PDA

View Full Version : Forcing the Angle

LBBill
01-07-2005, 09:43 PM
Another phenomenon and known fact to top players is if you are cutting a ball into a pocket, lets say your shooting the 9-ball as a spot shot into the r/h corner pocket, as you increase your cue ball speed, whether it's forward speed or spin speed or both and you are, (hitting the exact same spot on the object ball) the object ball will cut more. Now if the balls are extremely dirty this effect is almost impossible, but with new cloth, especially simonis, this effect is increased, but, as the cloth gets dirty and wears out, this action is decreased. Making adjustments in this area, is what all good/great players are constantly doing and seeing while playing a match.

GeraldG
01-08-2005, 06:51 AM
My guess is that this would be due to the fact that the cueball will try to sort of "drag" the object ball along with it (on the cueball path) to a certain extent. The longer the cueball is in contact with the object ball the further if "drags" the object ball. The faster the cueball is moving, the less time it is in contact with the object ball, so the less distance the object ball is dragged. So, in reality what you get from more speed is actually an object ball departure angle that is closer to the actual line through the contact points to the pocket. The dirtier the balls are, the more the cueball is going to "drag" the object ball because there will be more friction between them. I don't think it's possible to make the ball travel on a line that is a more acute angle than that line through the center of the balls to the pocket at the point of contact.

I think you can actually get much the same effect by just using a little outside english so the cueball "rolls" off the object ball more, rather than dragging it. Which technique you would want to use would depend entirely upon where you wanted the cueball to end up after the shot. The more speed you use, the more you have to turn loose of the cueball.

jjinfla
01-08-2005, 07:37 AM
The harder you hit the CB the less throw you induce on the OB. I think someone once said that here. Not Mike Sigel though.

Jake

randyg
01-08-2005, 07:40 AM
Do you think Mike Sigel was wrong??????SPF-randyg

Qtec
01-08-2005, 02:09 PM
If I have a half-ball spot shot, can you tell me how much throw I am going to get- if any?

Qtec

jjinfla
01-08-2005, 04:44 PM
RandyG and Qtec,

I would never presume to tell, or think, that Mike Sigel is wrong about anything concerning pool. The only thing dummer than that is to accept someone's proposition bet.

It was a tongue and cheek remark to Mike's article where he stated there was no such thing as throw.

Ray Martin says there is throw.

Buddy Hall says there is throw.

I guess it all depends on what one means by throw.

I know, you guys are trying to confuse me more than I am already.

I wonder if Mike was pulling everyone's leg?

Jake

tateuts
01-08-2005, 09:47 PM
<blockquote><font class="small">Quote LBBill:</font><hr> Another phenomenon and known fact to top players is if you are cutting a ball into a pocket, lets say your shooting the 9-ball as a spot shot into the r/h corner pocket, as you increase your cue ball speed, whether it's forward speed or spin speed or both and you are, (hitting the exact same spot on the object ball) the object ball will cut more. <hr /></blockquote>

That explains why I miss the nine ball so much - thanks!

Chris

Bob_Jewett
01-10-2005, 03:46 PM
<blockquote><font class="small">Quote Qtec:</font><hr> If I have a half-ball spot shot, can you tell me how much throw I am going to get- if any? <hr /></blockquote>
There is a table of throw versus cut angle and speed of shot in Capelle's "Play Your Best Pool." The data that are shown there first appeared in a Billiards Digest article in June 1995. A plot that was in the article is available as: http://www.sfbilliards.com/throw.gif

To answer your question, for that kind of ball (cleanliness, age, etc.) the throw for a 30-degree cut with no spin involved was between 3.5 and 6 degrees. That's a lot of throw, but I did not repeat the experiment with other (cleaner, newer) balls. Theory says there will be less throw with follow or draw on the cue ball.

It's easy enough to set up your own experiment with combinations played at different speeds.

paulfr
01-15-2005, 05:47 AM
I think everyone may have missed what LBBill is saying.
LBBill said the cut will increase with CB speed.
He did not say throw will decrease. That is one interpretation for what is seen. But another is that the OB takes off inside the line of centers not less outside the line of centers (throw).
Here is an article on the issue called Object Ball Deflection .....
http://www.easypooltutor.com/article239.html

My take on this is that if it can be shown that an OB will
go/deflect INSIDE the CB-OB line of centers then the explanation could be either ..
1/ A hard hit CB leaves the table and if it is off the table only a fraction when it hits the OB, the reduced diameters will cause an overcut. (Explanation on this another time).
2/ If the balls are very smooth and clean, they slide just a fraction before the friction takes hold and this causes the cut angle to increase.
3/ Both of the above.

What I would love to see is an experiment that can prove the phenomena exists and a way to measure just how much an OB can deflect in degrees. Even 2 degrees from 5 diamonds or more would be very significant.
Longer shots require much greater accuracy. But maybe many of us miss them not because of accuracy, but because of failing to account for OB Deflection ???

mksmith713
01-15-2005, 11:14 AM
Clean balls have alot to do with the amount of throw as well.
What some players don't realize is that though balls look and feel very smooth to the touch, they actually have pores.
If you were to look at pool balls under a microscope, you'd notice them very clearly.
The pores have a certain coeffeicent of friction.
These pores combined with spin on the cue ball are what causes throw.
The dirtier the balls (pores filled with chalk, dirt,etc.), the less friction created.
If the balls were truly smooth, there would be no throw.
The same phenomenon as with bowling balls, except bowling balls are engineered with varying degrees of porousness to meet players wants and needs.

SpiderMan
01-17-2005, 07:43 AM
A fourth possibility could be that if the cueball is not sliding, ie has backspin or forward roll, the contact point is struck with either an upward or downward component of motion, not just an impact parallel to the table. Could this be a masse effect? If so, then I believe backspin might cause over cutting and topspin the opposite. If it's just due to an airborne cueball (your #1 postulate), then the result would be over-cutting regardless of whether it's shot with draw or follow.

BTW, the article you quoted does mention "hard draw" in the overcut example, but the author fails to make any connection. He seems to think it's just a result of shooting hard.

SpiderMan

SpiderMan

dr_dave
01-18-2005, 08:47 AM
<blockquote><font class="small">Quote Bob_Jewett:</font><hr> <blockquote><font class="small">Quote Qtec:</font><hr> If I have a half-ball spot shot, can you tell me how much throw I am going to get- if any? <hr /></blockquote>
There is a table of throw versus cut angle and speed of shot in Capelle's "Play Your Best Pool." The data that are shown there first appeared in a Billiards Digest article in June 1995. A plot that was in the article is available as: http://www.sfbilliards.com/throw.gif
<hr /></blockquote>
For people who have the book and want to see the data, it is on page 40.

Bob, great plot! Is the article also available online?

Phil also presents data for English deflection (squirt) on pages 92-93. This topic was hotly contested on this forum in another thread (http://).