Problem With Our Understanding Of Side

Imac007

AzB Silver Member
Silver Member
General player understanding of side/english usually relates to the aim line through center ball. That line extends to the target, an object ball when potting, which is roughly the ghost ball location. Paradoxically the physics of spin on the object ball doesn’t care about the target line. When parallel english is used the line and direction of force will coincide with the target line. When any other version of side application is used, the direction of force and its relationship to a parallel line through the center of mass are the common denominator. FHE and BHE each have lines of force that don’t care about the shot line in their calculations. Deflection calculations are a different matter. The relationship between contact point, contact angle, approach angle, tip shape, chalk and coefficient of friction all factor into eventual force dynamics after impact, including deflection calculations, but the original target line is not found in those equations, except with parallel english.

Basically the line of force through the ball when side is used, has a parallel relationship to a line running through the center of mass. In other words the physics math is different for FHE than for BHE or parallel english, because the line paralleling each type of english, through the center of mass, is on a different plane. Parallel english finds the force line through the center of mass coincides with the target line. The paradox is that regardless of which type of english is used the reference used has been the target line, usually measured in tips of english. But tips of english from the ghost ball line won’t tell you the length of the torque line. In other words it doesn’t tell you how much side is really being applied on the ball, except when using parallel side.

A closer look is enlightening. We know that the cueing angle through the ball is related in physics math to a parallel line running through the center of mass, not a spot on the surface. The center of the ball is the true reference point. The distance of the cueing line to the paralleling line through that center is a torque arm, the length of that line is used in spin calculations. I call it simply the torque line.

There is a problem in perception because the ghost ball line, not the paralleling line through the center, has been used as the reference. Using that as the perspective has all perceived lines of english radiating from or paralleling the ghost ball line. Using those diverging lines the game has missed a whole range of angles with side, not currently used in play. The implications are huge.

Our fixation on the target line, when describing side, is only relevant when parallel english is used. In essence every type of side’s, force line, is parallel in nature, only that parallel line, doesn’t correlate to the target line. Various deflection, curved ball travel dynamics, combined with aim adjustments, and margin of error characteristics, allow balls to arrive in the same impact zone and pocket balls, despite our understanding reference being flawed.

If anyone is interested I will explain the missed versions of side, how to apply them, how to adjust for each and their uses in potting and playing position. There is some basic geometry, mainly ratios, in the explanations but no real math otherwise.

Some references to Dr. Dave physics results will be used as references for validation.

ADDENDUM: A poster on a later page suggested a glossary at the beginning to make reading easier.
Parallel English - aiming technique when using sidespin where the cue is placed parallel to the line of aim for a center-ball hit (with no sidespin) resulting in no compensation for CB deflection (e.g., for shots where swerve is expected to cancel the effects of squirt and throw, resulting in no net CB deflection, or where the amount of resulting pocket cheat is acceptable).
Corollary - Lines that are not parallel will intersect at some point
Divergent English - where the cue placement is not parallel to the center ball aim line. The line the cue is on will cross the center ball aim line on the player side of the cue ball.
BHE - a type of divergent english where the cue line diverges from the current ball aim line at the bridge
FHE - a type of divergent english where the cue line diverges from the current aim line at the grip location
Convergent English - where the cue placement is not parallel to the center ball aim line. This line converges with the current aim line on the other side of the cue ball from the player aim position.
 
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ShootingArts

Smorg is giving St Peter the 7!
Gold Member
Silver Member
Have fun Imac!

PJ is of course playing games. He is well aware of what is referred to as parallel english. He has also maintained for decades that the angle the cue stick hits the cue ball doesn't matter, only the location. After thirty years most have given up on trying to change his firmly held opinions although it is easy to demonstrate the lack of truth by exaggerating the angle.

The location of contact one tip to the side of centerline can be a very commonly and successfully used shot, or by moving the bridge and exaggerating the angle it can be an impossible to shoot successfully miscue. Yet PJ's claim has always been that the angle doesn't matter, only the location.

Having ran this rabbit many times before with PJ I'll sit this one out other than saying you are absolutely right about lines of force. Hitting exactly the same spot with backhand english, fronthand english and parallel offset english will each give different results. It is also possible to combine multiple forms of english in one shot with good results sometimes.

I never tried front hand english until after using either parallel or back hand english for many years. Seems odd and I never used it long enough for it to become natural but because the angle is less severe it seems superior to back hand english. I usually use parallel english, just a matter of what I am most comfortable with.

All three work, combinations of English work. Poking another sacred cow but something your post makes obvious you will understand, each form of english lets you hit a different distance out from centerline before a miscue occurs when the target line is used as reference.

Since the lines of force are different and the force that can be applied without a miscue remain the same I have suspected that the angle the cue ball is hit and the distance that the cue ball can be hit without miscueing can only apply the same amount of force through the true vertical line of the cue ball from top center to contact patch, the amount of spin possible on the cue ball remains the same.

I have never seen this physically proven by testing with a robot to eliminate the human factor and have long wanted to see it proven if any of the three types of english or any combination can gain a slight advantage. I think not but that remains unproven as far as I know. I don't wholly trust mathematical proof of such things as I have seen the formulas of similar calculations leave out small variables that affect real world outcomes enough to render the calculations false.

Hu
 

Patrick Johnson

Fish of the Day
Silver Member
PJ is of course playing games. He is well aware of what is referred to as parallel english. He has also maintained for decades that the angle the cue stick hits the cue ball doesn't matter, only the location.
None of this is true (assuming by "angle of the cue stick" you mean the direction of the tip's motion - usually they're the same).

What's your definition of "parallel" english?

pj
chgo
 
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ShootingArts

Smorg is giving St Peter the 7!
Gold Member
Silver Member
None of this is true (assuming by "angle of the cue stick" you mean the direction of the tip's motion - usually they're the same).

What's your definition of "parallel" english?

pj
chgo



pj,

Feel free to do a search and read the last seventeen times we have discussed such things, I'm not playing again.



erhino,

This doesn't seem to be as much about aiming as the affects of english and perhaps bettering the general understand of the affects of the various ways of using english. I think with better understanding, fewer might use back hand english or back hand english alone. I hope this thread remains on the main forum.

Hu
 

garczar

AzB Silver Member
Silver Member
None of this is true (assuming by "angle of the cue stick" you mean the direction of the tip's motion - usually they're the same).

What's your definition of "parallel" english?

pj
chgo
Not trying to start a fire here but where do get all your info? You seem to make statements as if we are all morons for even questioning your takes. Do you have degree in physics? Seriously, i'm curious as to what your background/education/training is. I like reading most of your stuff but i rarely reply 'cause almost every topic ends in a flame war.
 

BC21

https://www.playpoolbetter.com
Gold Member
Silver Member
I don't believe there are any "missed versions" or unknown effects of side spin. Experienced players develop a good feel for spin and automatically adjust for it based on their particular cue.

When using parallel english, and you really know the feel of your cue, you know exactly how far from center cb you can hit before you have to start compensating or adjusting from that parallel line, angling your cue more to account for more cb squirt (using BHE or FHE or a mix of the two).

Not every shaft plays the same, so even though there are some basic adjustments that one learns over time, changing to a cue with more shaft deflection (or less deflection) will require a re-tuning of adjustments when using side spin.
 

garczar

AzB Silver Member
Silver Member
I don't believe there are any "missed versions" or unknown effects of side spin. Experienced players develop a good feel for spin and automatically adjust for it based on their particular cue.

When using parallel english, and you really know the feel of your cue, you know exactly how far from center cb you can hit before you have to start compensating or adjusting from that parallel line, angling your cue more to account for more cb squirt (using BHE or FHE or a mix of the two).

Not every shaft plays the same, so even though there are some basic adjustments that one learns over time, changing to a cue with more shaft deflection (or less deflection) will require a re-tuning of adjustments when using side spin.
Well put. I don't why all the animus over what is/isn't parallel english. I still use "it" on softer spin shots and then use bhe/fhe combo on higher speed spinners. When i was at DCC in '07 i noticed Efren(not comparing me to him in any way) kinda did same thing, parallel on softer shots and then swinging his cue on harder shots.
 

Patrick Johnson

Fish of the Day
Silver Member
\When using parallel english, and you really know the feel of your cue, you know exactly how far from center cb you can hit before you have to start compensating or adjusting from that parallel line, angling your cue more to account for more cb squirt
I don't believe there's any amount of sidespin that doesn't generate some squirt. It may be offset exactly by swerve at some distances/speeds/elevations/conditions, but that's a variable, not something that's "automatic" for small amounts of sidespin.

If "parallel english" means "cue parallel to the shot line", I think it's an unrealistic and misleading term - because it's so rarely true, it obscures the physical facts of squirt and how we compensate for it, and it encourages habitual practices that limit our games.

pj
chgo
 

Seth C.

AzB Silver Member
Silver Member
Well put. I don't why all the animus over what is/isn't parallel english. I still use "it" on softer spin shots and then use bhe/fhe combo on higher speed spinners. When i was at DCC in '07 i noticed Efren(not comparing me to him in any way) kinda did same thing, parallel on softer shots and then swinging his cue on harder shots.

I’d be very interested in and appreciative of an explanation of why each of the different methods is best suited to various shots.
 

erhino41

AzB Silver Member
Silver Member
erhino,



This doesn't seem to be as much about aiming as the affects of english and perhaps bettering the general understand of the affects of the various ways of using english. I think with better understanding, fewer might use back hand english or back hand english alone. I hope this thread remains on the main forum.



Hu

Nope. Everything the op wrote was in reference to aiming. Except the last paragraph were he alluded to some unknown uses for English that no-one but him had figured out as of yet.

Sent from my LG-H918 using Tapatalk
 

Patrick Johnson

Fish of the Day
Silver Member
When i was at DCC in '07 i noticed Efren(not comparing me to him in any way) kinda did same thing, parallel on softer shots and then swinging his cue on harder shots.
By "swinging his cue" do you mean "swooping/swiping" in a curved stroke?

Then is "parallel" english any time you don't swoop/swipe (any time you stroke straight, even if it's at an angle to the shot line)?

pj
chgo
 

garczar

AzB Silver Member
Silver Member
By "swinging his cue" do you mean "swooping/swiping" in a curved stroke?

Then is "parallel" english any time you don't swoop/swipe (any time you stroke straight, even if it's at an angle to the shot line)?

pj
chgo
Sorry. I meant bhe, not a swoop. To me parallel is just that, moving your whole cue parallel left/right of your straight at it stroke. Brings a lot of squirt into play unless your using an ld shaft.
 

Patrick Johnson

Fish of the Day
Silver Member
Sorry. I meant bhe, not a swoop.
And by BHE you mean angling the cue with BHE and then stroking straight along that angled line?

To me parallel is just that, moving your whole cue parallel left/right of your straight at it stroke. Brings a lot of squirt into play unless your using an ld shaft.
And misses all shots except those where swerve (a variable depending on distance, speed, conditions, butt elevation, etc.) happens to exactly counteract squirt, right?

pj
chgo
 

garczar

AzB Silver Member
Silver Member
And by BHE you mean angling the cue with BHE and then stroking straight along that angled line?


And misses all shots except those where swerve (a variable depending on distance, speed, conditions, butt elevation, etc.) happens to exactly counteract squirt, right?

pj
chgo
Just adjust aim for the deflection. Hit enough ball with same cue and its not a big deal. Until i learned what bhe/fhe were i always made a full cue shift. Just figured it out by playing. Call it whatever you want but that's i grew up playing.
 

Patrick Johnson

Fish of the Day
Silver Member
Just adjust aim for the deflection. Hit enough ball with same cue and its not a big deal. Until i learned what bhe/fhe were i always made a full cue shift. Just figured it out by playing. Call it whatever you want but that's i grew up playing.
OK. I'm still not sure what you mean by "parallel", but moving along...

pj
chgo
 
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