modifying the tangent line
- Thread starter berlowmj2
- Start date
With english, draw and follow. And speed.
Linda...I'm surprised at your comment. English (sidespin) has NO influence on tangent line, WITHOUT draw or follow...until the CB strikes a rail. Speed has no affect on tangent line either...unless there is draw or follow. A high speed stun shot merely travels down the tangent line until the CB strikes a rail...and then the CB comes off the rail at the same angle it went in at.
Scott Lee
www.poolknowledge.com
Scott Lee
www.poolknowledge.com
Joe Villalpando
Joe spends one of his DVD's explaining this and showing it in great detail. Both Linda and Scott have valid points. Draw and follow are the primary things affecting the tangent line. Speed makes them take effect sooner or later after hitting the object ball. Sidespin shouldn't have any effect on the tangent line before it hits the rail. However that isn't quite true because in reality we almost never shoot with a level cue. I can and do change the tangent line a little with a lot of sidespin on a slow shot. Dirty balls help for this as does high humidity, two things I often deal with.
I strongly recommend buying Joe's DVD because it gives you the exact nuts and bolts of how to control the cue ball off of the object ball.
Hu
Joe spends one of his DVD's explaining this and showing it in great detail. Both Linda and Scott have valid points. Draw and follow are the primary things affecting the tangent line. Speed makes them take effect sooner or later after hitting the object ball. Sidespin shouldn't have any effect on the tangent line before it hits the rail. However that isn't quite true because in reality we almost never shoot with a level cue. I can and do change the tangent line a little with a lot of sidespin on a slow shot. Dirty balls help for this as does high humidity, two things I often deal with.
I strongly recommend buying Joe's DVD because it gives you the exact nuts and bolts of how to control the cue ball off of the object ball.
Hu
The tangent line is the tangent line is the tangent line. It cannot be modified. You may modify your aiming point along the tangent line for
various reasons but the tangent line is an absolute.
My definition of a tangent line is; A plane shared by the CB and OB when , all other things being equal, it is perpendicular to a line drawn through the center of the CB, OB, and center of the target pocket
Flame time
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I suspect your point that the tangent line cannot be modified is correct, what can be modified is the cue ball path as it relates to the tangent line.
Follow and Draw can be used to modify the cue balls path as it relates to the tangent line.
As far as your definition of a tangent line, I have a hard time visualizing how the center of the pocket relates to the tangent line.
Follow and Draw can be used to modify the cue balls path as it relates to the tangent line.
As far as your definition of a tangent line, I have a hard time visualizing how the center of the pocket relates to the tangent line.
This is an extremely important concept to grasp for understanding how to move the CB. There is absolutely no influence on the tangent line by side spin directly.
Now I say directly because some folks get confused and misunderstand a subtle difference that occurs with applying sidespin. I've had to explained that to folks I've taught in the past. I'll make my feeble attempt to explain exactly what I mean and where I've seen the confusion come.
There are two objectives that get slightly confusing. 1. contacting the OB at the same specific and exact spot and 2. The ability of sidespin to influence the path of the OB.
Forgetting about pocketing an OB for a moment and talking simply about contacting an OB with the CB at the specific point "A". Given this exact same contact point on the OB you can apply any amount of left or right hand spin and the CB will come off the OB at the same angle regardless of the sidespin.
Now, where I've seen some folks get confused while attempting to pocket an OB. Folks will insist that in an effort to miss hitting another OB or in an effort to avoid a scratch they will apply english (sidespin we are talking here .. NOT TALKING FOLLOW OR DRAW) and they insist this side spin changes the path of the CB and avoids the unwanted kiss or scratch.
Well, yeah it does, but that's not cause the tangent line's diversion has been changed. It's because the side spin allows you to throw the OB, which in return allows you to CHANGE the spot on the OB you are contacting. When you hit the OB in a different place you get a different deflection ( a different tangent angle based on hitting the OB in a different place.)
Huh? The tangent line is of infinite length.
This too is an indirect result of a secondary reaction. The 90 degree tangent that the CB deflects from the OB is based on a center ball hit with the CB SLIDING as it hits the OB. ( the absence of draw or follow). All CBs initially come off the OB on the tangent line.The slower the CB is hit when follow or draw is applied the less time it spends sliding off the OB then it starts rolling forward or drawing backward and the tangent line decays to follow or draw. If that's what you mean. Conversely the harder you hit the CB the longer time it is spent sliding so the longer you see the CB slide along the tangent line.
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sidespin and the cue ball's path along the tangent line
OK, I see some folks want to split hairs. Knowing the OP isn't stupid, most of us assumed he was talking about the cue ball's path along the tangent line. Anyone that doubts that sidespin can affect the cue ball's path need only go to the store and buy two rubber balls of the same size and weight to increase the effect so that it is more visible. It would defy the laws of physics that some on here are so fond of for sidespin to have no effect at all.
The simple fact that it throws the object ball proves that it throws the cue ball also.
"For every action there is an equal and opposite reaction."
You do have to change your contact point because the object ball is thrown and because you get a slight masse effect because your cue isn't truly level you have to change your aim point slightly. I await anyone's explanation of how only one ball can be thrown in a collision.
Hu
OK, I see some folks want to split hairs. Knowing the OP isn't stupid, most of us assumed he was talking about the cue ball's path along the tangent line. Anyone that doubts that sidespin can affect the cue ball's path need only go to the store and buy two rubber balls of the same size and weight to increase the effect so that it is more visible. It would defy the laws of physics that some on here are so fond of for sidespin to have no effect at all.
The simple fact that it throws the object ball proves that it throws the cue ball also.
"For every action there is an equal and opposite reaction."
You do have to change your contact point because the object ball is thrown and because you get a slight masse effect because your cue isn't truly level you have to change your aim point slightly. I await anyone's explanation of how only one ball can be thrown in a collision.
Hu
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Maybe I should have said "no discernable difference" in the tangent line using side spin as opposed to a practical and useful difference using follow or draw.
I don't believe it is splitting hairs explaining the practical use of spin to direct the CB off the OB as opposed to it's usefulness off a rail since it is completely useless to use side spin to attempt to change the tangent line when hitting the OB in the same spot if you are not going to a rail with the CB unless (as I mentioned) it is your intent to change the contact point of your shot.
I don't believe it is splitting hairs explaining the practical use of spin to direct the CB off the OB as opposed to it's usefulness off a rail since it is completely useless to use side spin to attempt to change the tangent line when hitting the OB in the same spot if you are not going to a rail with the CB unless (as I mentioned) it is your intent to change the contact point of your shot.
True tangent line is cause/effect without follow or draw during contact of cue ball with object ball also, on a cut shot as you increase the speed of your cue ball the tangent line will change more/quicker the fuller you hit the ball you are cutting.
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Very astute observation. The line perpendicular to the tangent line only needs the two points ( center of CB and center of OB) to prove itself.
The target pocket is added only because we are, after all, playing pool.
(and it is consistent with the Ghost Ball , anti-aiming system.
)Actually I have to modify this by saying that the third point is needed on the perpendicular line because when the aiming point is changed to alter the direction of the cue ball after contact, the english applied forces the object ball back on to the line to the center of the pocket. AHA!
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Technically, the tangent line itself can be modified, but only by introducing the 3rd dimension (altitude). Assuming the line from the OB to the pocket can't be changed, there are actually many contact points on the OB that the CB can hit to send it there, and each contact point will define its own tangent line. Of these contact points, however, only one can be struck if we presuppose that the CB is on the bed of the table. Assume an airborne CB, though, and quite a variety of tangent lines can be achieved.
I admit, however, that this post is not constructive. The tangent lines that aren't coplanar with the bed of the table are effectively impossible to utilize with any acceptable measure of accuracy and control.
-Andrew
I admit, however, that this post is not constructive. The tangent lines that aren't coplanar with the bed of the table are effectively impossible to utilize with any acceptable measure of accuracy and control.
-Andrew
Maybeto create a I'm misunderstanding the question.
IMO the tangent line is defined by the line perpenticular to the line formed by the contact point of the two balls. That can't be changed. Only the contact point can be changed to create a different TL. Applying follow or draw will not change the line either. It will only change the path after the tangent is taken which must happen for ?some distance. Only speed differences can change the amount of distance the CB follows the TL before the follow or draw changes the CB path.
IMO the tangent line is defined by the line perpenticular to the line formed by the contact point of the two balls. That can't be changed. Only the contact point can be changed to create a different TL. Applying follow or draw will not change the line either. It will only change the path after the tangent is taken which must happen for ?some distance. Only speed differences can change the amount of distance the CB follows the TL before the follow or draw changes the CB path.
Right you are Tom...and with a slow rolling CB, the tangent will "run out" almost immediately...meaning that the CB will travel down the tangent line only a very short distance (perhaps < 1"). This is quite obvious with the 30 degree/rolling CB/peace sign concept.
Scott Lee
www.poolknowledge.com
Scott Lee
www.poolknowledge.com
Aha, Aha!
I can see this in my minds eye.
Sidespin does not alter the tangent line.
Changing the aiming point, by definition, does.
But sidespin forces the OB back on the original perpendicular line path to the pocket thus, instantaneously and in fact, reinstating the original tangent line.
-------------What fun!!!!!!
I can see this in my minds eye.
Sidespin does not alter the tangent line.
Changing the aiming point, by definition, does.
But sidespin forces the OB back on the original perpendicular line path to the pocket thus, instantaneously and in fact, reinstating the original tangent line.
-------------What fun!!!!!!