FYI, you might find the info at the following links interesting (and maybe even revealing):
Regards,
Dave
The Stroke Thread
- Thread starter justnum
- Start date
Regards,
Dave
In today's world statistics from 50 years ago has been reduced to owning a spreadsheet program. The same should be said for billiards and physics concepts but it isn't. BCEC is an attempt, does it need work most likely, does it contain ideas from sophisticated math courses yes, will it be easy for people to understand, currently it seem not likely.
The tip bounces off the ball before your stroke can make any difference. Come up with a way around that unsophisticated fact.
pj
chgo
The video is interesting thanks for posting. The shooter in the video lassos the tip and jerks it back at the end of the stroke a bit that does not help with a clean shot.
So what do you think you are showing is there actually a different acceleration pattern and cause the cue ball to do something different after being stroked. I do not think the cue ball remembers how it is was hit beyond the following items.
Velocity, rotation rate and path/direction.
When you hit the ball the key points are the following.
Tip direction, contact location on the CB, speed of stroke at impact.
Beyond that I think better players have more power and control of the cue so the tip stays on path better through the moment of impact and the power keeps the tip speed going through impact. To illuminate let me give the following comparison think weaker players are like a Yugo barreling a long 68 mph and when it gets hit with a strong head wind (the cue ball) the car slows down significantly perhaps veers off path to some degree. The stronger player is like a Vette cruising at 68 gets hit with a head wind the driver does not even notice it and moves on thru to their destination.
I do not think you can hit the CB with a different stroke and alter the time you stay on the CB. I think if you work on all of your fundamentals that time may be improved (from .0008 sec to maybe .00085 sec) perhaps as you move from Yugo to Vette status. So I do not think much time should be spent in trying to be on the ball for longer. I think pool is a control thing and I think most players cannot control their tip location or speed and that is the cause of their lack of ability to be repeatable. So if you want players to play better get them working on hitting the cue ball in a consistent location and with consistent speed.
So what do you think you are showing is there actually a different acceleration pattern and cause the cue ball to do something different after being stroked. I do not think the cue ball remembers how it is was hit beyond the following items.
Velocity, rotation rate and path/direction.
When you hit the ball the key points are the following.
Tip direction, contact location on the CB, speed of stroke at impact.
Beyond that I think better players have more power and control of the cue so the tip stays on path better through the moment of impact and the power keeps the tip speed going through impact. To illuminate let me give the following comparison think weaker players are like a Yugo barreling a long 68 mph and when it gets hit with a strong head wind (the cue ball) the car slows down significantly perhaps veers off path to some degree. The stronger player is like a Vette cruising at 68 gets hit with a head wind the driver does not even notice it and moves on thru to their destination.
I do not think you can hit the CB with a different stroke and alter the time you stay on the CB. I think if you work on all of your fundamentals that time may be improved (from .0008 sec to maybe .00085 sec) perhaps as you move from Yugo to Vette status. So I do not think much time should be spent in trying to be on the ball for longer. I think pool is a control thing and I think most players cannot control their tip location or speed and that is the cause of their lack of ability to be repeatable. So if you want players to play better get them working on hitting the cue ball in a consistent location and with consistent speed.
Last edited:
Read the definition of what an instantaneous rate of change is. The same reason a radar gun tells traffic enforcement the speed a car is going is the same idea that can tell you how a stroke can influence the CB.
Instead of just think speed and velocity consider torsion and inertia. I'd love to stay away from the technical lingo but they are the language of the science. The fact that the tip "bounces" is referred to as a collision and in order for contact to happen the CS must touch the CB.
What a player can do during the contact of if they have the ability to control how the contact happens is the necessary idea to think of using stroke to influence the CB action.
In short instantaneous rates of change are what I am discussing, a simple way of saying that is consider the moment that contact begins, the duration of contact and the moment contact ends, yes those are very narrow margins of time, but they exist.
I'll post some vids later. Right now I am working on something else. But I guess the proof is in the video. Why bother talking?
Is pretty much nothing. Unless you're going to tell us how to make stroke changes during 1/1000 of a second contact time.
Why, indeed?
pj
chgo
First of all, your stroke must always be the same. It must be accelerating and smooth, with a nice follow-through. The spin is derived from the tip. To be more precise, the tip, when contacts the CB, compresses. If your stroke is moving straight forward smoothly accelerating, the compression of the tip is bigger as it contacts the CB for a longer period of time. Take a ball, put your index finger and push the ball lightly with it while maintaining the same velocity with the finger. You will see that the ball will very soon stop making contact with your finger and roll forward freely. If you make the same thing, but with an accelerating motion, your finger will always remain in contact with the ball. Now imagine doing this with your cue (accelerating and pushing forward aka follow through). If you have a nice accelerating motion, the time where the tip is contacting the CB and is compressed against it is greatly increased. Therefore, more "spinning energy" is passed to the CB. The softer the tip, the more it compresses, so the more it can spin the ball. (note that by spin, I mean english and draw and follow)
This stuff is easier to say than actually do them. Good cues and tips can be bought, but they are no stores where they sell a good stroke. The weight of the cue must do all the work when cueing, You will see many inexperienced players grabbing the cue with their thumb and their index, or by grabbing the cue with more fingers, but with their grip wide open. (fingers not "closed" enough) These are approaches of the principle that you must always grip your cue lightly in order to let its weight do all the work. You will not see many pros doing that but you will notice that their grip seems pretty solid and not loose. They grip the cue firmly and steadily but lightly at the same time. It is a difficult thing to describe actually, but you will find that by gripping the cue with a solid grip (do not put strength on your fingers, just close them together while lightly touching the cue), your aim and cueing will get more stable and less error-prone and if you manage to do this while playing with the weight of the cue (like throwing it forward) you will achieve good action on the cue ball. You will see that many times if you play a fast shot (not strong, there is no such thing as a strong shot, only a fast one, as the velocity and acceleration are the only things that matter when cueing) your hand will slip and the cue will move forward a bit. This is completely normal and it is a strong weapon in your arsenal. I try to always have this stuff in my mind when I am cueing. You will have to learn things on your own and find out what is suitable for YOUR GAME. Pool in many aspects is a matter of personal preference. Do not take any of the things I say (or anyone if he is not an instructor) for granted but consider them. If you think that your technique works, keep it. But try other things too. Do they help? Does it help if I press my finger more? Does it help if my arm makes a bigger arc? Etc. etc. Through trial and error you will find your way.
Of course there are many players who have an unorthodox way of gripping the cue. Bustamante has an ugly grip but this grip has "terminated" lots of players.
So. The draw shot. Your stroke must be the same. If it is draw, follow, stun or whatever. If you have a straight in shot and want to freeze the CB then you can do this with an infinite type of ways. You can put very little bottom spin and play fast, or cue with the tip almost touching the felt (danger of miscue) and play really slow. This is also called a drag shot, or a kill shot. You will hear the (beautiful) sound of the draw, see the CB rotate back like crazy, but with the very little velocity, the CB will arrive at the OB without any spin and freeze.
If you want to draw the CB at a straight line, you will do it if your fundamentals are correct and your cue is moving straight. You will just have to be cool, relax, do a nice follow through with lots of bottom english and if your aim is true and not cheat the pocket at all, your CB will roll back at the same line like it has a string attached on it.
This "side draw" you are saying is achieved if the CB and OB are not aligned with the pocket, or when you cheat the pocket intentionally or not. You can set a straight in shot and try to shoot the OB at the left or right side of the pocket with a stun shot. A stun shot is achieved with a spinless CB. You can do it by executing a stop shot but with the cheating of the pocket, the two balls collide off center and the CB will travel along the tangent line. If the CB arrives fast and spinless it will travel a longer distance. Therefore if you want to cover a long distance here, play a fast shot with not so much bottom spin. This can be done with every shot. Every OB has one and only a tangent line which the CB can travel on regardless of the initial position of the CB.
The greatest achievement in this game is having a good and beautiful stroke. All the other stuff will come and find you, as long as you play often and focused, if you have a good stroke (aim, position etc.). But the stroke...is something that you will have to find on your own. And of course you will be changing it throughout your entire playing life. Listen to every opinion and find out what's good for you. Good luck.
What level of mastery do you have in math and physics, I'll try to cater the video to the abilities of the audience. But I need to know what my audience knows.
Also terms are different some refer to spin and stroke or english, which terms are you comfy with?
What do you know?
Just a friendly observation here. If this is where you are directing your energy, your pool game is not going to show much improvement.
No offense intended, just a comment you might want to consider.
Steve
Could a softer cue tip result in a longer contact time? What about different cues? Is the acceleration through the cueball always an insignificant factor?
Switching to Christian Slater's most sarcastic voice...
No, contact time is completely instantaneous. Since the speed of light has a speed, then instantaneous contact time must be faster than the speed of light. We have now completely overturned physics.
A greek philosopher said to his student to walk into the ocean if he wanted to know how deep it is. Same applies here.
No, contact time is completely instantaneous. Since the speed of light has a speed, then instantaneous contact time must be faster than the speed of light. We have now completely overturned physics.
A greek philosopher said to his student to walk into the ocean if he wanted to know how deep it is. Same applies here.
The Issues
Points we all agree on:
1. The CB is hit by the CS.
2. The CS accelerates or hits the CB with an initial force and direction.
3. The CB spins when it is hit by the CS or after it hits an OB.
(CS = Cue stick, CB = cue ball, OB = object ball)
Points that are an issue:
1. What interaction does the CS have with the CB during a stroke?
2. Can the stroke be controlled so that the interaction with the CB is pre-determined?
3. Is there a theoretical stroke that can strike the CB such that BCEC between CS and CB exists?
(BCEC = beginning contact and ending contact)
These are the issues that I will discuss.
Points we all agree on:
1. The CB is hit by the CS.
2. The CS accelerates or hits the CB with an initial force and direction.
3. The CB spins when it is hit by the CS or after it hits an OB.
(CS = Cue stick, CB = cue ball, OB = object ball)
Points that are an issue:
1. What interaction does the CS have with the CB during a stroke?
2. Can the stroke be controlled so that the interaction with the CB is pre-determined?
3. Is there a theoretical stroke that can strike the CB such that BCEC between CS and CB exists?
(BCEC = beginning contact and ending contact)
These are the issues that I will discuss.
Yes. Hitting with sidespin also extends contact time. But not enough to make a controlled difference in the outcome in either case.
Because the stick is effectively stopped by ("bounces off") the cue ball when it makes contact and doesn't regain speed until after the cue ball is gone, there's no such thing as "acceleration through the cueball".
pj
chgo
I know you're tapdancing.
Post your video analysis and we'll let you know if it's over our heads (or yours).
pj
chgo
I already have multiple videos posted and enough experience to know to ask what material you have been prepared with before I begin my discussion.
Please humble me with your extensive knowledge about the physics of billiards in a brief paragraph to help me get a sense of who I am speaking to.
More tapdancing.
Now you're posting just for me? Post at the level of physics sophistication you think can be generally understood here. If you don't think anything you have to say can be generally understood here, maybe you're in the wrong forum for this topic...?
pj
chgo
I've elaborated on some ideas already. It is easy to take a counter position because all I have to do is make my argument for someone to oppose it.
But I am interested in the audience and your ideas specifically on the topic.
Don't by shy I am not quick to attack personal character only assumptions and conclusions.
I know I authored the thread but I insist you speak up more about your own views, perhaps they may help me create a more interesting article specific to your curiosities.
There is no hurry, this is not an assignment with a deadline.
So then what JimmyWhite said in his first paragraph is actually wrong.
Switching to Grampa McCoy's "daaaag-nabit!" voice...
I agree. But as people attempt to accelerate through the cueball they can still feel resistance to their muscular action, caused by the fact that the cue is still there and has mass, so that even after the cueball is gone they believe they are influencing the cueball. Add to this that the speed of sound is not that fast, their brains are telling them that the contact is still going on. However my sarcastic post has to do with the fact that people propel cues at objects and the way in which they propel that partially compressible tip at the ball can be variable. That does not mean that they are somehow doing some secret maneuver DURING the contact time. It means that I believe not all contact times are the same. I have no experiments to prove this. We are probably not going to change many minds here about that, daaaag-nabit!
I agree. But as people attempt to accelerate through the cueball they can still feel resistance to their muscular action, caused by the fact that the cue is still there and has mass, so that even after the cueball is gone they believe they are influencing the cueball. Add to this that the speed of sound is not that fast, their brains are telling them that the contact is still going on. However my sarcastic post has to do with the fact that people propel cues at objects and the way in which they propel that partially compressible tip at the ball can be variable. That does not mean that they are somehow doing some secret maneuver DURING the contact time. It means that I believe not all contact times are the same. I have no experiments to prove this. We are probably not going to change many minds here about that, daaaag-nabit!