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SPetty
03-30-2004, 04:36 PM
I hope I can phrase this right... and I totally hope it's not too stupid of a question...

All else being equal, does follow or draw affect the final angle of the object ball off the cue ball at all?

Eric.
03-30-2004, 04:48 PM
<blockquote><font class="small">Quote SPetty:</font><hr> I hope I can phrase this right... and I totally hope it's not too stupid of a question...

All else being equal, does follow or draw affect the final angle of the object ball off the cue ball at all?
<hr /></blockquote>

Hi SPetty,

I hope I'm understanding the question...

I don't have the scientific answer but what I usually do on cut shots with force follow is to cut in a smidge fatter and no compensation on draw/cut shots. I dont know if it's my stroke or swerve/squirt/snap/crackle or pop, but it seems to work for me. If I dont compensate (very tiny bit) on force follw cut shots, I will overcut the OB.

HTH


Eric

Rod
03-30-2004, 05:20 PM
Well those physics guys may come up with a doozie. LOL You'd never know the difference if in fact there is any at all. Now if it has side and draw you have squirt, swerve, and all that happy stuff. Cue angle plays a roll also. Top and side has squirt but no swerve, depending on cue elevation and bridge height once again.

I'm assuming you just wanted the simple answer in the second sentence.

Rod

SpiderMan
03-30-2004, 05:24 PM
Susan,

Strangely enough, my own observations seem to be the opposite of Eric's. When I cut with draw, I deliberately fade the hit a little fatter to avoid overcutting.

SpiderMan

Ken
03-30-2004, 06:06 PM
About 45 years ago I was told that draw will increase the cut somewhat and follow will decrease it. Now we have a bunch of physics experts who will oppose virtually everything that was accepted 45 years ago. I really don't know the answer but I think the effect is similar to outside and inside english (ignoring swerve and squirt) but considerably less. I'm sure the modern gurus will claim I am totally wrong.
Ken in CT

tateuts
03-30-2004, 06:18 PM
<blockquote><font class="small">Quote SPetty:</font><hr> I hope I can phrase this right... and I totally hope it's not too stupid of a question...

All else being equal, does follow or draw affect the final angle of the object ball off the cue ball at all?
<hr /></blockquote>

I aim on the same line with any center axis hit. Because of friction, I think both draw and follow can reduce the "throw effect" on fuller ball hits, but I don't think it's enough to adjust for.

If I am concerned about sticky balls or humid conditions, I will use a little spin to counter the throw effect.

Chris

phil in sofla
03-30-2004, 06:40 PM
If the balls are somewhat sticky, and/or the hit is soft, a center ball hit may occasion some 'cling' on the ball, pushing the object ball forward of the line a little before it begins to roll along a parallel line to the actual line of aim. This would tend to make the line the object ball takes equivalent to a slight undercutting of the ball, compared to the intended line.

Using either center top or center bottom on the cue ball helps eliminate the frictional cling of the hit, and thereby minimizes any push of the ball ahead of the line, and makes for a line of the object ball closer to the actual line of aim.

How significant this is will vary, depending on the stickiness of the balls, the speed of the hit, and the thinness or fullness of the contact.

The same 'truer' line, by eliminating contact throw, is achievable by using outside or inside English, although those have their own issues (possible deflection at the initial hit, possible throw upon contact).

As to force follow shots requiring a slightly FULLER hit, I suspect that is because when the cue ball is given that kind of extreme action, it is likely airborne, and thus contacting the object ball not on its fattest point, at the equator of the ball, but higher, which WOULD make for a thinner hit (thus requiring an adjustment of aiming fuller).

Barbara
03-30-2004, 06:54 PM
Oooooo.... I can't wait til the board experts respond to this one!! Good Q!

As I have always read/understood, given a full ball hit, draw on the cue ball will impart follow spin onthe object ball. And follow on the cue ball will impart draw on the object ball.

And as I have always thought, draw makes a ball come off at a wider angle on a rail and follow tightens the angle.

So I really need to read the answers to this Q.

Bob Jewett?? You out there???

Barbara~~~nails banks with feel, or what?

bigbro6060
03-30-2004, 10:39 PM
my advice is f**k the physics and get out on the table and try sh*t out /ccboard/images/graemlins/grin.gif

KGeeED
03-31-2004, 08:51 AM
<blockquote><font class="small">Quote bigbro6060:</font><hr> my advice is f**k the physics and get out on the table and try sh*t out /ccboard/images/graemlins/grin.gif <hr /></blockquote>

I just watched a tape by Don Feeney about this and at the end of the tape I was amazed that I could make a ball at all.

I came to the same conclusion. Don't think about all of the BS. Practice and make the damn shot.

Fred Agnir
03-31-2004, 08:58 AM
<blockquote><font class="small">Quote SPetty:</font><hr> I hope I can phrase this right... and I totally hope it's not too stupid of a question...

All else being equal, does follow or draw affect the final angle of the object ball off the cue ball at all?
<hr /></blockquote>I think if the cueball is actually spinning when it contacts the object ball, then there is less cut-induced throw compared to if the cueball is not spinning. So, the answer is , "yes."

The one case where I think it might confuse people is when you hit a drag draw shot where the cloth rubs the spin off. By the time you actually make contact with the object ball, the actually collision is a stun shot, which has the most cut-induced throw.

IMO, of course,

Fred

PEEKAY1
03-31-2004, 06:22 PM
The velocity and trajectory of your cue determines the angle bywhich the object ball travels. The contact point between objects is unchanged when on a level field. If you shoot higher than the plain, or lower, you will affect its true angle. That's just a hi-tech way of saying maybe. <font color="blue"> </font color>

Ralph S.
03-31-2004, 08:17 PM
Yes, absoluteley there is an effect on the angle object ball takes after contact. Speed, spin, ball cleanliness, etc. all have some type of impact on what angle the ball will take.

Rod
03-31-2004, 08:23 PM
<blockquote><font class="small">Quote SPetty:</font><hr>

All else being equal
<hr /></blockquote>

Ha Ha Ha SPetty, don't you just like people that pay attention. /ccboard/images/graemlins/laugh.gif Did you get your answer?

Rod

Alfie
03-31-2004, 08:55 PM
<blockquote><font class="small">Quote SPetty:</font><hr> All else being equal, does follow or draw affect the final angle of the object ball off the cue ball at all? <hr /></blockquote>Hi, Steve. Go to the well, imo.

http://groups.google.com/groups?q=follow+draw+affect+cut+angle+group:rec.sp ort.billiard+author:shepard

daviddjmp
04-01-2004, 12:02 PM
I think that dead-center draw and follow affect the path of the cueball after contact far more than the path of the object ball. There is always some level of collsion-induced throw involved which decreases as the cut becomes thinner. I don't know how this throw is affected by top or bottom spin on the cueball.

SPetty
04-02-2004, 11:08 AM
<blockquote><font class="small">Quote Rod:</font><hr> Did you get your answer?<hr /></blockquote>Well, yes, no, maybe, I don't know! /ccboard/images/graemlins/smile.gif

Thanks for all the responses. Looks like there's not a "general consensus" about this question.

The impetus behind the question is that I seem to be able to aim and pocket balls a little more accurately using a draw shot than I can using a follow shot. Something about me using follow to pocket the ball sometimes causes it to rattle the pocket.

There is something different (hence the "all else being equal" part) that happens. If I could rule out physics, then it's obviously in the execution. If the physics could explain it, then I could learn to understand it.

Sid_Vicious
04-02-2004, 11:34 AM
I haven't followed this thread, I actually get into an over alanysis mode when I try to get the physics answers to "why", so I play and develop through mistakes. I do know that when I have those full table thin cuts to the corners that I need to draw, sort of like I'm going for a kick instead of the cut, and more balls roll in than when I center hit or try any follow. "How do I do that?" Well I just found it through being in the trenches, and I forgot about the details of what was happening with the spin. I might be wrong but I can't think that many of the daily hustlers dwell upon all this rotational, up and down english reactions, except for the finished results after playing a lot over the years. Lot's of players do, I know one very well, I just can't seem to find the brain cells and a balance of emotional trust to keep my stroke together while disecting the game at this level...sid

Wally_in_Cincy
04-02-2004, 12:51 PM
<blockquote><font class="small">Quote SPetty:</font><hr>
...I seem to be able to aim and pocket balls a little more accurately using a draw shot than I can using a follow shot. Something about me using follow to pocket the ball sometimes causes it to rattle the pocket.... <hr /></blockquote>

perhaps cueing high creates an unwanted masse effect as it does when you bridge over a ball.

spidey says on a draw shot he cuts the ball a bit fatter. this would seem to buttress the "more spin = less cling/throw" theory. BTW i agree w/ spidey

daviddjmp
04-02-2004, 12:57 PM
I like to use follow on long thin cuts, no english. I find that draw seems to give me a thicker hit as well-

SPetty
04-02-2004, 03:15 PM
<blockquote><font class="small">Quote Wally_in_Cincy:</font><hr>perhaps cueing high creates an unwanted masse effect as it does when you bridge over a ball.

spidey says on a draw shot he cuts the ball a bit fatter.<hr /></blockquote>perhaps, but with my stroke, cueing high levels out the cue - that is, I raise the tip of the cue, not the entire cue, thereby leveling the cue more.

To interpret what Spidey said for me - since I feel I'm aiming properly with the draw - is to cut a bit thinner for the follow shot.

And this, probably, is one of the differences (okay, problems) that I have with *aiming*; i.e. "you" hit it fatter for for draw shots while I hit it thinner for follow shots. "Same thing" yet different. But the net affect is that "you" pocket many more balls that I do. /ccboard/images/graemlins/crazy.gif

Fred Agnir
04-02-2004, 03:34 PM
<blockquote><font class="small">Quote SPetty:</font><hr> <blockquote><font class="small">Quote Wally_in_Cincy:</font><hr>perhaps cueing high creates an unwanted masse effect as it does when you bridge over a ball.

spidey says on a draw shot he cuts the ball a bit fatter.<hr /></blockquote>perhaps, but with my stroke, cueing high levels out the cue - that is, I raise the tip of the cue, not the entire cue, thereby leveling the cue more.

To interpret what Spidey said for me - since I feel I'm aiming properly with the draw - is to cut a bit thinner for the follow shot.

And this, probably, is one of the differences (okay, problems) that I have with *aiming*; i.e. "you" hit it fatter for for draw shots while I hit it thinner for follow shots. "Same thing" yet different. But the net affect is that "you" pocket many more balls that I do. /ccboard/images/graemlins/crazy.gif
<hr /></blockquote>I think my post covers these two ideas.

Fred

Rod
04-02-2004, 04:07 PM
Well lets talk about execution. People have the tendency to execute certain shots better with follow and some with draw.They have a way to shoot shots that makes them feel more comfortable, ie cinch a shot. Of course all will tell you what they feel works best for them and believe it is the top or bottom english that causes the effect. They also may have certain little moves they make given what type of stroke is used. I believe this factor is much more important than a minute little difference, if any, whether top or bottom is used.

To try to simplify the game itself, to make a ball the aim line should be center pocket. That gives us a margin for error since the pocket can be hit right or left side and still go in. Of course as any ball gets closer to a rail then the aim is even more critical. I'd be much more concerned with side english or stroke execution than I ever would be with whether top or draw had some dinky effect. Lets not bring in rocket science just yet! /ccboard/images/graemlins/laugh.gif

I think the bottom line is stay away from any english unless it's necessary for position, and not the belief it will cinch a shot. That and if you feel you hit the ball fat or thin with either top or bottom, then practice that weakness. You didn't say where the ball hit using top, you just said it rattled the pocket. If I were you I'd make it a point to know what side of the pocket the ball hit when it didn't fall. You need that feedback to make any corrections. Keep the game simple, our minds get enough clutter just from normal everyday living.

Rod

Ross
04-02-2004, 05:00 PM
Susan - as Fred said, the physics answer is that topspin or backspin at contact tends to reduce the friction between the balls. Less friction means less less contact-induced throw, so the object ball cuts a bit sharper for the same hit. Another way to think of it is that the top or backspin allows you to hit the ob closer to the "geometrically-lined-up-to-the-pocket-ghostball" point (you don't have to allow for throw so much).

Also a harder hit reduces throw. When you use bottom you probably tend to hit the cb ball harder (since the backspin will slow the cueball down during its travels) and so you get less throw and a truer departure angle for the ob. When you use top you probably tended to hit the cb softer and the increased throw due to the softer hit can make you bobble the ball.

If you watch the pros shooting the 9 ball on a simple cut shot, they seem to favor using a bit of draw on these shots when possible. I imagine experience has shown them that this helps them to cinch the shot more consistently.

And I find on the table that a bit of draw does help me slightly to cinch moderate cut angle shots.

SPetty
04-02-2004, 10:03 PM
<blockquote><font class="small">Quote Fred Agnir:</font><hr> I think my post covers these two ideas.<hr /></blockquote>Yessir. Thank you. I agree. I listened the first time. I always listen to you, Fred. I think in a very like manner. That "logical" thing, you know. /ccboard/images/graemlins/smile.gif

SPetty
04-02-2004, 10:11 PM
<blockquote><font class="small">Quote Rod:</font><hr> Well lets talk about execution. <hr /></blockquote>Thanks, Rod. Great advice.

SPetty
04-02-2004, 10:17 PM
<blockquote><font class="small">Quote Ross:</font><hr> ...the physics answer is that topspin or backspin at contact tends to reduce the friction between the balls.

When you use bottom you probably tend to hit the cb ball harder (since the backspin will slow the cueball down during its travels) and so you get less throw and a truer departure angle for the ob. When you use top you probably tended to hit the cb softer and the increased throw due to the softer hit can make you bobble the ball.<hr /></blockquote>Thanks, Ross. You might be onto something there!

BeanDiesel
04-03-2004, 12:58 AM
why dont you ask this guy.
http://www.engr.colostate.edu/~dga/pool/dr_dave.html

Fred Agnir
04-03-2004, 06:46 AM
<blockquote><font class="small">Quote BeanDiesel:</font><hr> why dont you ask this guy.
http://www.engr.colostate.edu/~dga/pool/dr_dave.html <hr /></blockquote>Better yet, ask him to become a CCBoard member!

bluewolf
04-03-2004, 08:21 AM
[quote=Rod I'd be much more concerned with side english or stroke execution than I ever would be with whether top or draw had some dinky effect. Lets not bring in rocket science just yet! /ccboard/images/graemlins/laugh.gif

I think the bottom line is stay away from any english unless it's necessary for position, and not the belief it will cinch a shot. That and if you feel you hit the ball fat or thin with either top or bottom, then practice that weakness. You didn't say where the ball hit using top, you just said it rattled the pocket. If I were you I'd make it a point to know what side of the pocket the ball hit when it didn't fall. You need that feedback to make any corrections. Keep the game simple, our minds get enough clutter just from normal everyday living.

Rod <hr /></blockquote>

Thanks Rod. I have missed shots due to side spin so do like you say, do not use it unless I need it to create an angle off of the rail. never noticed a difference on the ob though with top or bottom though, again, just how it reacts off the rail, follows or draws for position on the next shot and how it, the cb, acts off the tangent line.

I just figure if I miss a shot, it is usually that I did not line it up corrcectly(or did something funky in my stroke since it is good, not perfect) or is lack of experience, so have confidence that things will get better with time and practice. /ccboard/images/graemlins/crazy.gif

Laura---&gt; have quite enuff to fill this head with, just need to play

SPetty
04-04-2004, 07:48 PM
<blockquote><font class="small">Quote Fred Agnir:</font><hr> Better yet, ask him to become a CCBoard member! <hr /></blockquote>I did; he responded:

Thanks for the offer... I wish I had time to respond to all of the message there and try to clear things up, but I already put too much time into my pool and billiards work with my book, website, and monthly magazine articles. If I didn't have a full-time job at the university, I would do more, but there is only so much time in a day. Hopefully, people can find some answers in my existing and future work.

Good luck with your game,
Dr. Dave

dr_dave
12-01-2004, 03:27 PM
SPetty,

I apologize for my past reluctance to participate in the BD CCB. At the time, I was way over committed. I've recently created a thread entitled Dr. Dave's "Illustrated Principles" articles Q&amp;A (http://www.billiardsdigest.com/ccboard/showthreaded.php?Cat=&amp;Board=ccb&amp;Number=167746&amp;page =0&amp;view=collapsed&amp;sb=5&amp;o=&amp;fpart=1), where I plan to become a more active participant in the forum.

It looks like Ross did a good job of answering your "cue ball spin cut shot" physics question. I also intend to look at this question some more. I'll let you know if I come up with any additional insight.

Fred Agnir
12-01-2004, 05:01 PM
<blockquote><font class="small">Quote dr_dave:</font><hr> SPetty,

I apologize for my past reluctance to participate in the BD CCB. At the time, I was way over committed. I've recently = <hr /></blockquote>

<blockquote><font class="small">Quote Dr. Dave:</font><hr>I wish I had time to respond to all of the message there and try to clear things up<hr /></blockquote> I hope you understand Dave that forums such as these are also an opporunity for things to be cleared for you as opposed to by you.

Fred &lt;~~~ ain't one to clear up $hit.

Deeman2
12-02-2004, 08:36 AM
<blockquote><font class="small">Quote SPetty:</font><hr> I seem to be able to aim and pocket balls a little more accurately using a draw shot than I can using a follow shot. Something about me using follow to pocket the ball sometimes causes it to rattle the pocket.

<font color="blue"> Spetty,

I know this is an older thread but I missed it before. I think the truth on over and undercutting with high and low are probably secondary with most players to "sighting". From your above statement, I would guess that you mis-hit cut shots with high more often, perhaps, because it is more difficult for most folks to hit the exact center of the cueball (left/right) using high english/spin simply because the sight picture is a little more obscured than when you are hitting it low where you have a more unobstructed view of the entire cue ball. Just food for thought. </font color>

Deeman
<hr /></blockquote>

SpiderMan
12-02-2004, 09:27 AM
<blockquote><font class="small">Quote Deeman2:</font><hr> <blockquote><font class="small">Quote SPetty:</font><hr> I seem to be able to aim and pocket balls a little more accurately using a draw shot than I can using a follow shot. Something about me using follow to pocket the ball sometimes causes it to rattle the pocket.

<font color="blue"> Spetty,

I know this is an older thread but I missed it before. I think the truth on over and undercutting with high and low are probably secondary with most players to "sighting". From your above statement, I would guess that you mis-hit cut shots with high more often, perhaps, because it is more difficult for most folks to hit the exact center of the cueball (left/right) using high english/spin simply because the sight picture is a little more obscured than when you are hitting it low where you have a more unobstructed view of the entire cue ball. Just food for thought. </font color>

Deeman
<hr /></blockquote> <hr /></blockquote>

Deeman,

I'll furthermore expound - I think it's easier to "center up" on the cueball when sighting with low because the vertical centerline runs right through the point where the ball touches the table. If you're aiming with low, you have this "touch point" to guide you to the center.

Several years ago I played Jeremy Jones in a Texas Express tour stop down in Austin (he won), and I noticed that he initially addressed all his shots with his tip aimed low on the cueball. This was regardless of whether he actually played it with top, bottom, or center. I asked him about it after our match, and he just said that it was "easier to line up that way".

SpiderMan

Chopstick
12-02-2004, 02:12 PM
<blockquote><font class="small">Quote SpiderMan:</font><hr>

Several years ago I played Jeremy Jones in a Texas Express tour stop down in Austin (he won), and I noticed that he initially addressed all his shots with his tip aimed low on the cueball. This was regardless of whether he actually played it with top, bottom, or center. I asked him about it after our match, and he just said that it was "easier to line up that way".

SpiderMan <hr /></blockquote>

Steve Mizerak and Jerry Brock did the same thing for the same reason.

Don Feeny demonstrates the effects of draw and follow on aiming and object ball behavior in his video "Problems with Cue Ball and Object Ball Behavior." I would reccomend this tape to anyone. I liked it.

Basically what it boils down to is all cloth has some nap to it. The fuzzier it is the more pronounced the effect. When a ball comes to rest it will settle into the fuzz some. It will also come to rest in the lowest spot it can.

Draw will tend to lift the object ball and get into a natural roll quicker than follow. It has the same effect as the loft on a putter. Follow will tend to drive the object ball lower and cause the cue ball and object ball to stick together longer. Most people learn to compensate in their aiming for these effects.

Don Feeny does a good job of explaining and demonstrating them. The video quality is poor so some of them are hard to see. I have never seen anyone who could produce effects like skid at will like he can.

DavidMorris
12-02-2004, 02:54 PM
<blockquote><font class="small">Quote SpiderMan:</font><hr>Several years ago I played Jeremy Jones in a Texas Express tour stop down in Austin (he won), and I noticed that he initially addressed all his shots with his tip aimed low on the cueball. This was regardless of whether he actually played it with top, bottom, or center. I asked him about it after our match, and he just said that it was "easier to line up that way".<hr /></blockquote>
I believe Bustamante does the same. When I watch him play, his practice strokes make it look like he's hitting nearly every shot with draw -- each practice stroke ends almost on the table. On his final swing he moves the cuetip to the desired position. Seems hard to do and would be more prone to error for me than sighting high up on the CB, but he makes it look easy. /ccboard/images/graemlins/smile.gif

pooltchr
12-03-2004, 05:49 AM
<blockquote><font class="small">Quote Chopstick:</font><hr>

Draw will tend to lift the object ball and get into a natural roll quicker than follow. <hr /></blockquote>

How can this be? Since draw products back spin which is the exact opposite of the "natural roll", the ball has to wait for the effects of gravity and friction to take effect and allow the forward (natural) roll to begin. Place a striped ball with the stripe going across the ball at 90 degrees from the stroke angle. Hit it with draw and you can see how it rolls with backspin, then transitions to a slide or skid before the natural roll begins. Top spin would seem more likely to get into the natural roll more quickly.
JMHO
Steve

SpiderMan
12-03-2004, 07:38 AM
<blockquote><font class="small">Quote pooltchr:</font><hr> <blockquote><font class="small">Quote Chopstick:</font><hr>

Draw will tend to lift the object ball and get into a natural roll quicker than follow. <hr /></blockquote>

How can this be? Since draw products back spin which is the exact opposite of the "natural roll", the ball has to wait for the effects of gravity and friction to take effect and allow the forward (natural) roll to begin. Place a striped ball with the stripe going across the ball at 90 degrees from the stroke angle. Hit it with draw and you can see how it rolls with backspin, then transitions to a slide or skid before the natural roll begins. Top spin would seem more likely to get into the natural roll more quickly.
JMHO
Steve <hr /></blockquote>

Steve,

He's saying that draw on the cueball gets the object ball into natural roll more quickly, which is correct. That's why you must play this 8-ball shot with draw whenever the distance between the balls is too short for the 8 to achieve substantial unassisted forward roll prior to contacting the 1:

START(
%Ar5D1%BL8P7%CJ7O4%DL8N2%EM7P1%FK7P1%GK7N8%Ho1F8%I L7O4%JK8M6
%KJ7P7%LJ7N3%MK7Q3%NJ7Q9%OJ7M0%Pk4I8%Wn8G2%Xk4I8%Y t2B8%Zr7C8
%[t0C1%\o4F5
)END

SpiderMan

SPetty
12-03-2004, 11:37 AM
<blockquote><font class="small">Quote Chopstick:</font><hr> Draw will tend to lift the object ball and get into a natural roll quicker than follow. Follow will tend to drive the object ball lower and cause the cue ball and object ball to stick together longer. <hr /></blockquote>Hi Chopstick,

I think this is the answer to the original question. All else being equal, this would make the slight difference that I see when I'm shooting these shots. Thanks for taking the time to answser.

PoolFool
12-03-2004, 04:42 PM
I'm surprised you are still having trouble with high hits.
That anti-deflection device I gave you should have eliminated the problem. Just remember, when using top english, just move it up on your shaft about 1/2 inch.

PoolFool

Rod
12-03-2004, 05:33 PM
Still looking for that secret? I still stick by my original answer.

You never did say if you were prone to miss one direction or another. That is using top left or right and from which side of the table?. Do you make all with low left or right? If not, which direction do you miss?

Really no answer is required just looking for a pattern. Now what you may or may not know, unless your shooting slow, top or bottom doesn't mean didley. This is just to minute. Now, don't tell me you miss all slow shots. LOL The answer isn't there, it's not your miss.

Exception, a push or slide. Now you'd know if that happened, you can see it.

Rod

SPetty
12-03-2004, 06:31 PM
<blockquote><font class="small">Quote Rod:</font><hr> Still looking for that secret? <hr /></blockquote>Actually, no. I didn't bring this thread back up from long ago.

The answer I got was that there didn't seem to be an answer. What I saw when I went back to the table didn't seem to jive with what a few others said. When I believe I'm shooting the exact same shot at the exact same aiming point at the exact same speed, with the only difference that I know of being whether I'm hitting high with follow or low with draw (no left or right), the shot hit with the follow doesn't cut as much. Whether left or right, the cut angle is "flatter" for me, which seemed to be in contradiction to what a few others posted.

The original purpose of my post was not "what am I doing wrong and how do I fix it?" - it was "is there a physical reason that might explain this behavior?"

pooltchr
12-03-2004, 08:35 PM
OOPS! My Bad. I read it wrong and thought he was talking about the natural roll of the cb. /ccboard/images/graemlins/blush.gif
Chalk another one up to old age!!! /ccboard/images/graemlins/grin.gif
Steve

Qtec
12-03-2004, 11:20 PM
[ QUOTE ]
that is, I raise the tip of the cue, not the entire cue, thereby leveling the cue more.
<hr /></blockquote>

This could be the problem. Most people who do this tend to miss the pocket, on this shot, at side A.



START(
%AN5G7%BL7P8%CJ5O4%DL7N1%EM7P1%FK6P1%GK6N8%HM7N8%I L7O4%JK6M5
%KJ5P7%LJ5N2%MK6Q4%NJ5R0%OJ5M0%P^1S2%QA6E2%WC1C5%X M9G3%YD5F1
%ZM0G7%]P2I0%^]2R5
)END

wei (http://endeavor.med.nyu.edu/~wei/pool/pooltable2.html)





Qtec

Stretch
12-04-2004, 09:57 AM
<blockquote><font class="small">Quote Rod:</font><hr> Still looking for that secret? I still stick by my original answer.

You never did say if you were prone to miss one direction or another. That is using top left or right and from which side of the table?. Do you make all with low left or right? If not, which direction do you miss?

Really no answer is required just looking for a pattern. Now what you may or may not know, unless your shooting slow, top or bottom doesn't mean didley. This is just to minute. Now, don't tell me you miss all slow shots. LOL The answer isn't there, it's not your miss.

Exception, a push or slide. Now you'd know if that happened, you can see it.

Rod <hr /></blockquote>

Hi Rod. I thought this might be a good thread to bring this up. Isn't it true that by useing a high cueing position when useing follow that your actualy exerting a downward force on the cue ball on impact? If that's the case, then what will happen is a slight masse effect. This might account for a lot of those misses when useing "hard" follow. Some of this effect can be reduced by raising the bridge hand and keeping the cue as level as possible but it can't be negated entirely. On the other hand by hitting low on the cue ball you can actually lift the cb off the table (the secret of long draw shots, by skimming the ball down table a lot of the backspin will not wear off) SO conversly hard follow will dig into the cloth. I don't know if this is pertinent to the jist of this thread, just something to concider is all. St~~a lot better with your smooooth stroke thought /ccboard/images/graemlins/wink.gif~~

Ross
12-04-2004, 10:10 AM
<blockquote><font class="small">Quote SPetty:</font><hr>
The answer I got was that there didn't seem to be an answer. What I saw when I went back to the table didn't seem to jive with what a few others said. When I believe I'm shooting the exact same shot at the exact same aiming point at the exact same speed, with the only difference that I know of being whether I'm hitting high with follow or low with draw (no left or right), the shot hit with the follow doesn't cut as much. Whether left or right, the cut angle is "flatter" for me, which seemed to be in contradiction to what a few others posted.
...
<hr /></blockquote>

Actually, Spetty you were given two physical explanations that DID fit what you were observing. I pointed out that when shooting a cut shot with draw you likely hit the cb quite a bit firmer than when using follow. There are 2 reasons for this: 1. you have to to keep the backspin on the cb as it is sliding across the felt, and 2. cut shots with follow tend to be hit relatively slowly since the cb will naturally roll a long ways under this condition. And (I believe this has been shown to be true) greater shot speed leads to less contact-induced throw (CIT), so the ob cuts more sharply.

Remember how Eric said he tended to overcut when using follow for HARD shots? Straight pool players also report that they tend to overcut their breakout shots when they hit them very firmly. All of this data fits the greater speed = less throw explanation as well.

Spetty, to test this theory, you could try your cut shot experiment again. This time shoot your draw shots as softly as you can while still keeping draw on the cb at contact. Then shoot the same shot with follow but very firmly. See if you still tend to undercut the follow shots.

You were also given Feeney's explanation that fit your observations: when a cb with follow contacts an ob the friction forces the ob slightly into the felt (sort of a squeeze effect) and and also puts a little draw on the ob. All of this leads to either more friction or a longer contact time between the balls, resulting in more CIT. Conversely, when the cb has draw, the friction tends to lift the ob from the felt and to quickly put follow on the ob, and there is a slightly less friction or contact time, and hence less throw.

And I think your overall observations are correct. If you watch pros cinching the 9 they usually use a bit of draw, not follow, when they have a choice. This also allows them to shoot the ball with a more firm, confident shot.

Rod
12-04-2004, 02:08 PM
There is lots of answers in most of the posts. It's putting it all together. The basis of testing anything is consistant set up and execution.

All you can do is use the best examples from each test. I'll just tell you though when there is a large difference, it's execution. So you have to narrow it down to very close misses. Once you zero in on those, then you might be able to define a usable answer.

Let me reiterate though, those close misses are only effected at slower speeds. That is all being equal as stated in your first post. If you believe the flatter angle is caused by using top then allow for that in aim. By doing that you should consistantly pocket the ball. Now if you start overcutting the ball or just miss either direction it's another matter, isn't it?

Rod

Rod
12-04-2004, 05:46 PM
<blockquote><font class="small">Quote Stretch:</font><hr> <blockquote><font class="small">Quote Rod:</font><hr> Still looking for that secret? I still stick by my original answer.

You never did say if you were prone to miss one direction or another. That is using top left or right and from which side of the table?. Do you make all with low left or right? If not, which direction do you miss?

Really no answer is required just looking for a pattern. Now what you may or may not know, unless your shooting slow, top or bottom doesn't mean didley. This is just to minute. Now, don't tell me you miss all slow shots. LOL The answer isn't there, it's not your miss.

Exception, a push or slide. Now you'd know if that happened, you can see it.

Rod <hr /></blockquote>

Hi Rod. I thought this might be a good thread to bring this up. Isn't it true that by useing a high cueing position when useing follow that your actualy exerting a downward force on the cue ball on impact?

<font color="blue">I suppose Stretch but it's marginal at best. You'd have to view it like squirt but in a vertical direction. If you hit a ball soft the result is very little squirt. I'm not saying it doesn't exist but I am saying it shouldn't be considered a real factor.
That's the reason we aim center pocket is to make up for small discrepancies.</font color>

If that's the case, then what will happen is a slight masse effect. This might account for a lot of those misses when useing "hard" follow.

<font color="blue">I doubt that since it's a forward motion with very very slight downward force. Even then it's not what I'd call a real factor. The cue would need some elevation to make any signifiant difference. I'd always question the execution over what I'd call dinky effects. I mean you have to look at someone play. Are they making most shots? Are they missing other shots not even related to this issue? How's the fundamentals? In the end someone making most shots really isn't concerned about such a small issue. Well being inquisitive, no problem but I wouldn't want to lead someone down the wrong path where other things are much more important</font color>

Some of this effect can be reduced by raising the bridge hand and keeping the cue as level as possible but it can't be negated entirely. On the other hand by hitting low on the cue ball you can actually lift the cb off the table (the secret of long draw shots, by skimming the ball down table a lot of the backspin will not wear off) SO conversly hard follow will dig into the cloth.

<font color="blue">I assure you it isn't digging into the cloth. Follow or draw at firm speeds don't spend all that much time on the table. Granted draw is in the air more. Cue angle and speed is what determines length of time on the bed. In most cases I'm concerned with stroke angle, stroke speed and stroke direction. The faults here will out weigh this issue 99 to 1. My opinion of course. LOL

I don't want to get lengthy but I shoot delayed draw and follow shots. Both are determined by speed and cue angle. Delayed means the c/b does not react immediately as in normal follow or draw shots.</font color>

I don't know if this is pertinent to the jist of this thread, just something to concider is all. St~~a lot better with your smooooth stroke thought /ccboard/images/graemlins/wink.gif~~ <hr /></blockquote>


I think it's all pertinent to some, at some time, in their playing capacity.

Rod

Stretch
12-04-2004, 08:46 PM
<blockquote><font class="small">Quote Rod:</font><hr> There is lots of answers in most of the posts. It's putting it all together. The basis of testing anything is consistant set up and execution.

All you can do is use the best examples from each test. I'll just tell you though when there is a large difference, it's execution. So you have to narrow it down to very close misses. Once you zero in on those, then you might be able to define a usable answer.

Let me reiterate though, those close misses are only effected at slower speeds. That is all being equal as stated in your first post. If you believe the flatter angle is caused by using top then allow for that in aim. By doing that you should consistantly pocket the ball. Now if you start overcutting the ball or just miss either direction it's another matter, isn't it?

Rod <hr /></blockquote>

Thanks Rod. You have a great knack for putting things in perspective. St.

One
12-13-2004, 04:44 PM
There is a non visible difference.

Vertical and horizontal spin have the same amount of throw. But with draw the object ball doesn't lift up from the table because of gravity. And follow makes the object ball get pressed down on the cloth.

So draw on the cueball gives the object ball less resistance on the cloth for a small amount of time. And follow gives the object ball more resistance on the cloth.

The angle the object ball takes gets different because of this.

If you use follow on the cueball the object ball will skid a few mm after the collision. And it will also get pressed down into the cloth. It is like a slight massť. The object ball gets pressed down into the cloth and it will always have sidespin on it when hitting the object ball from an angle. The thicker the cloth is, the more the object ball gets pressed down, and the more massť effect.

The nap of the cloth matters the most, the more sidespin on the ball, the more you see it. Not only snooker cloths have a nap, all cloths have it, but it is less visible.

The more vertical spin you have on the cueball when contacting the object ball, the less collision induced throw you will get on the object ball. But it doesn't eliminate it completely.

If you hit the object ball exactly straight on, then follow or draw doesn't affect the angle of the object ball. Because you don't get any sidespin on the object ball.

Bob_Jewett
12-13-2004, 08:02 PM
Quoting One...
&gt; ... Vertical and horizontal spin have the same amount of throw.

I believe this to be false. The mechanism that causes throw is horizontal friction of the surface of the cue ball on the object ball, and that is reduced for both follow and draw shots. This is explained in more detail in Ron Shepard's paper on pool physics.

&gt; So draw on the cueball gives the object ball less
&gt; resistance on the cloth for a small amount of time.
&gt; And follow gives the object ball more resistance on the cloth.

I think this effect is negligible, and in any case will not affect the angle of the cut as there is no sideways component.

&gt; The angle the object ball takes gets different because of this.

I think that statement is false.

&gt; If you use follow on the cueball the object ball will
&gt; skid a few mm after the collision.

On all shots the object ball does not start rolling smoothly on the cloth for quite a distance -- sometime more than four diamonds of travel for fast shots. It is easy to show this. That distance will be slightly increased or decreased by follow or draw on the cue ball, but not significantly.

&gt; And it will also get pressed down into the cloth.
&gt; It is like a slight massť.

If you're saying that the object ball will curve, I think you're wrong.


&gt; The nap of the cloth matters the most, the more
&gt; sidespin on the ball, the more you see it.

I believe that the nap of the cloth has no effect on how much throw there is.

One
12-13-2004, 11:26 PM
<blockquote><font class="small">Quote Bob_Jewett:</font><hr>
&gt; The nap of the cloth matters the most, the more
&gt; sidespin on the ball, the more you see it.

I believe that the nap of the cloth has no effect on how much throw there is. <hr /></blockquote>
I meant sidespin on the object ball.

One
12-13-2004, 11:39 PM
<blockquote><font class="small">Quote Bob_Jewett:</font><hr>
&gt; And it will also get pressed down into the cloth.
&gt; It is like a slight massť.

If you're saying that the object ball will curve, I think you're wrong.


&gt; <hr /></blockquote>
It is the same as when you hit the object ball higher than centre on the vertical axis with the cueball.

The cueball jumps and hits the upper part of the object ball which makes the object ball get pressed down on the cloth and bounche up. When the object ball drops on the table the sidespin makes it curves sideways.

Follow on the cueball is the same and makes the object ball get pressed down in the cloth. The object ball will bounche up but will still be touching the cloth but it will have less resistance from it. So after the object ball returns to "normal" cloth resistance the sidespin will take effect and make it curve.

You can't see this with a high speed camera.

One
12-13-2004, 11:58 PM
<blockquote><font class="small">Quote Bob_Jewett:</font><hr> &gt; If you use follow on the cueball the object ball will
&gt; skid a few mm after the collision.

On all shots the object ball does not start rolling smoothly on the cloth for quite a distance -- sometime more than four diamonds of travel for fast shots. It is easy to show this. That distance will be slightly increased or decreased by follow or draw on the cue ball, but not significantly.
<hr /></blockquote>
I made mistake, it is few cm, not mm.

The amount of backspin the object ball gets depends on the speed and spin on the contact with the object ball. With lag speed (5 km/h) and max top spin, the object ball will skid half a diamond. With 30 km/h and max top spin the object ball will skid 3 diamonds.

With draw the object ball will not skid but will immediately start transferring to rolling naturally.

One
12-14-2004, 12:25 AM
<blockquote><font class="small">Quote Bob_Jewett:</font><hr> Quoting One...
&gt; ... Vertical and horizontal spin have the same amount of throw.

I believe this to be false. The mechanism that causes throw is horizontal friction of the surface of the cue ball on the object ball, and that is reduced for both follow and draw shots. This is explained in more detail in Ron Shepard's paper on pool physics.
<hr /></blockquote>
Vertical axis spin decreasing collision induced throw is not what I meant. I mean hitting the object ball straight on. If you remove the table you get the same amount of throw with vertical and horizontal spin, assuming you use the same amount of spin and speed.