BHE- Pivot Point

Beware_of_Dawg

Beware_of_Dawg

..................
Silver Member
Heard alot about backhand english (BHE), and read enough to know it's all predicated on the pivot point of your particular shaft. I have experimented with some BHE with mixed results... I'd like to do a little more tinkering with it. I guess a good starting point would be to know where the pivot point on certain shafts is... or to know how one locates the PP themselves.

I have 4 shafts all with uni-loc joints (doubt that matters)

Predator Z Shaft, OB-1, Predator BK2, Standard Lucasi shaft (dont use it ever but if it has a "standard" PP I'd like to know what it is)

So anyone know where the PP is for these shafts or can you tell me exactly where I find it myself?

Maybe it would be useful to some other AZ'ers if you knew some other shafts and where the PP's are... List 'em if you know 'em.

big tnx.
~D4\/\/G~
 
HMmmmm.... perhaps talking about pool, important skills & technical issues is not worthy of discussion on the worlds largest billiard forum... lol.

SOOOOOOO....... Is anyone excited about the new Star Trek film coming out? Preview during the Superbowl looked epic...
 
at one time I think that Platinum Billiards had a chart showing the deflection and pivot points for all shafts and break cues...that was a while ago though, don't know if they still have it up.
 
Beware_of_Dawg said:
HMmmmm.... perhaps talking about pool, important skills & technical issues is not worthy of discussion on the worlds largest billiard forum... lol.

SOOOOOOO....... Is anyone excited about the new Star Trek film coming out? Preview during the Superbowl looked epic...
Click to expand...
I have seen numerous threads on BHE in the past. I am not familiar with it myself or maybe I am and don't know it. :)

BVal
 
Here's my quick take on BHE. Some shots really benefit from it. some it's incredible how much I end up missing because of it. Here is one of my favorite tests to see where your pivot point is on your cue's shaft. Place the OB/CB straight in at various distances from the pocket. Aim straight, then twist your back hand to give maximum left/right english. The ball will just about split the pocket and leave the CB spinning like a top. Now this is best acheived with a low deflection shaft.

I have never been too succesfull with this shot with my 314-2 (29") or my OB-1 (30"). I believe this was because my pivot point was in a different spot then where I was bridging. I was able to try a demo of the new OB-2 and I was trying this shot over and over and was splitting the pocket every time. Now this isn't a praise on OB-2 but a understanding that that shaft worked best for my bridge/pivot point.

And what is the pivot point. It is the point where the CB deflection is canceled out by the bridge point when english is used. Try hitting the CB or a striped ball to a spot (piece of chalk) on the end rail. Try different pivot points at maximum english (using BHE) and see when you are able to hit you mark. This is also fun to try with FHE, the same thing but move only your front hand. Both shots can be very affective in pool, but can also shoot you in the foot.

IMO

Hope this helps

TJ
 
BVal said:
I have seen numerous threads on BHE in the past. I am not familiar with it myself or maybe I am and don't know it. :)

BVal
Click to expand...

easiest way to describe it would be to tell you to set up your shot & bridge to hit the ball flush, straight in, center english. Now pivot your backhand (grip hand) a couple tips up/down/left/ or right without moving your bridge at all... and it may look like you are no longer in line to make the ball.... yet you do, dead nuts. and it gives you the desired english (and then some in alot of cases)... But it's all predicated on the pivot point of a shaft... if your bridge hand is above or below your shafts pivot point and you try this... results are... not so good, and inconsistant.
 
boba_fett23 said:
you could also try looking here...
http://billiards.colostate.edu/threads/cue.html
Click to expand...

Here's a procedure recommended by Colin Colenso for measuring natural pivot length:

Place OB about 6 inches from a corner pocket. Align CB in a straight line with this about 5-6 feet away. Align to pot straight, pivot and hit the shot near maximum speed to ensure insignificant swerve. Adjust bridge length until you consistantly have the CB hitting pretty much at the original aim.

It's pretty obvious when you're hitting this shot within 1/10th inch of center which allows you to narrow down the intrinsic pivot point to less than an inch. The CB would spin on the spot if the OB was hit about 1/20th inch off center. This is plenty of accuracy over 5-6 feet. Pretty much as accurate as one could hope to aim the initial pot.
Click to expand...

Im not entirely sure I understand. Someone got a diagram or can explain this better?
 
Beware_of_Dawg said:
Heard alot about backhand english (BHE), and read enough to know it's all predicated on the pivot point of your particular shaft. I have experimented with some BHE with mixed results... I'd like to do a little more tinkering with it. I guess a good starting point would be to know where the pivot point on certain shafts is... or to know how one locates the PP themselves.

I have 4 shafts all with uni-loc joints (doubt that matters)

Predator Z Shaft, OB-1, Predator BK2, Standard Lucasi shaft (dont use it ever but if it has a "standard" PP I'd like to know what it is)

So anyone know where the PP is for these shafts or can you tell me exactly where I find it myself?

Maybe it would be useful to some other AZ'ers if you knew some other shafts and where the PP's are... List 'em if you know 'em.

big tnx.
~D4\/\/G~
Click to expand...

Here's my post from December 2007 on how to find pivot points. The drawing that went with it isn't on the AZB server any more, but I'll try to remember to dig it up at home tonight and post it:


Simple Squirt Test
-----------------------

Here's a very simple way to find your shaft's Pivot Length.

1. Place any ball on the center spot of your table - this is your "object ball". Using a striped ball as your "cue ball" (with the stripe vertical and the stripe's edge pointed at the OB's edge as shown below), line up a straight shot for a corner pocket.

2. To start, separate the two balls by a measured distance that you guess is your shaft's Pivot Length minus 1 inch (so if you think your shaft might have a Pivot Length of 12", separate the balls by 11" to start).

3. Offset your tip so that it contacts the CB on the edge of the CB's stripe and the cue and the edge of the stripe are both aimed at the edge of the OB.

4. Stroke straight through the edge of the CB's stripe directly at the OB's edge - shoot the shot hard (without sacrificing accuracy) to eliminate swerve.

5. You'll miss the shot at first - that's a normal part of the test. When you miss, change the distance a measured amount and try again, aiming the cue and the edge of the CB's stripe at the OB's edge as before. If you got too much squirt, make the distance smaller. If you got too little squirt, make the distance greater.

6. When the shot goes in and the CB spins in place (more or less), the distance between the balls for that shot + 1 1/8" is your shaft's Pivot Length.

simple squirt test.jpg

NOTE FOR BHE USERS:
The Simple Squirt Test is like the "aim-and-pivot" squirt test except that it measures the Pivot Length for the actual tip/CB contact point rather than for the "center of shaft" offset. This might make the results more accurate and consistent than the aim-and-pivot results, but it means you have to add a small step when using the Pivot Length for applying aim-and-pivot ("backhhand") english: after pivoting the cue so the shaft's centerline points at the desired offset point, shift the stick slightly parallel so you'll actually hit the desired offset point with the tip.

pj
chgo
Click to expand...
 
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Finding the pivot point

I did not understand PJ's method (which could be perfectly correct), so I will offer this.

1. Chose a starting bridge length, say 7 inches. It doesn't matter, it will likely be "wrong."
2. With CB on the foot spot and using center ball, aim (but do not shoot)directly at a piece of chalk located in the center of the opposite short rail.
3. Now, keeping the bridge hand motionless, pivot the cue in your bridge hand moving only your grip hand (BHE) to apply 1 tip of left english.
4. Strike the cue ball and observe where it hits the far rail.
5. If you hit your target stop. Your initial bridge distance is you cue's natural pivot point distance.
6. If the CB hits the rail left of the target, repeat the process with a longer bridge.
7. If the CB hits the rail right of the target, try again with a shorter bridge.
8. Each time, chalk consistently, line up a straight center ball shot to the target and then pivot on the bridge hand using only BHE.
8. Keep adjusting until the CB hits the target. That length is the cue's natural pivot point, which may or may not be your usual bridge distance, or the appropriate bridge distance for a given shot.
9. If your cue's natural PP happens to be the same as the bridge distance you are using, you can use BHE alone without FHE adjustments. Since the appropriate bridge distance can vary, you may often have to make some adjustments.

Pivot points could be measured and posted whenever cues are advertised for sale. Maybe one day.
 
The easiest way to be sure is this.....

1.)The easiest way to be sure is to set up a shot. preferably a slight cut shot.

2.) Shoot it with no english.

3.) Find the best way to ensure you are duplicating your aim.

4.) Mark the table half a ball's length behind the OB in line with the shot, or whatever helps you to be sure you are aiming the same ass with NO side spin...

5.) aim at that spot.

6.) pivot from your bridge.

7.) shoot shot

8.) if it splits the pocket mark the shaft where your pivot point is for future reference. If it DOESN'T split the pocket, adjust bridge length and repeat.

9.) for soft shots with inside english, you'll want to adjust bridge length to about 75% of the pivot point's length



Just about every other shot will work without adjustment, except soft shots with outside english. For those shots aim a little opposite the side of the pocket of the spin you are placing on the CB


Jaden
 
Shaft said:
I did not understand PJ's method (which could be perfectly correct), so I will offer this.

1. Chose a starting bridge length, say 7 inches. It doesn't matter, it will likely be "wrong."
2. With CB on the foot spot and using center ball, aim (but do not shoot)directly at a piece of chalk located in the center of the opposite short rail.
3. Now, keeping the bridge hand motionless, pivot the cue in your bridge hand moving only your grip hand (BHE) to apply 1 tip of left english.
4. Strike the cue ball and observe where it hits the far rail.
5. If you hit your target stop. Your initial bridge distance is you cue's natural pivot point distance.
6. If the CB hits the rail left of the target, repeat the process with a longer bridge.
7. If the CB hits the rail right of the target, try again with a shorter bridge.
8. Each time, chalk consistently, line up a straight center ball shot to the target and then pivot on the bridge hand using only BHE.
8. Keep adjusting until the CB hits the target. That length is the cue's natural pivot point, which may or may not be your usual bridge distance, or the appropriate bridge distance for a given shot.
9. If your cue's natural PP happens to be the same as the bridge distance you are using, you can use BHE alone without FHE adjustments. Since the appropriate bridge distance can vary, you may often have to make some adjustments.

Pivot points could be measured and posted whenever cues are advertised for sale. Maybe one day.
Click to expand...

This is the "aim and pivot" method - this method and my "simple test" are equally valid, and both produce the same result by trial and error. This "aim and pivot" test requires you to move your bridge back and forth until it equals your pivot length while the "simple test" requires you to move the balls closer and farther apart until their distance equals the pivot length. Which method works best for you may be mostly a matter of preference.

pj
chgo
 
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Coping with changing bridge length

Jaden said:
1.)The easiest way to be sure is to set up a shot. preferably a slight cut shot.

2.) Shoot it with no english.

3.) Find the best way to ensure you are duplicating your aim.

4.) Mark the table half a ball's length behind the OB in line with the shot, or whatever helps you to be sure you are aiming the same ass with NO side spin...

5.) aim at that spot.

6.) pivot from your bridge.

7.) shoot shot

8.) if it splits the pocket mark the shaft where your pivot point is for future reference. If it DOESN'T split the pocket, adjust bridge length and repeat.

9.) for soft shots with inside english, you'll want to adjust bridge length to about 75% of the pivot point's length



Just about every other shot will work without adjustment, except soft shots with outside english. For those shots aim a little opposite the side of the pocket of the spin you are placing on the CB


Jaden
Click to expand...

This is another description of the "aim and pivot" method that Shaft described. With this method you move your bridge back and forth until you find the pivot point that works for your shaft, but it can be tricky trying to stroke shots accurately with different bridge lengths. To avoid that problem:

1. move your bridge hand to the new estimated pivot length

2. pivot your stick

3. before stroking the shot move your bridge back to its customary position

pj
chgo
 
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Patrick Johnson said:
1. Place any ball on the center spot of your table - this is your "object ball". Using a striped ball as your "cue ball" (with the stripe vertical and the stripe's edge pointed at the OB's edge as shown below), line up a straight shot for a corner pocket.

2. To start, separate the two balls by a measured distance that you guess is your shaft's Pivot Length minus 1 inch (so if you think your shaft might have a Pivot Length of 12", separate the balls by 11" to start).

3. Offset your tip so that it contacts the CB on the edge of the CB's stripe and the cue and the edge of the stripe are both aimed at the edge of the OB.

4. Stroke straight through the edge of the CB's stripe directly at the OB's edge - shoot the shot hard (without sacrificing accuracy) to eliminate swerve.

5. You'll miss the shot at first - that's a normal part of the test. When you miss, change the distance a measured amount and try again, aiming the cue and the edge of the CB's stripe at the OB's edge as before. If you got too much squirt, make the distance smaller. If you got too little squirt, make the distance greater.

6. When the shot goes in and the CB spins in place (more or less), the distance between the balls for that shot + 1 1/8" is your shaft's Pivot Length.
Click to expand...
As usual, your illustrations are a thing of beauty.

Just a suggestion. It's probably a good idea to wet the contact point on the cueball to reduce throw as much as possible. A degree or two can alter the results with some significance. Also, I would recommend completely ignoring what the cueball does after impact. Post-impact swerve, as well as throw if you're not greasing it up, can make it look like an off-center impact when it really isn't.

Patrick Johnson said:
NOTE FOR BHE USERS:
The Simple Squirt Test is like the "aim-and-pivot" squirt test except that it measures the Pivot Length for the actual tip/CB contact point rather than for the "center of shaft" offset. This might make the results more accurate and consistent than the aim-and-pivot results, but it means you have to add a small step when using the Pivot Length for applying aim-and-pivot ("backhhand") english: after pivoting the cue so the shaft's centerline points at the desired offset point, shift the stick slightly parallel so you'll actually hit the desired offset point with the tip.
Click to expand...
If so desired, you can convert the pivot point found by your method into the more standard one (aiming the center of the shaft at the apparent offset) by multiplying the distance between ball centers by 1.36 and then subtracting 1-1/8". (I bolded some words to distinguish it from your way of measuring things, which is valid for your pivot point.) The factor 1.36 is sort of an average and depends on the curvature of the tip, but it doesn't vary by too much with typical curvatures (nickel, dime, quarter). It's equal to:

f = (R + r)/R

where "R" is the ball radius (1.125") and "r" is the radius of tip curvature. Approximate values for "r" and thus "f" are:

dime: 11/32", f=1.31
nickel: 13/32", f=1.36
quarter: 15/32", f= 1.42

Jim
 
JAL:
As usual, your illustrations are a thing of beauty.
Click to expand...

Aw, shucks.

It's probably a good idea to wet the contact point on the cueball to reduce throw as much as possible.
Click to expand...

You'd have to be pretty lucky to guess which spot on the cueball will contact the object ball. Or are you suggesting getting the entire CB wet? :)

pj
chgo
 
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