, but chances are they cannot explain to you how they account for it. I think it is mainly gut instinct and muscle memory from previous experience.

As for the "low deflection shafts", I have heard of that before but it doesn't mean anything to me really. I imagine it is in the materials, like the modern golf club shafts. I don't own a pool cue (I mean the big logs for American pool...you are in Canada, right?) so on rare occasion when I find myself on a pool table, I just use a house cue. Most of my many snooker cues (and especially my favourite one) are nearly as old as I am, probably cut down and shaped with a stone ax by the natives so there is certainly no technology there.

Here are a couple of perfect example Dr. Dave videos to demonstrate the points 1) and 2) I made in the earlier post. The first one is kind of long and somewhat repetitive so if you want, you can just watch the first minute or so for the first shot, then jump to the 4:55 mark:

https://www.youtube.com/watch?v=4PGXUld5A24 (you can jump to 4:55)
https://www.youtube.com/watch?v=Y04u3FWad7k

Watching the stripes, it becomes quite obvious what is actually happening. On the snooker table of course, we can't see any of this with plain colour balls so I was confused at one of your earlier posts about "seeing" the effect. With the pool balls in the video above, the effect is undeniable.

Re: Transferring side to object ball.

Postby acesinc

Oh, and a P.S. to my above post:

I should point out that I still don't believe that the transfer of side from cue ball to object ball is the CRITICAL factor of helping to make the pot along the cushion easier (note that I agree with Sickpotter that check or reverse side is "better" for positional purposes, but I still believe the running side makes the pot "easier"). As seen in the Dr. Dave videos, side will transfer but sort of like gravity (to extract from another, less important area of physics beyond billiards), the effect is rapidly diminishing over distance. Not in the video, but experience will show you that the effect is also diminishing as the angle of approach becomes more shallow. A full ball contact will transfer a lot more spin to the object ball than just a glancing blow.

So in the example I defined above, I still believe that the pot is assisted through the "rumble strip" effect that I described (though the spin transfer may help the pot when the object ball hits the jaw of the pocket).

Re: Transferring side to object ball.

Postby acesinc

I figured I would bump this thread as it has gone stagnant. Also, because I stumbled across a video from a couple months ago, one of my regular very interesting sessions with my kid, relevant to the discussion here. He absorbs knowledge like a sponge and his cue action is already superior to mine so before long, he should be quite the Terror on the Table!

This is a good example of the third ball throw concept mentioned earlier. The "plant balls" are not quite touching each other so this shows that the throw effect will transmit even across at least some distance. The plant is definitely not lined up for a straight pot.

The whole video is about 3-1/2 minutes...if you are in a hurry, the most important bit runs 0:40 to 1:40, the rest is just a prefix and a suffix to the main statement.

https://www.youtube.com/watch?v=cBASJE2 ... e=youtu.be

I know there is some way to embed the video right into the thread here but I am better on a snooker table than I am on a computer so that should explain why I don't know how. I have to just stick to giving you a link.

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:This video purports to 'prove' that side is not transferred. Do you have any thoughts? The only difference between this situation and the one I described at the start of the thread is that the object ball is not on the cushion.

https://www.youtube.com/watch?v=4B4f_IDFips

I would be interested to hear what people think?



This comes as a complete surprise to me that Kevy62 maintains this opinion. I have watched quite a few of his videos in the past and have been very impressed; he obviously is a very good player and keen to assist others in learning the game. Why he would take this position of non-transference, I cannot imagine. Even within this ambiguous video that purports to claim that spin does not transfer, there is evidence that spin does in fact transfer. To be clear, no one is saying that spin transfers completely; it does not, only a small percentage transfers. I am not aware of anyone doing any studies (in fact, I doubt accurate studies can even be done as conditions would simply be too variable to produce accurate data), but I would suggest perhaps somewhere in the neighbourhood of 5 percent or less meaning that if I imparted spin of 1000 rpm (revolutions per minute) to the cue ball, good transfer may cause the object ball to begin spinning at, say, 50 rpm....that is less than 1 revolution per second, not much indeed.

The evidence of spin transfer within Kevy's own video? Go to the 1:28 mark and watch the last shot, but first let me set up your mindset before you watch...
I am far from a great player myself, but I have reached a point where positioning the white ball exactly where I want it to be is critical to my game and my confidence in my potting is greatly improved over the last couple years. With that said, for positional purposes, I will quite often pot a ball to a specific part of the pocket (I basically divide the pocket in my mind into "left half/right half/center" and aim the object ball EXACTLY where I need to for White ball control. Now, undoubtedly, Kevy is a far superior ball striker to myself. Sometimes, I succeed putting the object exactly where I want in the pocket; often I don't. With Kevy's ball striking ability, setting up the shot he is setting up (simple Blue in middle pocket), there is no doubt in my head that he can and will mindlessly pot the Blue (stripe 10 in the video) 99 out of 100 times dead center in the pocket.....except he doesn't. He is clearly putting left hand side on White, we have every reason in the world to believe that he hits the 10 ball full in the face on center (note the trajectory of White on this shot....stays on line; the other shots were struck at slight angle, not full in the face). Yet the 10 clearly and undeniably drifts to the right, strikes the right jaw at a slow speed and so drops in the pocket. Played at any pace, that 10 ball may not even have dropped into the pocket, just rattled and bounced away. Make no mistake, this sort of thing is EXACTLY why a professional player will sometimes miss what would seem to be quite a simple shot; the object ball moving off the line he expects due to spin transfer.
You have probably already watched the video, but now is the time that you should go back to it and specifically watch the shot beginning at about 1:28.

Referring back to my earlier videos from Dr. Dave, Dave Alciatore does not just refer to himself as "Doctor" in a narcissistic sense...he actually holds a PhD in Mechanical Engineering and is a well known, oft published, public figure in the billiards world and in fact a professor of mechanical engineering at Colorado State University. I daresay, there is some weight behind Dr. Dave's words. Mechanical engineering is my field as well (far, far, far from a "Doctor" however) so Dave's explanations and methods make absolute perfect sense to me.

If someone really wanted to "disprove" spin transfer in a video, it would be easy to do....all it would take is a camera, a table, a couple of stripe balls and a little silicone or teflon spray off camera. There is also an old bar trick where you could easily dupe a mark out of quite a few quid with a similar trick using bodily fluids as a lubricant, but we won't talk about that in polite company.

I will try to get some time this week and make my own video similar to Kevy's to compare these spin transfers....
Last edited by acesinc on 19 Feb 2017, edited 1 time in total.

Re: Transferring side to object ball.

Postby acesinc

P.S. - and this is specifically directed toward Sickpotter...
In reviewing this Kevy62 video, I also clicked on a video from NeilMaxMan, another YouTube poster that I admire and respect. I had not seen this video previously, entitled "snooker pro tips 42, throw of the white when applying side" and in it, he specifically defined "throw" as the movement of the White ball when side is applied. So that sounds exactly like what you were saying with "cue ball throw".

This is a common problem between the Pool world and the Snooker world: language and terminology. In my personal experience, I initially learned (American) Pool when I was just a little kid, 8 or 10 years old, but just for fun, nothing serious. Then at 19 years old, I moved to England and learned and loved Snooker. Today, I consider myself fully an American Yankee Snooker Player, and I very rarely play a game of Pool. But knowledge from Pool is useful to Snooker also, and I have picked up a lot of Pool wisdom over the years. As such, I learned the term "throw" more years ago than I care to remember within the Pool context, not Snooker, and like I said earlier, to me, "throw" is the subsequent movement of an object ball, not the cue.

This is something brand new to me that I had never known before! :-)

Re: Transferring side to object ball.

Postby acesinc

Here is my video reply to the video post earlier by BadSnookerPlayer. My camera is permanently set up so it is not easily moved around. All I could do is zoom in closer so you could hopefully see how the spots on the object ball react. This is far from a proper laboratory experiment, not nearly enough trials, conditions not well enough controlled, and I could not possibly enter the experiment with an open mind as I have already stated my preconceived opinion. So you can make of the video what you will. This was strictly a "single take" affair; no practicing, no script, I just wanted to see what would happen. I had a few minutes in the work day and took care of it. There is a lot of dead space between setting up the shots, so you will be best to skip ahead 20 or 30 seconds between each shot. And you will probably need to slow down to minimum speed to see but the "wobble" of the critical dot is the indicator of the transfer of some spin and that the object ball has slightly changed trajectory. Compare this wobble to the stable dot of the center ball strikes.

The last three minutes are the best part.

https://www.youtube.com/watch?v=HNpQFqNqlic

Re: Transferring side to object ball.

Postby Badsnookerplayer

Thanks Ace - this is an interesting video. I have viewed it at slow speed and the wobble is definitely visible when you indicate that you are applying side .

The last three minutes are great but I don't understand how you are controlling the trajectory of the measle ball! I cannot see from the video where you are aiming on the cueball but presume that you are adding spin when you are successful?

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:Thanks Ace - this is an interesting video. I have viewed it at slow speed and the wobble is definitely visible when you indicate that you are applying side .


Yes, I agree. Unlike Kevy with a portable camera in a public setting (I would be the guy sitting at the bar in the background), my camera is basically a permanent mount so I could just zoom in a bit and hopefully, that is good enough to see what is happening. And "wobble" is really all that it is. If you look at the cue ball either in Kevy's video or in mine when the side is applied, you obviously see the cue ball continue to spin in place as it sits there until eventually, friction from the cloth slows and stops it. A child's toy top is similar (do kids still play with those these days? or is there an "app" that you put on your five-year-old's smart phone so he can watch a top spinning on the screen? As have I said in the past...I am from the age when they quarried the slate for the billiards table on the backs of elephants so sometimes, "technology" baffles me), the top will spin for a very long time because it has a single, very small point of contact so loss of momentum through contact with the surface it is on is very slow. Relatively speaking, a billiard ball spinning on a thick snooker cloth will lose its momentum rather quickly through friction.

And therein is the reason that some people, apparently including Kevy, believe that the spin does not transfer...they must believe if the spin transfers, then one should be able to look at the object ball and also see it spinning like a top like the cue ball. It doesn't work like that; all you will get out of the object ball is that wobble...and a change in direction. In fact, the change in direction is EXACTLY the same principle as the change in direction detected when a massive kick occurs, it is simply a matter of degree....the change in direction from a massive kick is like a giant hurricane on the Atlantic, while the transfer of spin to the object ball is like a gentle 20 mph summer breeze.

So why do we get that wobble? and why does it cause a change in direction? Think of it this way....have you ever driven your car in wintery weather, slow speed, and maybe there are some patches of ice on the road so your tires are going to slip when you drive over those patches? If someone reading this lives in a tropical country and never experienced driving on ice, you have to use your imagination because this is the best analogy I have found. So say you hit an ice patch but you try to turn the steering wheel to the right a little bit. Your tires have turned but you just continue moving in a straight line across the slippery ice. Then suddenly your tires come to the end of the ice patch and hit dry pavement once again. What happens? The friction of your rubber tires on the now dry road surface "grab" onto each other and because the tires are facing a different direction from the line of travel, you feel a jerk and suddenly, your car is traveling on a new trajectory, new line of travel from previously.

THAT is exactly what happens when the spin transfers. Imagine the very small, exact point of contact between the spinning cue ball at the very precise moment when it contacts the object ball, one surface is moving, spinning; the other surface is static, sitting still. There is a coefficient of friction between these two surfaces (absolutely calculable at any given instant, but still always an intangible variable because so many different conditions and circumstances can change that coefficient of friction at any given instant; for instance, a minute particle of chalk dust gets squished in between them) so that at the precise moment that the surfaces make contact, they will "grab" onto each other the same way your rubber tires "grabbed" the dry road surface. So the object ball has two different force vectors applied to it......a very large one transmitted by the linear momentum of the cue ball so the object will begin traveling in a straight line in the direction it is pushed; but then there is also a small vector of force of the surfaces catching each other and beginning a spin on the object ball. As stated earlier, this spin speed (rpm) will only be small fraction of the spin speed of the cue ball and here is the important bit.....that spin really won't last long at all, only a fraction of a second before that force vector is worn off by friction with the cloth, then all we will see is the cue ball rolling in a straight line, but altered from its expected direction as clearly shown by the wobbling dot.

The transferred spin wearing off so quickly can be analogized again by the spinning child's top. Imagine a top that does not taper down to a pinpoint on the table surface, but instead, it has a large 1 inch diameter cylinder at the bottom so there is a large circle area of contact with the table. Relatively speaking, there will be a lot of friction that will quickly stop the top from spinning but the point is that the top WAS in fact spinning in the first place just like the object ball was in fact spinning in the first place, it just wore off very quickly. Now, as for the slight change in direction of the object ball's expected path? Think back to another analogy we discussed. The large force vector, the "push" of the cue ball against the object ball is like the strength of the hurricane. The transfer of side spin is like the gentle breeze. Imagine a hurricane that is heading directly toward some uninhabited island in the Atlantic Ocean. Everything can be precisely calculated with the proper maths. The exact center of the eye of the storm will pass directly over one of the only two coconut trees standing on the middle of the island. But suddenly, out of nowhere, this nasty, gentle 20 mph cooling summer breeze comes out of the west and pushes ever so gently at the side of the hurricane! What is the end result? The trajectory of the hurricane has been altered ever so slightly, and the exact center of the eye of the storm now instead passes over the OTHER coconut tree standing just a few feet away.

This is what actually happens when spin transfers. It is a small, but demonstrably noticeable effect.

Re: Transferring side to object ball.

Postby acesinc

Badsnookerplayer wrote:The last three minutes had me perplexed - I have never seen that but now I can see what you did there. When you miss the pot, you are acting like me. But when you pot it, it is you striking.


That is correct. Kevy could have done this routine with the guy sitting at the bar if one of them were in possession of the required knowledge and the other was not. If you can fathom this concept of spin transfer and thoroughly understand why things happen the way that they do, then you would also be able to pot the measle ball (or whatever ball you put in its place). Every. Single. Time.

Re: Transferring side to object ball.

Postby Badsnookerplayer

Hi Ace,

The video was very illustrative and I have learnt from it. I had always imagined that - if spin was transferred - then if left hand was applied to the cue ball then the object ball would spin in the opposite direction around a vertical axis. In fact the effect is much more subtle as you explained in an earlier post which leads to the wobble. It appears that the object ball is 'turned' slightly and then continues in a forward roll. This would explain the motion of the measle to me and it would appear as you say that any transferred spin 'dies away' rapidly.

Again, I like your analogies and skill at explanation. Would I be wrong in questioning your assertion that there is a coefficient of friction in play at the instant of contact? It is only a question and I am not confident in this but if we view the balls as perfect spheres then the point of contact is just that - a point. In effect there is an infinitesimal point of contact and does a coefficient of friction apply in this non-planar situation? I have no doubt that there is effective friction due to the irregularity of the surfaces on a microscopic level but I wonder if it is actually calculable??

I am very interested that you raise the subject of kicks and I hesitate to raise any theories or questions when there have been much deeper studies than I could hope to achieve. However, it occurred to me earlier in the thread that if spin can be transferred then we should also consider top and backspin. Is it the case that a possible explanation for kicks might lie in the following (at least some kicks). I have not considered or seen this theory before but may be mistaken.

So, if we play with top spin and spin is transferred then at the moment of contact the cue ball will attempt to impart backspin to the object ball - the gear effect. This opposes the forward momentum imparted by the linear motion of the cueball and to my mind would give rise to a likely reaction. I have not seen any empirical evidence as to whether most kicks occur when the cueball is given topspin but anecdotally I seem to recall it rarely occurring when screw is applied in which case the transferred spin would agree with the forwards momentum. I shall see what I can find on youtube.

As always I would be interested in your thoughts as I think you have a very good understanding of the physics at play and a skill for explaining.

Re: Transferring side to object ball.

Postby acesinc

BadSnookerPlayer, your screen name should be, "GreatConceptVisualizer"! You are an astute observer! Open minded and very logical indeed. Let me start by saying that everything I have stated in this thread and others is really nothing more than my own interpretation of the physics needed to explain the actions and reactions of little spheres on large green surfaces. Unlike say, golf, it seems to me that there is just not the capital available for intensive R+D and scientific inquiry as to what is really happening so we must all make our own way in these matters based on what we see, hear, read, believe. If only we could convince the people in Switzerland that it is important that we borrow their little CERN device for a few days so we could more intensely scrutinize the collisions of little plastic spheres. Ahh, to dream....

So I will address your points directly within the context of your post. I will bold my responses because I can't figure out how to change font colour...

Badsnookerplayer wrote:Hi Ace,

The video was very illustrative and I have learnt from it. I had always imagined that - if spin was transferred - then if left hand was applied to the cue ball then the object ball would spin in the opposite direction around a vertical axis.
Certainly, this would happen...if we were to pound a nail through the White ball to act as an axle and prevent the strong linear motion vector from occurring. You must consider that ANY motion is the summation of ALL possible vectors and each vector will have an influence in proportion to its strength. The linear "push" vector is by far the strongest. Then there is the far weaker "spin transfer" vector. And a third but also significant vector (and certainly not the last) will be the "resistance to linear motion" vector which is the resistance caused by the cloth and table surface. Consider an absolute centerball, full in the face strike of cue on object. White SLIDES into object, no spin at all. What does object do? Obviously the push vector is applied so object reacts by also SLIDING in the same direction (Think of those five steel balls hanging on strings and you lift one then drop it...equal force is applied to the ball on opposite side.) but quickly, the resistance vector will cause object to stop sliding and instead it will begin to ROLL. This then fully explains the wobble....contact of cue to object, the spin transfer vector is applied (for all practical purposes applied immediately while the object will ALWAYS begin by sliding and eventually (depending on how hard/soft it is struck) start rolling. NOW you perfectly understand the wobble...SPIN starts, at some point ROLL starts and spin ceases, roll continues but with our reference dot now in a new location.
In fact the effect is much more subtle as you explained in an earlier post which leads to the wobble. It appears that the object ball is 'turned' slightly and then continues in a forward roll. This would explain the motion of the measle to me and it would appear as you say that any transferred spin 'dies away' rapidly.

Again, I like your analogies and skill at explanation. Would I be wrong in questioning your assertion that there is a coefficient of friction in play at the instant of contact? It is only a question and I am not confident in this but if we view the balls as perfect spheres then the point of contact is just that - a point. In effect there is an infinitesimal point of contact and does a coefficient of friction apply in this non-planar situation? I have no doubt that there is effective friction due to the irregularity of the surfaces on a microscopic level but I wonder if it is actually calculable??
This is fantastic hypothesizing! I agree exactly with your theory. Real life doesn't quite work like that though. In mechanical engineering, you have properties called tensile strength and compression strength...basically, how much you can stretch or compress a material before it fails. But long before the failure occurs, there will be a surprising amount of distortion. Have you ever watched a slow motion video of a golf ball being struck? Obviously a golf ball is "softer" than a billiard ball but it is ridiculous how much the golf ball compresses when struck by the face of the club. The "contact area" you are referring to can be a circle about 3/4" in diameter! On slow mo video, the shape of the golf ball changes into a capital letter "D". Of course, billiard balls compress nowhere near that, but I recall someone smart doing some sort of calculation to try to figure this out and the answer he came up with is that the compression will cause a contact area of something like 1/8" diameter and the two billiard balls will remain in contact with each other for some certain number of microseconds. The details are not important....I plainly see that you will understand the concept.
p.s.- After re-reading my response, I will add one more sentence. Remember what I said about ivory billiard balls? This concept then can explain why the ivory never had kicks....even if coefficients of friction were identical (which is of course unlikely), if ivory as a material is far less compressible than the plastic phenolic resin (which I believe is a near certainty), then the contact surface of the ivory could be just tiny and thereby explain why excess friction would not transfer.


I am very interested that you raise the subject of kicks and I hesitate to raise any theories or questions when there have been much deeper studies than I could hope to achieve. However, it occurred to me earlier in the thread that if spin can be transferred then we should also consider top and backspin. Is it the case that a possible explanation for kicks might lie in the following (at least some kicks). I have not considered or seen this theory before but may be mistaken.
Bingo! (and I don't mean Stuart.) As for "deeper studies", I don't think anyone has conclusively proven anything about the cause of kicks yet. What I think has been done probably isn't much more than intensive versions of the video work by myself and Kevy, coupled with a lot of head scratching. So for the most part, all it seems we really have to go on is the anecdotal evidence. As for me, I have plenty of anecdotal evidence, both watching professionals on video and experience on my own table. It seems to me that there is no single cause of kicks other than to say that it is quite definitely excessive friction at those critical few microseconds mentioned above when cue and object are clung together. The sources of that excessive friction is what is at debate. Many say chalk dust, some have suggested static electricity, Shaun Murphy came out with some sort of oil in the cloth or something coupled with the table heaters. The fact is that ALL of these may be correct. Think about the heater thing for a second...if you are out on a cool, dry autumn day, you feel a little cold so you rub the palms of your hands together. But on a hot, summer day at the beach, if you rub your hot, sweaty palms together, the coefficient of friction is obviously different. Not the best analogy but it makes it easy to see that yes, temperature could conceivably play a role. Think about how the heaters actually work....they are little heating coils somehow embedded at certain locations in the slates, and the heat must then dissipate throughout the slates. (For the record, I have no idea how it actually works, but I don't think it is rocket science so I am making my best guess.) One would think there must be "hot spots" on the slate; areas warmer than others. Perhaps if a ball sits untouched and unmoving for a long period directly over a heating coil, it can conceivably absorb more heat and maybe have a higher coefficient of friction when it is finally struck later in the frame. Seems plausible and anecdotally, it does seem like quite a few kicks occur late in a frame at a critical juncture. No doubt in my mind that the vast majority of kicks do occur not from top spin, not bottom or side, but from plain ball striking. This is where the cue ball is very simply ROLLING when it contacts the object. Here is how I think of that....any sort of spin will apply a "glancing blow" contact with the surface of the object, absolute minimal contact. Plain ball on the other hand, the surfaces will remain in contact for the longest possible time, the compression mentioned above is at maximum so there is maximum contact surface area and the balls are in contact for the longest possible period (though still only microseconds). Have you noticed that kicks mainly seem to occur at lower speeds (longest contact time) and full or near full ball contact (largest contact surface, not a glancing blow) and also when the striker is pretty much just trying to do a minimal amount of positional movement...just straightforward rolling ahead a small amount (few kicks when applying lots of spin or moving White a long distance for position)?

So, if we play with top spin and spin is transferred then at the moment of contact the cue ball will attempt to impart backspin to the object ball - the gear effect. This opposes the forward momentum imparted by the linear motion of the cueball and to my mind would give rise to a likely reaction. I have not seen any empirical evidence as to whether most kicks occur when the cueball is given topspin but anecdotally I seem to recall it rarely occurring when screw is applied in which case the transferred spin would agree with the forwards momentum. I shall see what I can find on youtube.
Totally agree with this paragraph with just one thing to add. Again, I have anecdotal evidence that yes, top spin and bottom spin will definitely also transfer to the object as yet another force vector. Several years back, I re-leathered the pockets of my table. I thought it would be a good idea to double layer the leather over the steel rims to protect the ball surfaces. (The leather had worn through on one of the pockets previously and I just dealt with it with wads of tape for a period before the re-leathering. Unfortunately, the double layer has really resulted in a couple of the pockets being very "springy". One of the middle pockets in particular, shots played in a certain way have a very good chance of hitting leather, bouncing back against the lip of the pocket opening, then back to leather, and back out on the table surface. I have long since cut away some of the leather to loosen it up and it has surely stretched a bit over time, so the problem is not bad anymore, but still happens on occasion. When I was analyzing all this (I am pretty anal about these things, as if you didn't already know that), I discovered that I could very easily recreate the problem about 4 out of 5 attempts....hit it at a certain speed, from a certain angle, dead center of the pocket leather, and (drum roll please......) medium pace screw shot. All else the same but using center ball or top spin, no problem at all. Undoubtedly, the screw spin transfers to topspin on the object and that spin causes the critical reaction upon contact with the leather. ZERO doubt about it in my mind.

As always I would be interested in your thoughts as I think you have a very good understanding of the physics at play and a skill for explaining.

Thank you very much. I know I bore the hell out of most people and surely I can carry a concept to an extreme...it is just the way my brain works and over the years I have been able to successfully apply these specific types of knowledge (and to be clear, knowledge and skill are two entirely different things) to greatly improve my snooker.

Be sure to keep me updated regarding your project.