Another "Learn to See Fractions" Practice Tip

Patrick Johnson

Fish of the Day
Silver Member
With an OB anywhere on one of the black lines, shoot the CB parallel with the long rails to hit the OB with the fractional overlap for that line and pocket the OB in the upper right corner.

The lines are fairly easily remembered by their end points on the left and bottom rails - all end on diamonds except the 1/4 ball cut.

pj
chgo

P.S. The exact fractional cut angles intersect the rails slightly off the diamonds here and there (red marks in the pic), but only the 5/8 and 1/8 fractions are off a noticable amount.

Fractions Practice Lines.jpg
 
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BC21

Poolology
Gold Member
Silver Member
These are the same old traditional lines people have been showing for years, and they are off by a few degrees. In fact, Stan Shuffett has a video where he sets up a "30° shot" using this 1/2 ball line you show here, where the 30° angle is based on the center-to-center line between the balls, NOT the aim line from center cb to ob edge. The shot is actually a 3/8 and can't be made using a 1/2 ball aim unless you spin it with outside english. Dan White analyzed the stroke on this shot and shows where Stan uses outside spin to account for the fact that this isn't really a dead halfball shot.

Here is Stan's video....https://youtu.be/AMmmhtZqA1U.

Set the shot up exactly as he describes and you'll see that the ob is on the 1/2 ball line shown in your diagram. The ob is half a diamond away from the center spot and the cb is 1 diamond away from the head spot, lined straight/perpendicular to the end rail. Shoot a halfball shot as he describes, or as your diagram indicates, and the ob hits the end rail, not the pocket. Here's why....

The distance between the cb and ob is 1.5 diamonds, 18.75" on a 9ft table. Stan (and your diagram) reference a 30° angle from a center cb to center ob perspective. But when you aim ccb to ob edge, you shift your ccb perspective exactly 3.4° to the right. asin(1.125/18.75) = 3.4°. You create a 30° angle, but it's shifted to the right of the pocket, and once you factor in throw it shifts even farther right of the pocket, sending the ob about half a diamond too thick.

A more accurate line to reference the 1/2 ball shot and other angles must incorporate this change in perspective, the difference between a center cb to center ob perspective and a center cb to required ob aim point perspective, which is shown here.....
https://forums.azbilliards.com/showthread.php?t=502020
 
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8pack

They call me 2 county !
Silver Member
With an OB anywhere on one of the black lines, shoot the CB parallel with the long rails to hit the OB with the fractional overlap for that line and pocket the OB in the upper right corner.

The lines are fairly easily remembered by their end points on the left and bottom rails - all end on diamonds except the 1/4 ball cut.

pj
chgo

P.S. The exact fractional cut angles intersect the rails slightly off the diamonds here and there (red marks in the pic), but only the 5/8 and 1/8 fractions are off a noticable amount.

View attachment 535786

Your close an even if you were on by your lines your still off in the resl world of 2 balls colliding.
 

Patrick Johnson

Fish of the Day
Silver Member
Stan (and your diagram) reference a 30° angle from a center cb to center ob perspective.
My instructions are to "shoot the CB parallel with the long rails to hit the OB with the fractional overlap". That's only possible when the CB is aligned properly with the ghost ball.

pj
chgo
 

bbb

AzB Gold Member
Gold Member
Silver Member
These are the same old traditional lines people have been showing for years, and they are off by a few degrees. In fact, Stan Shuffett has a video where he sets up a "30° shot" using this 1/2 ball line you show here, where the 30° angle is based on the center-to-center line between the balls, NOT the aim line from center cb to ob edge. The shot is actually a 3/8 and can't be made using a 1/2 ball aim unless you spin it with outside english. Dan White analyzed the stroke on this shot and shows where Stan uses outside spin to account for the fact that this isn't really a dead halfball shot.

Here is Stan's video....https://youtu.be/AMmmhtZqA1U.

Set the shot up exactly as he describes and you'll see that the ob is on the 1/2 ball line shown in your diagram. The ob is half a diamond away from the center spot and the cb is 1 diamond away from the head spot, lined straight/perpendicular to the end rail. Shoot a halfball shot as he describes, or as your diagram indicates, and the ob hits the end rail, not the pocket. Here's why....

The distance between the cb and ob is 1.5 diamonds, 18.75" on a 9ft table. Stan (and your diagram) reference a 30° angle from a center cb to center ob perspective. But when you aim ccb to ob edge, you shift your ccb perspective exactly 3.4° to the right. asin(1.125/18.75) = 3.4°. You create a 30° angle, but it's shifted to the right of the pocket, and once you factor in throw it shifts even farther right of the pocket, sending the ob about half a diamond too thick.

A more accurate line to reference the 1/2 ball shot and other angles must incorporate this change in perspective, the difference between a center cb to center ob perspective and a center cb to required ob aim point perspective, which is shown here.....
https://forums.azbilliards.com/showthread.php?t=502020
here is patricks and brians diagrams
when i saw your diagram
patrick i wondered why it was different from brians and another from a great pdf the art of something
i know i had downloaded that and a poster posted a pic from it on another thread in this forum
i just cant find it
if anyone knows what i am talking about and has a link to the pdf i would be VERY APPRECIATIVE TO HAVE IT
thank you brian for explaining the difference
patricks fractional lines.jpg

brian fraction lines.jpg
 

BC21

Poolology
Gold Member
Silver Member
My instructions are to "shoot the CB parallel with the long rails to hit the OB with the fractional overlap". That's only possible when the CB is aligned properly with the ghost ball.

pj
chgo

Ok. So anyone trying to use the lines would just have to be able to recognize when the cb and ghostball (not ob) are both parallel with the side rails? It is much easier to reference the cb to ob center line because there isn't as much guesswork involved as there is when you have to imagine a ghostball.
 

Dan White

AzB Silver Member
Silver Member
My instructions are to "shoot the CB parallel with the long rails to hit the OB with the fractional overlap". That's only possible when the CB is aligned properly with the ghost ball.

pj
chgo

You might want to be more clear about that next time. I'm pretty sure 99.99% of readers thought you were saying to put the cue ball parallel to the long rail so that the two balls were parallel. You were trying to recommend putting the cue ball/ghost ball alignment parallel to the long rail, which of course will not leave the cb/ob alignment parallel.
 

Dan White

AzB Silver Member
Silver Member
Ok. So anyone trying to use the lines would just have to be able to recognize when the cb and ghostball (not ob) are both parallel with the side rails? It is much easier to reference the cb to ob center line because there isn't as much guesswork involved as there is when you have to imagine a ghostball.

Just use CTE. No ghost balls need apply!
 

Patrick Johnson

Fish of the Day
Silver Member
Ok. So anyone trying to use the lines would just have to be able to recognize when the cb and ghostball (not ob) are both parallel with the side rails? It is much easier to reference the cb to ob center line because there isn't as much guesswork involved as there is when you have to imagine a ghostball.
There's no ghostball to imagine - I only mentioned it to show the accuracy of the alignment. The CB is aligned with the appropriate fraction of the OB, which of course is the point of the practice.

pj
chgo
 

Low500

AzB Silver Member
Silver Member
These are the same old traditional lines people have been showing for years, and they are off by a few degrees. In fact, Stan Shuffett has a video where he sets up a "30° shot" using this 1/2 ball line you show here, where the 30° angle is based on the center-to-center line between the balls, NOT the aim line from center cb to ob edge. The shot is actually a 3/8 and can't be made using a 1/2 ball aim unless you spin it with outside english. Dan White analyzed the stroke on this shot and shows where Stan uses outside spin to account for the fact that this isn't really a dead halfball shot.
Here is Stan's video....https://youtu.be/AMmmhtZqA1U.
Set the shot up exactly as he describes and you'll see that the ob is on the 1/2 ball line shown in your diagram. The ob is half a diamond away from the center spot and the cb is 1 diamond away from the head spot, lined straight/perpendicular to the end rail. Shoot a halfball shot as he describes, or as your diagram indicates, and the ob hits the end rail, not the pocket. Here's why....
The distance between the cb and ob is 1.5 diamonds, 18.75" on a 9ft table. Stan (and your diagram) reference a 30° angle from a center cb to center ob perspective. But when you aim ccb to ob edge, you shift your ccb perspective exactly 3.4° to the right. asin(1.125/18.75) = 3.4°. You create a 30° angle, but it's shifted to the right of the pocket, and once you factor in throw it shifts even farther right of the pocket, sending the ob about half a diamond too thick.
A more accurate line to reference the 1/2 ball shot and other angles must incorporate this change in perspective, the difference between a center cb to center ob perspective and a center cb to required ob aim point perspective, which is shown here.....
https://forums.azbilliards.com/showthread.php?t=502020
Man oh man, you're just as clueless as ever.
In fact I think you're getting worse.
:boring2:
 

BC21

Poolology
Gold Member
Silver Member
There's no ghostball to imagine - I only mentioned it to show the accuracy of the alignment. The CB is aligned with the appropriate fraction of the OB, which of course is the point of the practice.

pj
chgo

Ok, I'm pick'n up what you're lay''n down now. That makes it a lot easier.:)
 

BC21

Poolology
Gold Member
Silver Member
Man oh man, you're just as clueless as ever.
In fact I think you're getting worse.
:boring2:

Set the shot up that I've referenced. It cannot be pocketed with a halfball hit as Stan says in the video, unless outside spin is used.

I'm sorry if this conversation is over your head. Maybe you don't understand what a halfball shot is. Or maybe you have trouble hearing or comprehending Stan's instructions in the video. But calling me clueless about fractional aiming tells me that either you don't know any better or you just choose to ignore basic common sense.

Anyway, most people don't post in threads they consider "boring", unless they're trolling, or cheerleading.
:thumbup:
 

JoeyInCali

AzB Gold Member
Gold Member
Silver Member
Set the shot up that I've referenced. It cannot be pocketed with a halfball hit as Stan says in the video, unless outside spin is used.

I'm sorry if this conversation is over your head. Maybe you don't understand what a halfball shot is. Or maybe you have trouble hearing or comprehending Stan's instructions in the video. But calling me clueless about fractional aiming tells me that either you don't know any better or you just choose to ignore basic common sense.

Anyway, most people don't post in threads they consider "boring", unless they're trolling, or cheerleading.
:thumbup:
Uh oh, where's Dan's videos?
 
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BC21

Poolology
Gold Member
Silver Member
Uh oh, where's Dan's videos?

Good idea. Maybe Low would get it if he watched Dan's videos. Here's one....https://youtu.be/wpljeVvOqRs

Just about anyone should be able to understand that a halfball hit (30° cut) won't work on a shot that needs about a 36° cut, especially when the margin of error is only +/- 1.4°. Shooting a halfball shot here, factoring in a couple of degrees for throw, would send the ob into the end rail a good 3 or 4 inches from the pocket.

Nobody has to take my word for it. The proof is in the shot -- shoot it and watch the results.
 
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