Question about intentional swerve

Originally Posted by Tennesseejoe View Post
With a level cue, will the cue ball curve more with a 4:30 or a 1:30 hit?



Can you tape that stroke please? I'd like to learn this one.
I would have guessed 4:30. Maybe I'm confused with the question.

I will try later today. It might be a perception thing and I'm wrong, but when I shoot with english "off the rail", which of course forces a very high hit on the CB, the CB swerves at least a half ball.

If I shoot the same shot with a normal bridge on the table, and less high on the CB, the aim to pocket the ball for me is dramatically differnt.
 
...elevation isn't always necessary. I regularly swerve a full ball width with a level stroke shooting full length of a 10' table. And I mean easily. Its very easy to over do it too.
It's not possible to curve the CB without some vertical force (to create spin about a horizontal axis), but a truly level stroke is impossible unless the butt of your cue is not over a rail, so that probably explains your experience.

...if the obstruction is reasonably close, I might choose to hop the over the it rather than curve the CB.
Maybe that's just showing my inexperience.
That's a good choice IMO. A small straight hop is more accurate than a curve.

pj
chgo
 
It's not possible to curve the CB without some vertical force (to create spin about a horizontal axis), but a truly level stroke is impossible unless the butt of your cue is not over a rail, so that probably explains your experience.
pj
chgo

OK you got me there. The cue is not perfectly level. But I still contend with as level as possible and #4 hit one the CB meaning max possible back spin and side spin plus good speed control the ball will swerve pretty darn well.

Remember this is a 3C table, the CB is traveling approx. 8' before ball 2 and speed to bring the CB back to the original end of the table, like the corner. Actually its a possible 4 rail backup Short Long Long Short. or S L L Ball 3

I'm not arguing that an elevated cue caused more or sooner curve swerve.
https://www.youtube.com/watch?v=W-aewcf8WKU
 
What tip position on the CB creates the most intentional swerve?

Occassionally I find myself in the position where a "blocking" ball is between the CB and the OB by just a couple of milimeters. So all I need to do is swerve around the intervening ball a little bit.

Gut feel tells me to jack up at about a 30-degree angle and strike down on the CB (not like a trickshot masse, but maybe a 30-degree angle). But I've also had some success with swerves when I hit low on the CB.

If we ignore position for the next ball (let's say the next ball is a hanger that I can make from anywhere on the table), what tip position on the CB creates the most intentional swerve?

Or, it would also be instructive to know what tip position on the CB creates the most reliable swerve? (although that's probably more subjective due to the shooter's stroke).

Any tips you have to offer about intentional swerving is appreciated.

The cb will squirt as long as it is sliding. Once it stops sliding, it will then swerve.
 
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OK you got me there. The cue is not perfectly level.
lol - was only trying to "get you" on the same page.

But I still contend with as level as possible and #4 hit one the CB meaning max possible back spin and side spin plus good speed control the ball will swerve pretty darn well.
Of course, hitting with maximum back spin means you're hitting as downward as possible for that butt position... just sayin'.

pj
chgo
 
If you have a perfectly level cue stick (end rail removed), and striking the CB above center, there would still be a downward component of the total force applied to the CB by the tip, due to the shape of the CB and tip.

This, is why I believe in my personal experience I get significantly more swerve when shooting off the rail (forcing a very high tip placement on the CB) then when using a normal bridge and less high on the ball.
 
What tip position on the CB creates the most intentional swerve?
There are a wide range of tip positions and cue elevations that can be used to create a desired amount of swerve/curve/masse, based on the Coriolis aiming system described and demonstrated here:

masse shot aiming system resource page

The best combination will be what is most comfortable for you with the speed you intend to use.

Enjoy,
Dave
 
A small nit.... The path of the cue ball is a parabola from the time it leaves the tip until it starts rolling straight. That means it's curving right from the start.

The harder you hit it, the farther along the path it will travel with "less noticeable" deviation.
Yes, imagine the same curve stretched out somewhat "flatter" for harder hits, with the end paths parallel for both.
For those interested, a good illustration of the effect of speed with masse shots can be found in Diagram 2 of the following article:

"VEPS GEMS - Part XVI: The Masse Shot" (BD, April, 2011)

Regards,
Dave
 
If you have a perfectly level cue stick (end rail removed), and striking the CB above center, there would still be a downward component of the total force applied to the CB by the tip, due to the shape of the CB and tip.

This, is why I believe in my personal experience I get significantly more swerve when shooting off the rail (forcing a very high tip placement on the CB) then when using a normal bridge and less high on the ball.
There are several squirt and swerve effects that contribute to what you observe. For more info, see:

squirt and swerve draw/follow effects

Enjoy,
Dave
 
If you have a perfectly level cue stick (end rail removed), and striking the CB above center, there would still be a downward component of the total force applied to the CB by the tip, due to the shape of the CB and tip.

This, is why I believe in my personal experience I get significantly more swerve when shooting off the rail (forcing a very high tip placement on the CB) then when using a normal bridge and less high on the ball.
Yes, when shooting off the rail I often have to adust my aim for net swerve (opposite the correction for squirt).

pj
chgo

P.S. Not sure if you mean this by "due to the shape of the CB and tip": I think most (if not all) of the downward force is created by the CB rotating while in contact with the tip, pushing the tip upward and itself (the CB) downward - in other words, "vertical squirt". Also, with the CB trapped between the tip and the cloth the swerve happens immediately, hence the greater swerve effect.
 
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It's not possible to curve the CB without some vertical force (to create spin about a horizontal axis), but a truly level stroke is impossible unless the butt of your cue is not over a rail, so that probably explains your experience.


That's a good choice IMO. A small straight hop is more accurate than a curve.

pj
chgo

A level stroke can be accomplished regardless of the cueing angle by manipulation of elbow drop, shoulder drop and or wrist action.. Now if we manage to execute a level stroke with sidespin we will get no downward force vector if we cue on the horizontal axis and off center... I am to assume that we will no longer have to even consider swerve and only have to consider squirt as there will be no curve possible... I don't think I am buying it.. As long as there is rotation, friction and forward movement some curve has to occur unless the rotation turns to roll before the forward movement is slow enough for the friction and spin to interact...

It is an interesting concept tho and maybe the weight of the cueball is enough of a downward force and should be considered. Would explain why the 3 cushion guy spoke up first since those balls are larger and heavier.. Working on getting the high speed camera working and will put this on my list of things to try...

Chris
 
A level stroke can be accomplished regardless of the cueing angle by manipulation of elbow drop, shoulder drop and or wrist action.. Now if we manage to execute a level stroke with sidespin we will get no downward force vector if we cue on the horizontal axis and off center... I am to assume that we will no longer have to even consider swerve and only have to consider squirt as there will be no curve possible...
That is correct.

Sidespin does not cause the CB to curve (see ball "turn" for demos). Masse spin (or corkscrew spin, or barrel-roll spin) is required to make the CB curve. That type of spin is possible only if there is a downward and off-center component of force from the tip onto the CB. The more cue elevation you have, the more masse spin you get, and the more the CB curves.

With no cue elevation (i.e., a perfectly level cue with a hit through the horizontal centerline of the CB), there would be absolutely no masse spin or curve.

If you have "negative cue elevation" (the cue stick pointing up at the CB), as is possible with trick shots where the CB is supported on the rail on a piece of chalk, the CB actually curves in the opposite direction than with normal cue elevation. For example, hitting up on the CB with left spin would actually make the CB curve to the right (after it lands) ... not to the left as would be expected with a typical downward stroke.

I don't think I am buying it...
I hope it makes more sense now.

Regards,
Dave
 
That is correct.

Sidespin does not cause the CB to curve (see ball "turn" for demos). Masse spin (or corkscrew spin, or barrel-roll spin) is required to make the CB curve. That type of spin is possible only if there is a downward and off-center component of force from the tip onto the CB. The more cue elevation you have, the more masse spin you get, and the more the CB curves.

With no cue elevation (i.e., a perfectly level cue with a hit through the horizontal centerline of the CB), there would be absolutely no masse spin or curve.

If you have "negative cue elevation" (the cue stick pointing up at the CB), as is possible with trick shots where the CB is supported on the rail on a piece of chalk, the CB actually curves in the opposite direction than with normal cue elevation. For example, hitting up on the CB with left spin would actually make the CB curve to the right (after it lands) ... not to the left as would be expected with a typical downward stroke.

I hope it makes more sense now.

Regards,
Dave

No curve at all or no effective curve over the distances caused relevant by table size... And would increased spin/speed ratios possibly make the distances relevant? I am glad to see negative cueing angles mentioned.. The last time that one came up we had several posters swearing there was no such thing as an upstroke......
 
No curve at all or no effective curve over the distances caused relevant by table size... And would increased spin/speed ratios possibly make the distances relevant? I am glad to see negative cueing angles mentioned.. The last time that one came up we had several posters swearing there was no such thing as an upstroke......
If there is "positive" curve (to the left with left sidespin) for positive cue elevations (above horizontal) and "negative" curve (to the right with left sidespin) for negative cue elevations (below horizontal), then there must be zero curve with zero elevation.

So with a horizontal cue with an off-center hit on the horizontal centerline of the CB, the CB would head exactly in the squirt direction and not curve at all. In other words, the CB would head in a straight line with no swerve.

In fact, this is what we did when we designed a squirt-testing robot at Colorado State University. The CB did in fact head in a straight line so we could measure squirt (CB deflection) without having the results be influenced by swerve (which can vary with cloth conditions, tip efficiency, cue weight, and shot speed if the cue is not level). For more info, see squirt robot test results.

I hope you buy it now,
Dave
 
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If there is "positive" curve (to the left with left sidespin) for positive cue elevations (above horizontal) and "negative" curve (to the right with left sidespin) for negative cue elevations (below horizontal), then there must be zero curve with zero elevation.

So with a horizontal cue with an off-center hit on the horizontal centerline of the CB, the CB would head exactly in the squirt direction and not curve at all. In other words, the CB would head in a straight line with no swerve.

In fact, this is what we did when we designed a squirt-testing robot at Colorado State University. The CB did in fact head in a straight line so we could measure squirt (CB deflection) without having the results be influenced by swerve (which can vary with cloth conditions, tip efficiency, cue weight, and shot speed if the cue is not level). For more info, see squirt robot test results.

I hope you buy it now,
Dave

Getting Closer... Still window shopping.... LOL
 
The last time that one came up we had several posters swearing there was no such thing as an upstroke......

I think they said an up stroke had no influence. Or it was there's no reason to add this to the arsenal. Useless gibberish.
 
I think they said an up stroke had no influence. Or it was there's no reason to add this to the arsenal. Useless gibberish.

To be able to use an effective upstroke, one must do like the trickshot guys do....shoot up through the pocket. (can't do that on a lot of tables)
 
To be able to use an effective upstroke, one must do like the trickshot guys do....shoot up through the pocket. (can't do that on a lot of tables)

The bridge is a fulcrum... The tip can go up, down, straight, or sideways... IF your stroke ends with the butt of the cue lower than where you were at your setup it's effective if you want to carry english to the cueball without the cloth taking the spin off the ball from friction.... Not to be used all the time but definitely useful in certain situations where you don't want to hit the ball hard and need the spin to stay on the ball or even on long stroke shots like the 3 rail draw shot around the table that Earl shoots......
 
To be able to use an effective upstroke, one must do like the trickshot guys do....shoot up through the pocket. (can't do that on a lot of tables)

Neil, I don't want to reopen this upstroke thing other than to say there's disagreement. Not that its proof of relevance but 3 different US National 3C Champions have taught me shots using the upstroke. Just 2 weeks ago Geo Ashby showed me another one.

I have little idea of its usefulness in pool. BTW I gots no pockets, not even dirt slots on my table.:wink:
 
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