Cue Ball rotation after it hits OB

N

naji

AzB Silver Member
Silver Member
Hello all,
OB on the spot, i have CB about 3 diamonds away with about 30 degrees cut to RH pocket, i shot it with extreme draw 20 times, every time i made sure my tip is 100% center. With this cut i expect OB to have clockwise rotation and CB counterclockwise rotation, but noticed that CB has clockwise after it hits OB, and when deflected from side rail it seem to be killed.


I tried to shoot same spot shot, but the cut angel such that CB go horizontally to side rail to see where it goes after it hits it, to my surprise it spun to near the opposite side pocket

I shot same shots above with stun center CB hit hard, CB did not have much of a spin

So the question is does CB gets same rotation as object ball after a 20 degree or more cut with power draw, or is it the cloth is effecting this.

CB i have is the tournament type with red spots all over it


Thanks.


DR. Dave i searched your site did not find this info, maybe i missed it.,,,
 
I've explained this on here a number of times, but it has been pointed out to me that I am not a pro or a scientist, so what I say doesn't matter to anyone on here. Sorry, but you will have to ask a pro or a physicist.
 
It depends, but usually, yes, the CB and OB will often end up with side spin in the same direction after a cut. I believe the moving CB will pick up more spin from the pact than the stationary OB.

There are (at least) two ways that an OB can pick up spin.

One is from the direction of travel of the CB when it contacts the surface of the OB during a cut. As you mentioned, this will tend to spin the OB slightly clockwise (for a cut to the right).

The second is from spin on the CB. Counterclockwise CB spin will tend to induce clockwise spin on the OB. In your case, I understand that you didn't have any spin on the CB.

With no added side spin, the CB will tend to pick up clockwise spin from a cut to the right.

When there are spin-inducing conditions that are opposing, they work against each other, and if equal, will result in no resulting side spin. This is one of the major tenets of CJ's TOI strategy. If the correct amount of inside spin (right on the CB if cutting to the right) is applied to the CB, there will be no CB side spin after the impact.

Other factors that affect the amount of induced CB and OB spin include the speed at which the shot is hit, the cleanliness of the ball surfaces, and possibly even humidity and the condition of the cloth.

I think you would find my slow motion videos to be very helpful in visualizing the transfer and induction of spin between CB and OB. Visit
www.youtube.com/SloMoHolic
To see the videos. Currently, there are four long videos relating to pool and one very short one.

I may not be using the correct terminology in this response, but I believe the concepts are correct.

I hope this helps!

-Blake
 
Neil said:
I've explained this on here a number of times, but it has been pointed out to me that I am not a pro or a scientist, so what I say doesn't matter to anyone on here. Sorry, but you will have to ask a pro or a physicist.
Click to expand...

Sorry, Neil, pros only. Physicists know nothing of such things.

I did miss your explanations before, though. Maybe you could PM it to me if you don't want to post it here?
 
SloMoHolic said:
It depends, but usually, yes, the CB and OB will often end up with side spin in the same direction after a cut. I believe the moving CB will pick up more spin from the pact than the stationary OB.

There are (at least) two ways that an OB can pick up spin.

One is from the direction of travel of the CB when it contacts the surface of the OB during a cut. As you mentioned, this will tend to spin the OB slightly clockwise (for a cut to the right).

The second is from spin on the CB. Counterclockwise CB spin will tend to induce clockwise spin on the OB. In your case, I understand that you didn't have any spin on the CB.

With no added side spin, the CB will tend to pick up clockwise spin from a cut to the right.

When there are spin-inducing conditions that are opposing, they work against each other, and if equal, will result in no resulting side spin. This is one of the major tenets of CJ's TOI strategy. If the correct amount of inside spin (right on the CB if cutting to the right) is applied to the CB, there will be no CB side spin after the impact.

Other factors that affect the amount of induced CB and OB spin include the speed at which the shot is hit, the cleanliness of the ball surfaces, and possibly even humidity and the condition of the cloth.

I think you would find my slow motion videos to be very helpful in visualizing the transfer and induction of spin between CB and OB. Visit
www.youtube.com/SloMoHolic
To see the videos. Currently, there are four long videos relating to pool and one very short one.

I may not be using the correct terminology in this response, but I believe the concepts are correct.

I hope this helps!

-Blake
Click to expand...


That is great stuff thanks much SloMoHolic.. I will check your youtube
 
SloMoHolic said:
Other factors that affect the amount of induced CB and OB spin include the speed at which the shot is hit, the cleanliness of the ball surfaces, and possibly even humidity and the condition of the cloth.
Click to expand...

I'd like to add that I don't believe these other factors affect the spin induction in a linear manner.

For example, for a 30 degree cut to the right: a very slow shot will generate some side spin on the CB. A medium speed shot will generate more side spin. But a hard shot may not generate ANY side spin on the CB. This has something to do with the starting friction vs the sliding friction between the two ball surfaces. Perhaps one of our experts will illuminate us with the details.

Again, this is based on my observations, so it may not be 100% correct, but seems to be accurate enough for me. :)

-Blake
 
Neil said:
I've explained this on here a number of times, but it has been pointed out to me that I am not a pro or a scientist, so what I say doesn't matter to anyone on here. Sorry, but you will have to ask a pro or a physicist.
Click to expand...

In the contrary i like your posts, we agree and disagree to the best of our ability (experience) to judge the situation until we collectively reach so high that both of our results are the same. No giving up..
 
If I may reply to my own reply,

One thing I find helpful in visualizing this is to imagine the following:

You are walking down the hall, and someone is standing in your way, facing you. You try to walk to your left to avoid running into them, but you accidentally bump your right shoulder against their right shoulder. Both of you will "pick up" some left (clockwise) "spin."

I hope that makes sense.

-Blake
 
SloMoHolic said:
I'd like to add that I don't believe these other factors affect the spin induction in a linear manner.

For example, for a 30 degree cut to the right: a very slow shot will generate some side spin on the CB. A medium speed shot will generate more side spin. But a hard shot may not generate ANY side spin on the CB. This has something to do with the starting friction vs the sliding friction between the two ball surfaces. Perhaps one of our experts will illuminate us with the details.

Again, this is based on my observations, so it may not be 100% correct, but seems to be accurate enough for me. :)

-Blake
Click to expand...

I believe the speed of the shot also matters because a softer shot will pick up a "forward" roll before contact where a harder shot will be "skidding" across the table at the time of impact. Obviously on a more technical level, this is where varying amounts of friction come into play.
 
SloMoHolic said:
I'd like to add that I don't believe these other factors affect the spin induction in a linear manner.

For example, for a 30 degree cut to the right: a very slow shot will generate some side spin on the CB. A medium speed shot will generate more side spin. But a hard shot may not generate ANY side spin on the CB. This has something to do with the starting friction vs the sliding friction between the two ball surfaces. Perhaps one of our experts will illuminate us with the details.

Again, this is based on my observations, so it may not be 100% correct, but seems to be accurate enough for me. :)

-Blake
Click to expand...

i will polish my balls set, CB, and clean my cloth and try, i think balls cleanness, and CB clean surface, not rough, is huge factor.. Thanks again.
 
Mr. naji,

IMHO It's rather difficult to discuss the exact spin a CB will have after a collision when different englishes are being use as it is dependent on the combination of so many factors & to what degrees of each.

But consider the collision factor like this. When a 'stunned' sliding cue ball with no spin contacts a stationary object ball also with no spin the contact points will tend to rebound away from each other.

In other words the inside of the cue ball will be slowed while the outside of the cue ball continues & the outside of the object ball will be pushed.

The way I look at it is that the cue ball will pick up a bit of outside spin while the object ball will pick up a bit of the same kind of 'spin' as though it were hit with inside spin on the cue ball.

This is what the bit of spin from CJ's TOI can reduce or negate & why the cue ball seems to 'float' & rebound off a rail with no running spin picked up from the collision or it might even have some hold spin on it.

I hope I said that correctly & it helps you in how you think of it.

Best Regards to You &
 
Neil said:
I've explained this on here a number of times, but it has been pointed out to me that I am not a pro or a scientist, so what I say doesn't matter to anyone on here. Sorry, but you will have to ask a pro or a physicist.
Click to expand...

Feelin sorry for yoursef today?
1302668450450_4400261.png
 
Black-Balled said:
Feelin sorry for yoursef today?
1302668450450_4400261.png
Click to expand...

Not at all, I pm'ed Naji and explained it to him. Not speaking of you, but just tired of casting pearls to swine, if you know what I mean. The forum consensus made it clear that they only want to hear from pros on how to do things, so, I will do my part to "help" them.:D
 
SloMoHolic said:
If I may reply to my own reply,

One thing I find helpful in visualizing this is to imagine the following:

You are walking down the hall, and someone is standing in your way, facing you. You try to walk to your left to avoid running into them, but you accidentally bump your right shoulder against their right shoulder. Both of you will "pick up" some left (clockwise) "spin."

I hope that makes sense.

-Blake
Click to expand...

That was a great example!!!
 
Neil said:
Not at all, I pm'ed Naji and explained it to him. Not speaking of you, but just tired of casting pearls to swine, if you know what I mean. The forum consensus made it clear that they only want to hear from pros on how to do things, so, I will do my part to "help" them.:D
Click to expand...

While you may not ever be made aware of it...you have had some valuable input in the past.

You might stumble upon one again, unless you quit.;)
 
ENGLISH! said:
Mr. naji,

IMHO It's rather difficult to discuss the exact spin a CB will have after a collision when different englishes are being use as it is dependent on the combination of so many factors & to what degrees of each.

But consider the collision factor like this. When a 'stunned' sliding cue ball with no spin contacts a stationary object ball also with no spin the contact points will tend to rebound away from each other.

In other words the inside of the cue ball will be slowed while the outside of the cue ball continues & the outside of the object ball will be pushed.

The way I look at it is that the cue ball will pick up a bit of outside spin while the object ball will pick up a bit of the same kind of 'spin' as though it were hit with inside spin on the cue ball.

This is what the bit of spin from CJ's TOI can reduce or negate & why the cue ball seems to 'float' & rebound off a rail with no running spin picked up from the collision or it might even have some hold spin on it.

I hope I said that correctly & it helps you in how you think of it.

Best Regards to You &
Click to expand...

Thanks Rick..

Just to be clear or in agreement, if i hit CB with center stun and OB that has a cut angle, CB will get opposite english of that of OB after contact.
If CB is spinning backward and contacts an OB the CB backward spin will convert to backward/side spin with same rotation as OB after contact
If we put top english i expect CB to have same rotation as OB after contact!

Based on the above to counter effect the rotation we apply a touch of opposite spin on CB
 
One ball transfers spin to another by rubbing sideways on its surface. That rub can be from either the motion or the spin of the first ball. If the rub gives clockwise spin (left english) to the second ball, the first ball has to get an equal amount of clockwise spin. If the first ball starts with spin before the collision, then the final spin will be the total of what it came in with and what was acquired during the collision.

Which side spin is added to each ball does not depend on whether you have draw or follow on the cue ball.

The same side of spin on the two balls if you start with none is due to the force sideways at the contact point being in opposite directions on the two balls but on opposite "sides" of the two balls.

It's a little confusing that if you want to get right spin on the object ball by spinning the cue ball you need to use left english on the cue ball. The trick is that during the collision some of the spin on the cue ball is used up in making the object ball spin so the cue ball is getting net right english.
 
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