USEFUL SPEED REFERENCE for Judging Straight-Back-Bank CB Control and for Measuring a Table

[dr_dave]

FYI, I just posted a video that demonstrates a useful speed reference that is good to know. It is based on straight-back banks common in the game of One-Pocket, but the principle also applies to other games. It is also useful to measure the speed of a table and its cushions. This video is an excerpt from Volume IV of the Video Encyclopedia One Pocket (VEOP). Check it out:

As always, I look forward to your feedback, comments, questions, complaints, and requests.

Enjoy!

 

[dr_dave]

FYI, I just posted a video that demonstrates a useful speed reference that is good to know. It is based on straight-back banks common in the game of One-Pocket, but the principle also applies to other games. It is also useful to measure the speed of a table and its cushions. This video is an excerpt from Volume IV of the Video Encyclopedia One Pocket (VEOP). Check it out:

As always, I look forward to your feedback, comments, questions, complaints, and requests.

Enjoy!

If anybody tries to find the reference line on your table, please share with us where it is. I’m curious to hear results from typical Diamond tables.

 

[7stud]

9' Oval Blue Label Diamond in a pool hall with 1 year old cloth:

.8 of a diamond from the middle string towards the kicking rail.

Arghh. I used the 40-20 track. I'll try it again with the 30-15 track.

 

[Amaury]

"As always, I look forward to your feedback"
I am probably dumb but I can't understand this particular video at all... Even if you ask me what I didn't understood, I wouldn't know what to answer. What the goal of this video?

 

[straightline]

"As always, I look forward to your feedback"
I am probably dumb but I can't understand this particular video at all... Even if you ask me what I didn't understood, I wouldn't know what to answer. What the goal of this video?

Shot making references. In one hole it's desirable to play position in inopportune (for the opposition) (saved a lot of syllables there) spots. In the long bank za Doktor shows getting a long bank to the hole while sending the rock to the far end of the table and how to make note of certain dimensions and starting points.

 

[SlateMan]

"As always, I look forward to your feedback"
I am probably dumb but I can't understand this particular video at all... Even if you ask me what I didn't understood, I wouldn't know what to answer. What the goal of this video?

Forget the "reference line" and the bank. Ask yourself- If I want to hit a ball and leave the cue ball on the end rail, considering I use a constant stroke speed, how far does the cue ball travel? Can I then extrapolate that distance to other shots on the table to always know if I have to hit harder or softer to leave the ball on the end rail?

 

[dr_dave]

9' Oval Blue Label Diamond in a pool hall with 1 year old cloth:

Arghh. I used the 40-20 track. I'll try it again with the 30-15 track.

The track shouldn't matter much. If you use pocket speed on any track, the CB should still finish close to the head rail.

 

[dr_dave]

"As always, I look forward to your feedback"
I am probably dumb but I can't understand this particular video at all... Even if you ask me what I didn't understood, I wouldn't know what to answer. What the goal of this video?

I bet if you watch the video again, after reading the comments above, it will be more clear. Even better, try it out at a table to see where the OB needs to be relative to the side pockets so a pocket-speed straight-back bank leaves the CB on the head rail.

 

[Poolmanis]

This very simple video that Dave made is one of many "secrets" of learning the game better, more simply way.

Where this principle really shines is safety play all games. Often players use rolling ball to get safety shot but they try get both balls places where they are not possible to go.
Example:
One cut half inch to left and try hook opponent behind ball close to corner pocket, and while doing so you also try get object ball to another end of table. Doing so it might be that when object ball is going to another end of table cueball have too much speed to get hook that is intended. If hook is essential object ball maybe should come 2 diamonds short of end rail.
So that is practice thing shoot those shots and observe both ball speeds. Also thickness of cut have to be aware of so one can learn faster and better.

 

[dr_dave]

This very simple video that Dave made is one of many "secrets" of learning the game better, more simply way.

Where this principle really shines is safety play all games. Often players use rolling ball to get safety shot but they try get both balls places where they are not possible to go.
Example:
One cut half inch to left and try hook opponent behind ball close to corner pocket, and while doing so you also try get object ball to another end of table. Doing so it might be that when object ball is going to another end of table cueball have too much speed to get hook that is intended. If hook is essential object ball maybe should come 2 diamonds short of end rail.
So that is practice thing shoot those shots and observe both ball speeds. Also thickness of cut have to be aware of so one can learn faster and better.

Well stated. Thank you for posting this.

 

[bbb]

Isnt there a ratio for how far a cue ball rolls relative to the object ball on a full hit or other hits?

 

[Bob Jewett]

This kind of info is most useful at one pocket for pool games. At one pocket, you often have to control both the object ball and the cue ball final positions. In most other pool games, you drive the object ball into the pocket and set your speed by how far you want the cue ball to go -- you control only one ball speed.

As @Poolmanis pointed out, you do need to control both ball speeds when playing safe at other pool games. Well, sometimes you can get away with controlling just one speed, but the best safeties control both balls.

 

[Bob Jewett]

Isnt there a ratio for how far a cue ball rolls relative to the object ball on a full hit or other hits?

For a full hit with a rolling cue ball, the cue ball rolls 1/6th as far as the object ball if no rail is struck. This depends a little on how sticky the balls are as a "heavy contact" will ruin the follow on the cue ball.

That means the cue ball will roll roughly one ball diameter for each diamond of object ball travel.

 

[dr_dave]

For a full hit with a rolling cue ball, the cue ball rolls 1/6th as far as the object ball if no rail is struck. This depends a little on how sticky the balls are as a "heavy contact" will ruin the follow on the cue ball.

That means the cue ball will roll roughly one ball diameter for each diamond of object ball travel.

The 6x factor is for ideal (highly polished balls). At the bottom of TP A.16 – Final ball speeds, distances, and directions for natural roll shots, I show that for typical ball condition, it is closer to 7x.

Here's a demonstration:

 

[Badpenguin]

Yeah, sorry Dave, but the entire reference line concept in this video does not make any sense. Can't really figure out where you are trying to go with this.

 

[dr_dave]

Yeah, sorry Dave, but the entire reference line concept in this video does not make any sense. Can't really figure out where you are trying to go with this.

Well, if the video (after multiple viewings) and the comments from Poolmanis and Bob Jewett above don't make sense, then the information will probably not be useful to you, but I encourage you to try the shots described in the video and attempt to find the reference line on a chosen table. That exercise might teach you something and give you some useful speed-control practice.

 

[Badpenguin]

Well, if the video (after multiple viewings) and the comments from Poolmanis and Bob Jewett above don't make sense, then the information will probably not be useful to you, but I encourage you to try the shots described in the video and attempt to find the reference line on a chosen table. That exercise might teach you something and give you some useful speed-control practice.

I have no idea what your reference line is referencing ;(

 

[dr_dave]

I have no idea what your reference line is referencing ;(

... where the OB needs to be relative to the side-pocket line for a pocket-speed straight-back bank to leave the CB on the head rail.

 

[Badpenguin]

Come on Dave, this is nonsense. Where the cue ball ends up depends on stroke speed, tip position, cloth conditions, humidity, how far the cue ball is from the object ball, etc... There is no arbitrary reference line that is going to determine where that cue ball ends up, this is really, really reaching.

 

[7stud]

Come on Dave, this is nonsense. Where the cue ball ends up depends on stroke speed,

Yes. You have to stroke the CB so that it ends up on the end rail, then you observe where the OB ended up: if it was short of the pocket, then you need to put the OB further from the banking rail and hit the CB harder. If the OB rolls into the pocket with excess speed, then you need to move the OB closer to the banking rail and hit the CB softer.

tip position

The CB has to achieve full roll before hitting the OB---whatever tip position you need to accomplish that is the required tip position. If the CB is a few feet from the OB, you can probably get away with hitting slightly above center ball; and if the CB is close to the OB, you will need "instant roll" or a tip position that is 40% of the radius above the equator of the CB.

, cloth conditions, humidity,

Irrelevant for a given table at the time of testing the table speed. Can a table's speed change? Sure, and when the table speed changes a player can recognize that and adjust.

how far the cue ball is from the object ball, etc...

As long as the CB arrives at the OB with full roll and the correct speed then the OB has no idea how far away the CB was when you struck it. In other words, full roll and the speed completely describe how the CB is moving when it impacts the OB. Therefore, it doesn't matter how far away the CB is from the OB as long as the CB is rolling and has slowed down to the correct speed when it hits the OB. Thought experiment: suppose the CB is 1 foot from the OB, and a slow speed hit, with a full rolling CB, will sink the OB and bring the CB 6 inches off the rail. Does that mean that if the CB is 8 diamonds distance from the OB, it is impossible to leave the CB 6 inches off the rail? Of course not: you can hit the CB at a speed such that when it arrives at the OB it is rolling at the exact same speed as the short shot, and therefore the CB will also rebound six inches off the rail.

There is no arbitrary reference line that is going to determine where that cue ball ends up, this is really, really reaching.

I was able to determine a reference line when I tried it. The reference line does not determine where the CB will end up, rather the reference line tells you that if you have the touch to make the CB end up nestled against the end rail and the OB started on the reference line, then the OB will just trickle into the pocket or hang on the edge of the pocket.