PDA

View Full Version : Double hits - A "chalk cube's distance" means nothing!

Billy_Bob
03-04-2005, 05:43 AM
Double hits are possible with the cue ball 6 inches away from the object ball! (Let alone a chalk cube's distance.)

A double hit can occur if the "stroke follow through" is more than the distance between the cue ball and the object ball.

Since a 6 inch follow through or more is common with many players, a cue ball 6 inches or less away from the object ball is in danger of a double hit.

The symptoms of a double hit are:
-The cue ball "immediately" follows the object ball.
-The cue ball closely follows the object ball.
-The cue ball does not "hesitate" or "stop" prior to following the object ball in the case of a follow shot.
-A "double click" sound can be heard when the balls are further apart (difficult to hear when balls are close together).

The symptoms of a single hit are:
- The cue ball stops.
- A single "click" sound is heard (if balls are very close together, a double click may sound like a single click).
- In the case of a follow shot, the cue ball briefly "stops" or "hesitates" prior to proceeding forward. (So just because the cue ball follows the object ball, this does not in itself mean that it was a double hit!)
- The cue ball follows further behind the object ball due to the delay caused by the brief "stop" or "hesitation".

Experiment with the above. Follow through longer than 6 inches with the cue ball 6 inches from the object ball and watch the double hit. Try single hit follow shots and watch the cue ball hesitate prior to proceeding forward.

You can hit directly at the cue ball when it is less than a chalk cubes distance from the object ball and have a good hit! It is called a "nip" shot....

How to shoot a perfect nip shot every time and avoid double hits...

It is simple. During a normal stroke, your arm can only move so far forward until it is at the end of the follow through of your stroke. So..... Begin your nip shot stroke with your hand fully forward - fully extended at the end of its stroke so that you can only stroke forward and additional 1/8 inch, or 1/4 inch or so. Your arm can't move any more forward since it is already all the way forward!

So before shooting a nip shot or a shot where the cue ball is 6 inches or less away from the cue ball, extend your arm fully forward or stand further back, then practice stroking to the side of the cue ball. Be sure that you will not stroke further past the cue ball more than the distance between the cue ball and object ball.

Note: There is also a nip follow shot and a nip draw shot.

(BTW - I will be out of town for a few weeks, so will not be able to respond to this thread for awhile....)

piglit
03-04-2005, 05:52 AM
Double hits are possible with the cue ball 6 inches away from the object ball! (Let alone a chalk cube's distance.)...(BTW - I will be out of town for a few weeks, so will not be able to respond to this thread for awhile....)

Look at ya! Throwin' a rock like that and then runnin' away!

My recollection of the intention of the 'cube distance' reference was that it was merely a guideline to provide an example where the circumstances might lead to a double hit. It was not a definition of the (only) condition under which it might occur.

-piga

sjm
03-04-2005, 05:57 AM
Nice post, BillyBob, although the chalk width is a gudieline that remains significant.

DaveK
03-04-2005, 09:44 AM
Look at ya! Throwin' a rock like that and then runnin' away!

My recollection of the intention of the 'cube distance' reference was that it was merely a guideline to provide an example where the circumstances might lead to a double hit. It was not a definition of the (only) condition under which it might occur.

-piga

Ya, so take that BB ! :D

We play the 45 degree within a chalk cube rule. What this means is that a foul CANNOT be called if the criteria are met. That in itself is pretty meaningful within our league.

Like most rules, it is somewhat arbitrary, and it could have be set with a distance of 11.6 mm , 0.684 inches, or a large number of angstroms. The cube of chalk is simply a pretty good measuring device for billiards related purposes, with myself being one of the very few who might bring sophisticated measuring devices to the pool hall. Having said that, double-hit fouls can be made when the distance is larger, I agree. It's just that the rule we play does not come into play in any situation other than the 'closer than chalk' layout. The shooter has to declare this rule applys before shooting. The opponent can argue, but of course either can use a cube of chalk to decide if the rule applys or not. I've never seen a fight over this rule, unlike other situations that arise.

Dave

PS Billy_Bob you did a good job of describing how one can distinguish between a good hit and a double hit.

Tbeaux
03-04-2005, 09:54 AM
I'm confused here.Maybe it's just symantics but I always thought a "DOUBLE HIT" was when the cue stick contacted the cue ball twice on the same shot. Thought a "DOUBLE KISS" was when cue ball and object ball contacted twice when in close proximity?I always try to avoid both.

DoomCue
03-04-2005, 10:12 AM
I'm confused here.Maybe it's just symantics but I always thought a "DOUBLE HIT" was when the cue stick contacted the cue ball twice on the same shot. Thought a "DOUBLE KISS" was when cue ball and object ball contacted twice when in close proximity?I always try to avoid both.
Your definition of "DOUBLE HIT" is correct, and you can expand "DOUBLE KISS" to pertain to any balls instead of just CB and OB. The thread here is about double hits, which are illegal, and how to judge them. There's nothing illegal about a double kiss.

-djb

Zims Rack
03-04-2005, 12:10 PM
Looks like Billy Bob has been watching the BSACA videos!!! Great job! and Good luck!

Zim

Bob Jewett
03-04-2005, 12:42 PM
...
We play the 45 degree within a chalk cube rule. What this means is that a foul CANNOT be called if the criteria are met. That in itself is pretty meaningful within our league. ...
So it's OK to hit the cue ball multiple times if elevated. My own feeling is that it's better to educate the players on what the balls are doing and train them to determine when douible hits occur, and get them to accept the rulings of referees when necessary. But I recognize that in some league situations, such a solution will never happen. I wonder if the people who made up the 45-degree rule are aware that it has almost no bearing on the occurence of a double hit. Also, I'd be willing to bet that many of the shots are played with less than 45 degrees of elevation.

How do you generally handle the situation when the balls are slightly more than a chalk apart?

Rackin_Zack
03-04-2005, 02:22 PM
Ya, so take that BB ! :D

We play the 45 degree within a chalk cube rule. What this means is that a foul CANNOT be called if the criteria are met. That in itself is pretty meaningful within our league.

Like most rules, it is somewhat arbitrary, and it could have be set with a distance of 11.6 mm , 0.684 inches, or a large number of angstroms. The cube of chalk is simply a pretty good measuring device for billiards related purposes, with myself being one of the very few who might bring sophisticated measuring devices to the pool hall. Having said that, double-hit fouls can be made when the distance is larger, I agree. It's just that the rule we play does not come into play in any situation other than the 'closer than chalk' layout. The shooter has to declare this rule applys before shooting. The opponent can argue, but of course either can use a cube of chalk to decide if the rule applys or not. I've never seen a fight over this rule, unlike other situations that arise.

Dave

PS Billy_Bob you did a good job of describing how one can distinguish between a good hit and a double hit.

That would be 1.16x10^8 angstroms! 1mm = 10^-3m and 1A = 10^-10m. Or you could say that an angstrom is an order of magnitude smaller than a nanometer. :D Just an FYI...lol.

Also, what about the fact that the cuetip will hit the cueball many times before the cueball's speed increases beyond that of the cue stick? Should there be a maximum time between hits such as 100ns. or how ever long is typical? :D :D :D

Johnson
03-04-2005, 02:41 PM
for the most part i understand the chalk length away rules, but what if the balls are frozen together, does this rule apply? anytime i've been informed about this rule there was never a stipulation if the balls are frozen together? i saw a tony drago shot where he had a frozen ob cb, and he shot without jacking up, all he really did was cut it thin and play safe, and then i saw allen hopkins in one of his tips at the champions of champions, where he had ob cb frozen together and he all but shot str8 at it and said that it was a legal shot because of how they where set up?
________
Sunset Boulevard Residence Prathumnak (http://pattayaluxurycondos.com)

Rackin_Zack
03-04-2005, 02:43 PM
for the most part i understand the chalk length away rules, but what if the balls are frozen together, does this rule apply? anytime i've been informed about this rule there was never a stipulation if the balls are frozen together? i saw a tony drago shot where he had a frozen ob cb, and he shot without jacking up, all he really did was cut it thin and play safe, and then i saw allen hopkins in one of his tips at the champions of champions, where he had ob cb frozen together and he all but shot str8 at it and said that it was a legal shot because of how they where set up?

I saw that too and was always told that was a foul, even though Hopkins said that it wasn't?!

DaveK
03-04-2005, 02:53 PM
for the most part i understand the chalk length away rules, but what if the balls are frozen together, does this rule apply? anytime i've been informed about this rule there was never a stipulation if the balls are frozen together? i saw a tony drago shot where he had a frozen ob cb, and he shot without jacking up, all he really did was cut it thin and play safe, and then i saw allen hopkins in one of his tips at the champions of champions, where he had ob cb frozen together and he all but shot str8 at it and said that it was a legal shot because of how they where set up?

That shot is the 'other' 45 degrees, at least 45 degrees of cut. So a very thin cut on a ball frozen to the CB would be a 75 degree cut, which is OK under the rule because it is more than 45. This is also quite handy because you can take advantage of some throw to get additional directions.

Dave

DaveK
03-04-2005, 03:11 PM
So it's OK to hit the cue ball multiple times if elevated. My own feeling is that it's better to educate the players on what the balls are doing and train them to determine when douible hits occur, and get them to accept the rulings of referees when necessary. But I recognize that in some league situations, such a solution will never happen. I wonder if the people who made up the 45-degree rule are aware that it has almost no bearing on the occurence of a double hit. Also, I'd be willing to bet that many of the shots are played with less than 45 degrees of elevation.

How do you generally handle the situation when the balls are slightly more than a chalk apart?

Based on your comment about 'almost no bearing on the occurrence of a double hit', it seems that you say a straight shot on a close ball has the same chance of a double hit as a very thin cut on that same ball, given the same stroke. This does not feel at all correct to me. The difference in the likelihood of a double hit at 42 degrees of cut versus 48 degrees of cut would be much closer. But again, I can't see how you would say 'almost no bearing'. The vectors suggest otherwise, clearances and all .... If you are speaking of only the 45 degrees of elevation rule, you comment may be correct, but the rule has two options.

In a more perfect world the education would help, but I think the rule is to make the game less confrontational in these situations. If all games were refereed then the rule would be unnecessary.

I believe that the chance of a double hit increases as the CB and OB get closer. I also believe that calling some double hits is difficult (hence the guidelines for calling said infraction). Double hits take the form of 'obvious' through 'very subtle'. So, to make the game more reasonable when playing without a referee, the 45 degree rule is used. Does it make illegal hits legal ? Perhaps in some situations, but at least the ruling is clear and applies to both players. If the balls are a bit farther apart than a chalk cube, the opponent can call a foul. If the shooter disagrees, then we go to another thread and argue it there :)

Dave

pete lafond
03-04-2005, 03:13 PM
I believe the chalk thing was done to avoid arguments. This is to avoid a double hit. Your cue ball and object ball can be 1/2 the chalk distance apart and you can still play the shot with follow without a double hit, but it takes a very relaxed stroke. The rules for 8 ball on a bar box may not allow this even though it is perfectly legal.

DaveK
03-04-2005, 03:22 PM
That would be 1.16x10^8 angstroms! 1mm = 10^-3m and 1A = 10^-10m. Or you could say that an angstrom is an order of magnitude smaller than a nanometer. :D Just an FYI...lol.

Where were you 25 years ago when I was in electrical engineering school ?

Dave, cubit ? what's a cubit ? I used to know what a cubit is ...

Bob Jewett
03-04-2005, 03:24 PM
for the most part i understand the chalk length away rules, but what if the balls are frozen together, does this rule apply? anytime i've been informed about this rule there was never a stipulation if the balls are frozen together? i saw a tony drago shot where he had a frozen ob cb, and he shot without jacking up, all he really did was cut it thin and play safe, and then i saw allen hopkins in one of his tips at the champions of champions, where he had ob cb frozen together and he all but shot str8 at it and said that it was a legal shot because of how they where set up?
At pool there is a special rule that says you can shoot directly towards a ball that the cue ball is frozen to and use any normal stroke. This is a special rule for pool. At snooker (Tony Drago's usual game) you must never, ever shoot towards a ball the cue ball is frozen to. At carom billiards, you are never, ever permitted to shoot towards a ball frozen to the cue ball.

The rules for pool are on-line even if they are not perfectly clear. See the WPA or BCA websites.

Walt in VA
03-04-2005, 03:31 PM
for the most part i understand the chalk length away rules, but what if the balls are frozen together, does this rule apply? anytime i've been informed about this rule there was never a stipulation if the balls are frozen together? i saw a tony drago shot where he had a frozen ob cb, and he shot without jacking up, all he really did was cut it thin and play safe, and then i saw allen hopkins in one of his tips at the champions of champions, where he had ob cb frozen together and he all but shot str8 at it and said that it was a legal shot because of how they where set up?
If the CB/OB are frozen together, you can shoot straight through with a normal stroke without a foul - it's the same as hitting one ball, both will leave the cue tip together without a double hit.

Walt in VA

Rackin_Zack
03-04-2005, 03:34 PM
Where were you 25 years ago when I was in electrical engineering school ?

Dave, cubit ? what's a cubit ? I used to know what a cubit is ...

I didn't know what a cubit was, but I looked it up and it's 0.479280006403181m.

I'm a biochemistry major so I've had a lot of chemistry, biology, biochemistry and some physics where the angstroms and various metric conversions were pounded into my head...lol.

DaveK
03-04-2005, 03:44 PM
I didn't know what a cubit was, but I looked it up and it's 0.479280006403181m.

Wow, nice precision ! Note that a sacred cubit is a bit longer :)

Dave

Bob Jewett
03-04-2005, 03:53 PM
Based on your comment about 'almost no bearing on the occurrence of a double hit', it seems that you say a straight shot on a close ball has the same chance of a double hit as a very thin cut on that same ball, given the same stroke. ...
Not quite. But I will say that pretty much every time I see someone do the 45-degree thing, they get a double hit. If the rules are going to permit double hits, why not go whole hog and say any single stroke is OK, no matter how many times the cue ball is struck? I think the 45-degree rule is totally bogus although it does seem to work for one league.

As for cubit, google says it's the length from your elbow to the tip of your middle finger. Or maybe the same length on the foreman building the Pyramids. "Honest, Officer, I was just showing you my cubit."

cueman
03-04-2005, 08:53 PM
Where were you 25 years ago when I was in electrical engineering school ?

Dave, cubit ? what's a cubit ? I used to know what a cubit is ...
A cubit was an ancient measurement of approximately 18" that was calculated from the tip of your fingers to the tip of the elbow.

Rod
03-04-2005, 11:57 PM
Double hits are possible with the cue ball 6 inches away from the object ball! (Let alone a chalk cube's distance.)

A double hit can occur if the "stroke follow through" is more than the distance between the cue ball and the object ball.

Since a 6 inch follow through or more is common with many players, a cue ball 6 inches or less away from the object ball is in danger of a double hit.

The symptoms of a double hit are:
-The cue ball "immediately" follows the object ball.
-The cue ball closely follows the object ball.
-The cue ball does not "hesitate" or "stop" prior to following the object ball in the case of a follow shot.
-A "double click" sound can be heard when the balls are further apart (difficult to hear when balls are close together).

The symptoms of a single hit are:
- The cue ball stops.
- A single "click" sound is heard (if balls are very close together, a double click may sound like a single click).
- In the case of a follow shot, the cue ball briefly "stops" or "hesitates" prior to proceeding forward. (So just because the cue ball follows the object ball, this does not in itself mean that it was a double hit!)
- The cue ball follows further behind the object ball due to the delay caused by the brief "stop" or "hesitation".

Experiment with the above. Follow through longer than 6 inches with the cue ball 6 inches from the object ball and watch the double hit. Try single hit follow shots and watch the cue ball hesitate prior to proceeding forward.

You can hit directly at the cue ball when it is less than a chalk cubes distance from the object ball and have a good hit! It is called a "nip" shot....

How to shoot a perfect nip shot every time and avoid double hits...

It is simple. During a normal stroke, your arm can only move so far forward until it is at the end of the follow through of your stroke. So..... Begin your nip shot stroke with your hand fully forward - fully extended at the end of its stroke so that you can only stroke forward and additional 1/8 inch, or 1/4 inch or so. Your arm can't move any more forward since it is already all the way forward!

So before shooting a nip shot or a shot where the cue ball is 6 inches or less away from the cue ball, extend your arm fully forward or stand further back, then practice stroking to the side of the cue ball. Be sure that you will not stroke further past the cue ball more than the distance between the cue ball and object ball.

Note: There is also a nip follow shot and a nip draw shot.

(BTW - I will be out of town for a few weeks, so will not be able to respond to this thread for awhile....)

You can also have the balls an 1/8" apart using side english srtoke through the ball and leave the c/b spinning. It doesnt progress past the contact point. You can also draw it table lenght as well. The old chalk distance is only a guide line. In the end it takes someone knowledgable to know if it was a double hit as you pointed out in your post.

Rod

vagabond
03-05-2005, 06:59 AM
I saw that too and was always told that was a foul, even though Hopkins said that it wasn't?!

Hi,
Allen was talking about the rules Pro players use.In early 90s when Allen was the President of Mens professional Billiards association(MPBA) he published a rules book and this issue was addressed in that book.According to that it is not a foul.
Vagabond

DaveK
03-05-2005, 12:17 PM
I think the 45-degree rule is totally bogus although it does seem to work for one league.

As for cubit, google says it's the length from your elbow to the tip of your middle finger. Or maybe the same length on the foreman building the Pyramids. "Honest, Officer, I was just showing you my cubit."

Fair enough Bob, you are certainly entitled to your opinion and given your work with the rules of billards, it is not surprising. I like the rule for league with no ref's but would not think it appropriate to apply the rule in major money events, just like the shooter-rules rule would be a bad idea :)

A cubit is what gave God some frustration when questioned by Noah in a famous Bill Cosby monolog from a few decades back ... be careful it doesn't land you in the slammer !

Dave

Bob Jewett
03-06-2005, 05:15 PM
Hi,
Allen was talking about the rules Pro players use.In early 90s when Allen was the President of Mens professional Billiards association(MPBA) he published a rules book and this issue was addressed in that book.According to that it is not a foul.
Vagabond
Actually, under the current rules, you are permitted to shoot straight towards a frozen ball with any normal stroke. That was the shot originally described relative to Hopkins' comment. I believe that the rule used by the MPBA was substantially the same as the rule in use today.

Johnson
03-06-2005, 08:30 PM
is this shot legal withing the bca, vnea or apa rules?
________
Ocean View Condominium (http://pattayaluxurycondos.com)

Walt in VA
03-06-2005, 09:10 PM
is this shot legal withing the bca, vnea or apa rules?
BCA Rule 3.23 -
"FOULS BY DOUBLE HITS -
If the cue ball is touching the required object ball prior to the shot, the player may shoot toward it, providing that any normal stroke is employed...."

APA rules agree - not familiar with VNEA rules.

The rationale is that with slight (less than a chalk-width) separation, the CB will slow on impact with the OB and may be struck again by the cue tip with a normal stroke/follow-thru. If the CB/OB are frozen together, it's the same as hitting one ball; both will leave the tip together.

Walt in VA

mjantti
03-07-2005, 02:36 AM
Based on your comment about 'almost no bearing on the occurrence of a double hit', it seems that you say a straight shot on a close ball has the same chance of a double hit as a very thin cut on that same ball, given the same stroke. This does not feel at all correct to me. The difference in the likelihood of a double hit at 42 degrees of cut versus 48 degrees of cut would be much closer. But again, I can't see how you would say 'almost no bearing'. The vectors suggest otherwise, clearances and all .... If you are speaking of only the 45 degrees of elevation rule, you comment may be correct, but the rule has two options.

In a more perfect world the education would help, but I think the rule is to make the game less confrontational in these situations. If all games were refereed then the rule would be unnecessary.

I believe that the chance of a double hit increases as the CB and OB get closer. I also believe that calling some double hits is difficult (hence the guidelines for calling said infraction). Double hits take the form of 'obvious' through 'very subtle'. So, to make the game more reasonable when playing without a referee, the 45 degree rule is used. Does it make illegal hits legal ? Perhaps in some situations, but at least the ruling is clear and applies to both players. If the balls are a bit farther apart than a chalk cube, the opponent can call a foul. If the shooter disagrees, then we go to another thread and argue it there :)

Dave

I think the 45 degree "rule" is a joke. You can easily get a double hit on a 50 degree cut if you use outside english and very difficult to get a double hit when shooting a 40 degree cut with inside english. The shot direction isn't the borderline, it's the english you're shooting with.

mjantti
03-07-2005, 02:40 AM
At carom billiards, you are never, ever permitted to shoot towards a ball frozen to the cue ball.

Slightly off topic, in carom if a ball is frozen to the cueball, I think you have a choice of spotting the cueball and the object ball and the third ball remains in place. So the rules are forgiving, you aren't necessarily forced to kick at ball(s) in carom if you end up frozen to a ball.

Maybe someone with more 3C knowledge will share this rule with us ?

predator
03-07-2005, 03:06 AM
If the CB/OB are frozen together, you can shoot straight through with a normal stroke without a foul - it's the same as hitting one ball, both will leave the cue tip together without a double hit.

Walt in VA

Yes, but straight on? It is not the same as shooting at the cue ball twice the weight. You can play thin cut safety under severe (and even not so severe)angle no problem, but just smacking the ball straight on at zero degrees would result in a double hit no doubt. What if all 16 balls were frozen together? How can one avoid double hit then?

For a straight on frozen CB/OB shot you'd need extreme elevation of the cue. In that case you're still shooting towards the OB, but are avoiding the double hit.

Hope this makes sense...

mjantti
03-07-2005, 04:29 AM
Yes, but straight on? It is not the same as shooting at the cue ball twice the weight. You can play thin cut safety under severe (and even not so severe)angle no problem, but just smacking the ball straight on at zero degrees would result in a double hit no doubt. What if all 16 balls were frozen together? How can one avoid double hit then?

For a straight on frozen CB/OB shot you'd need extreme elevation of the cue. In that case you're still shooting towards the OB, but are avoiding the double hit.

Hope this makes sense...

From BCA website:

3.23 FOULS BY DOUBLE HITS
If the cue ball is touching the required object ball prior to the shot, the player may shoot toward it, providing that any normal stroke is employed. If the cue stick strikes the cue ball more than once on a shot, or if the cue stick is in contact with the cue ball when or after the cue ball contacts an object ball, the shot is a foul.

So, if the cueball is frozen to the object ball (must be declared frozen) you are allowed to hit it full in the face. This is an exception to the double hit rule. Actually, if the balls are frozen, the cuetip touches only once on the cueball.

Skeezicks
03-07-2005, 07:40 PM
Also, what about the fact that the cuetip will hit the cueball many times before the cueball's speed increases beyond that of the cue stick? You pullin' legs? This no happen, Rackin.

chefjeff
03-08-2005, 07:26 AM
[QUOTE=Bob Jewett]Not quite. But I will say that pretty much every time I see someone do the 45-degree thing, they get a double hit. If the rules are going to permit double hits, why not go whole hog and say any single stroke is OK, no matter how many times the cue ball is struck? I think the 45-degree rule is totally bogus although it does seem to work for one league.

QUOTE]

Having played on 7 different leagues for 25 years and having seen every argument possible about these situations, if there's gonna be a rule about this, then I've got to praise the 45 degree rule.

It doesn't require the average Joe to know the physics of the game (he doesn't want to know), and it makes the push through/double hit shot much more difficult.

It also makes the player consider what happens with a level stick vs. a jacked-up stick, which MAY help him learn some of the physics of the game, which MAY help him improve overall.

Before this rule, an amateur could just slam close balls and rearrange the table completely without penalty.This would always cause the better player to argue about the hit, with the resulting problems being discussed here.

Not perfect, but better than the way it was.

Personally, I'd like to have players be able to do whatever wizardry possible with their shots, as this would make the game more interesting and exciting for spectators.

Jeff Livingston

mjantti
03-08-2005, 07:32 AM
That is right, but u still need to hit it clean. You can still foul if you dont.

Yes, true. The fact that the cueball is frozen to the object ball doesn't rule out the possibility of a foul by double hitting the cueball. It's still possible to do, yet not easy :)

chefjeff
03-08-2005, 08:35 AM
A cubit was an ancient measurement of approximately 18" that was calculated from the tip of your fingers to the tip of the elbow.

I always thought a cuebit was the little pieces of wood I found on the pool room floor after a tragic loss. :p

Jeff Livingston