Billy_Bob said:
Hi Billy,
How do you test?I'd like to see the formula for pivot point.
Thanks RJ
What's your cue's Pivot Point?
- Thread starter Colin Colenso
- Start date
Hi Billy,
How do you test?I'd like to see the formula for pivot point.
Thanks RJ
Hi Mike,mikepage said:
Are you quite sure about those pivot point lengths?
The test I read that Bob Jewett recommend is basically the same but requires aiming at a OB to pot a straight shot. Whichever way, it shouldn't take many shots to narrow the pivot point down to a couple of inches, so long as initial alignment is reasonably accurate.
I played 95% my pool using 1 and 7/8" CB which with hindsight must have defelcted considerably more that 2 and 1/4" CB's which are 50% heavier. I used about a 9.5mm cue and even though I knew nothing about BHE at the time, I believe the pivot point of my cue under those conditions roughly corresponded to my bridge length, allowing me to control side english shots quite well using some degree of hook and throw.
So at the moment, I find it hard to see the advantage of using a cue with a pivot point much longer that my bridge length. Such a cue would cause me to miss if I don't hit the CB exactly where I am aiming, whereas a cue with a shorter pivot point will effectively cancel out cueing errors.
I would appreciate your thoughts and experiences on this matter of preference.
Colin
Here's how Platinum billiards describes pivot points. Read about it here:
https://www.platinumbilliards.com/rating_about_pivotpoints.php?sid=292d761d90b21dd07c8e1baa9596ebe0
Here's what they say:
About “Pivot Points”
Each shaft has its own “pivot point” which is directly determined by the amount of cue ball deflection or “squirt” it produces. The calculated pivot point for each shaft is given in the chart as measured from the front of the tip. If you bridge exactly at a shaft’s pivot point and hold your bridge very steady, you can pivot the cue by moving your back hand and no matter where you strike the cue ball it will track off on the same line as if you struck dead center. Pivot points are interesting and may be useful but the player must also consider “swerve” and “throw”. Swerve is the tendency of the cue ball to curve slightly in the direction of the applied sidespin, like a mild form of masse. Throw is caused by the friction between the cue ball and the object ball and is much stronger than most realize – for example, if you shoot a straight in shot firmly with left spin and hit the back of the pocket, if a snapshot could be taken at the moment the cue ball contacts the object ball you would see that the balls are actually aligned significantly to the left of the center of the pocket. There is a popular “pivot point test” that uses this sort of straight shot to determine pivot points but because the throw effect was not considered people have been getting wildly inaccurate results. The pivot points given in our chart are calculated directly from the actual measured cue ball deflection produced by each shaft and are correct.
Basicaly what Plantinum Billiards is saying in the above info, is that there is a specific bridge hand distance (pivot point) that's best for each individual cue cue when appying backhand english.They also explain in the above info as to why people were getting "wildly innaccurate results" with a populiar pivot point test that is out there.
Platinum Billiards also says on there website that they used a robot to do there testing, so human error is not a factor.
here's some info on their testing practices:
HOW AND WHAT WE TEST
We ask the question “which shaft deflects least?” because the butt of the cue has little effect on cue ball deflection. However, shafts are generally tested on the same brand of butt and the test weight for all is kept close to 19 ounces. All shafts are tested as sold by the manufacturer including tip type and tip curvature as noted. All tests are performed using a robot which makes precisely the same stroke with each cue, and for this test the machine is set to produce cue ball speeds of around 15mph. A series of four shots is made with each cue and the resulting cue ball deflection is recorded on a target 50” away which is exactly the distance between the foot string and the head spot on a 4 ½ x 9 pool table. The four shots are 6mm (about ¼”) and 12mm left of center, and 6mm and 12mm right of center, and these offsets are measured from the center of the cue ball to the center of the shaft. The actual cue ball deflection produced by each shot is measured and the average for the series is given in the chart below in millimeters and inches.
RJ
https://www.platinumbilliards.com/rating_about_pivotpoints.php?sid=292d761d90b21dd07c8e1baa9596ebe0
Here's what they say:
About “Pivot Points”
Each shaft has its own “pivot point” which is directly determined by the amount of cue ball deflection or “squirt” it produces. The calculated pivot point for each shaft is given in the chart as measured from the front of the tip. If you bridge exactly at a shaft’s pivot point and hold your bridge very steady, you can pivot the cue by moving your back hand and no matter where you strike the cue ball it will track off on the same line as if you struck dead center. Pivot points are interesting and may be useful but the player must also consider “swerve” and “throw”. Swerve is the tendency of the cue ball to curve slightly in the direction of the applied sidespin, like a mild form of masse. Throw is caused by the friction between the cue ball and the object ball and is much stronger than most realize – for example, if you shoot a straight in shot firmly with left spin and hit the back of the pocket, if a snapshot could be taken at the moment the cue ball contacts the object ball you would see that the balls are actually aligned significantly to the left of the center of the pocket. There is a popular “pivot point test” that uses this sort of straight shot to determine pivot points but because the throw effect was not considered people have been getting wildly inaccurate results. The pivot points given in our chart are calculated directly from the actual measured cue ball deflection produced by each shaft and are correct.
Basicaly what Plantinum Billiards is saying in the above info, is that there is a specific bridge hand distance (pivot point) that's best for each individual cue cue when appying backhand english.They also explain in the above info as to why people were getting "wildly innaccurate results" with a populiar pivot point test that is out there.
Platinum Billiards also says on there website that they used a robot to do there testing, so human error is not a factor.
here's some info on their testing practices:
HOW AND WHAT WE TEST
We ask the question “which shaft deflects least?” because the butt of the cue has little effect on cue ball deflection. However, shafts are generally tested on the same brand of butt and the test weight for all is kept close to 19 ounces. All shafts are tested as sold by the manufacturer including tip type and tip curvature as noted. All tests are performed using a robot which makes precisely the same stroke with each cue, and for this test the machine is set to produce cue ball speeds of around 15mph. A series of four shots is made with each cue and the resulting cue ball deflection is recorded on a target 50” away which is exactly the distance between the foot string and the head spot on a 4 ½ x 9 pool table. The four shots are 6mm (about ¼”) and 12mm left of center, and 6mm and 12mm right of center, and these offsets are measured from the center of the cue ball to the center of the shaft. The actual cue ball deflection produced by each shot is measured and the average for the series is given in the chart below in millimeters and inches.
RJ
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Colin Colenso said:
I think it's important when doing Bob Jewett's test that you *not* aim to pocket the object ball. Line it up for some random spot on a rail. I think having the pocket there encourages us to unwittingly do what is necessary to pocket the ball, and that's a bad thing here. When you do Bob's test, you don't concern yourself at all with what the object ball does, only what the cueball does. There's a twofold purpose of the object ball in Bob's test; first, it provides a sensitive measure of which side of "full" the cueball it hitting on. That is, even if the cueball is only a half millimeter to the right of full, an amount otherwise hard to detect, it will drift to the right after hitting the object ball, and that's what you're looking for. Second, because the object ball is close to the cueball (a diamond or so), swerve does not have a chance to contaminate the measurement.
Here's a test for anyone who thinks they have a cue with a pp below 11 inches. Set up a ball six inches from one side pocket and shoot it into the other side pocket. On a 9 foot table, the ball is travelling 44 inches. On all shots, aim the stick directly for the center of the pocket. For five inch pockets, you will have two inches to spare with a half inch of english. So if the cueball squirts more than two inches over the 44 inches of travel, you will miss the pocket.
An 11 inch pivot point means that if you hit with a half inch offset, the cueball will veer off by a half inch for every 11 inches of travel. So for sticks with pps over 11 inches, the ball will be pocketed. And for sticks with pivot points below 11 inches, the pocket will be missed (with a half inch of english). I cannot miss the pocket with any of my sticks except for the Miz Cue from Hell, which misses every time.
mike page
fargo
No info after that page it seems.recoveryjones said:
I've never come across a cue website that can explain their claims or theoroes properly. Clearly they aim to appeal to the simple minded with specious statements and claims.
Are cuemakers really any more than a combination of woodworker, marketer and artist?
mikepage said:
Thanks for clarifying things with your above post.
Obviously the cue pivot point you are talking about is entirley different from the one Platinum Billiards is talking about. They are talking about bridge hand distance from the cue ball.
Their bridge hand placement ranges from 7.6 inches to 12.8 inches which is totally realistic and acceptable.You are talking about an entirley different pivot point test which doesn't include bridge hand placement as your pivot point measurement.
If it did, I would love to see you shoot with your Schuler and your bridge hand located 30 inches away from the cueball..LOL.
RJ
.......apples and oranges
Billy_Bob said:
There is a test somewhere to determine the ideal bridge length for your cue where aim and pivot is concerned.If I can find it, I'll post it. No need to buy a special cue.
RJ
Mike,mikepage said:
The side pocket test explanation you gave seems to be nothing like what I have explained as how to determine the pivot point.
The pivot point is the length of bridge required such that pivoting the back hand to hit the CB with a 1/2" offset, or whatever offset results in the CB still following the original line.
I have never seen a cue that would miss the side pocket using the test you describe. Even a rack cue with a 5" pivot point with an 11" bridge with left side would travel to the right of the original line by about 1/2" over 44 inches I estimate.
RJ,recoveryjones said:
The test that I find to be quick and easy is to place the CB on the head spot and aim center ball to the middle of the end rail. Place chalk on the middle of that rail as a guide.
STart with bridge of 4 inches, pivot for left hand side english about 1/and 1/2 tips and hit firm. The CB should go to the left of the chalk with most cues.
Do the same from 6, 8, 10, 12, 14, 16, 18 inches. You'll notice a progression of the CB hitting the rail more to the right as you lengthen the bridge. For example, at 18" bridge length the squirt will be greater than the angle change of the cue, so the CB will hit to the right of the target.
You'll quickly establish the length where the angle of the cue and squirt equal out such the the CB hits at the chalk spot (on the line of the original aim).
Colin Colenso said:
thanks Colin,
that seems like a real sensible and realistic test and I like it.
One problem:
Hitting 1 and 1/2 tips(left or Right) of english over and over with absolute presicion is humanly difficult for a lotof people to do. That's why I like Platinim Billiards use of a Robot for their calculations.I'm hitting straighter than ever before, so I'll give it a go.
RJ
You'll find it won't matter if you hit 1/2 tip or 2 tips off center. You'll still find the pivot point and and this point the CB will go straight no matter what amount of english you use, left or right.recoveryjones said:
Colin Colenso said:
My shooting cues are right about 11". The shortest pivot point I've had on a normal cue was Cuetech, which was right around 6-7". That was entirely too short for me.
I like the longer bridge for most game. I also like the length for developing more power with less effort.
FRed
Quote:
Originally Posted by recoveryjones
Here's a link that shows the pivot point for several cues:
http://www.platinumbilliards.com/rating_deflect.php
RJ
Hi Fred,
I just read your last three posts(about pivot points) and I'm left a little confused. In the above quote you mention 30+ range pivot point. Yet in your two posts previous to this one you mention that none of the pivot points are over 15.
Here's your quote in the post prior to this one:
Quote:
"Hmmm... not one of my normal cues has a pivot point above 15". Most of my cues fall right at that 11-12" mark.
Fred
Here's your quote in the post prior to the one above
Quote:
My shooting cues are right about 11". The shortest pivot point I've had on a normal cue was Cuetech, which was right around 6-7". That was entirely too short for me.
I like the longer bridge for most game. I also like the length for developing more power with less effort.
Fred
In Summary:
In one case your talking about everything under 15 and saying that your cues(pivot points) are between 6-12 inches.
In another post you are talking about 30+???
I guess you are talking bridge lengths(6-12) in the first instance and something else (a test result of some kind??) for the 30+ number.
I can't understand why you don't understand Platinum Billiards pivot points for ideal bridge lengths from the cue ball.They list very realistic bridge lenghts between 7.6 inches to 12.8 inches.What's so mis -understandable about realistic bridge lengths like that?
No doubt as mentioned before (in this thread) people are talking about to entirley different pivot points.With the smaller numbers (6-12) people are talking about ideal pivot point bridge lengths and the other pivot point(higher number like 30+) are for some deflection test.
With all this mentioned, Platinum Billiards(bridge length pivot point) numbers are totally understandable.
RJ
Originally Posted by recoveryjones
Here's a link that shows the pivot point for several cues:
http://www.platinumbilliards.com/rating_deflect.php
RJ
Cornerman said:
Hi Fred,
I just read your last three posts(about pivot points) and I'm left a little confused. In the above quote you mention 30+ range pivot point. Yet in your two posts previous to this one you mention that none of the pivot points are over 15.
Here's your quote in the post prior to this one:
Quote:
"Hmmm... not one of my normal cues has a pivot point above 15". Most of my cues fall right at that 11-12" mark.
Fred
Here's your quote in the post prior to the one above
Quote:
My shooting cues are right about 11". The shortest pivot point I've had on a normal cue was Cuetech, which was right around 6-7". That was entirely too short for me.
I like the longer bridge for most game. I also like the length for developing more power with less effort.
Fred
In Summary:
In one case your talking about everything under 15 and saying that your cues(pivot points) are between 6-12 inches.
In another post you are talking about 30+???
I guess you are talking bridge lengths(6-12) in the first instance and something else (a test result of some kind??) for the 30+ number.
I can't understand why you don't understand Platinum Billiards pivot points for ideal bridge lengths from the cue ball.They list very realistic bridge lenghts between 7.6 inches to 12.8 inches.What's so mis -understandable about realistic bridge lengths like that?
No doubt as mentioned before (in this thread) people are talking about to entirley different pivot points.With the smaller numbers (6-12) people are talking about ideal pivot point bridge lengths and the other pivot point(higher number like 30+) are for some deflection test.
With all this mentioned, Platinum Billiards(bridge length pivot point) numbers are totally understandable.
RJ
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recoveryjones said:
No it's not apples and oranges. It's the same thing. A cues pivot point is a property of the cue, like its length, weight, and balance point. It has nothing to do with where you bridge. However, if I *chose* to bridge at 30 inches with my Schuler, then the cueball would go in the same initial direction regardless of where the tip struck the ball.
mike page
fargo