Yes, it does clarify. I've been working on lengthening my bridge for both of those reasons (aiming and revealing stroke errors).
pj
chgo
How to Use Pivot Point Knowlege To Increase Error Margins
- Thread starter Colin Colenso
- Start date
pj
chgo
On the first question I'd say generally no. I can see little advantage in playing US pool games with a cue over 12.5mm ferrule and pure pivot point under 10 inches.... though, I'm sure some great players have managed it.
The second question is a really interesting one. The longer the bridge the higher resolution or increased margin of error a bridge V has. But the converse is that a longer bridge leads to a lower accuracy on CB hitting. So the + and - is up for debate.
If it weren't for the coincidence of longer pivot squirt cancellation effects, I'd tend on the side of shorter bridges, but as a convert the these error reduction methods, I tend toward favoring longer bridges to some extent in most situations. It's too complex to make a concrete rule on long being better than short... there are types of shots that have domain ranges that are preferential.
Colin
Colin, are you sure about this? Seems to me that with longer distances between CB and OB, swerve back to the original aim line is going to have more effect, so you'd want a longer bridge length with longer shots to get a little more deflection offline and allow for that swerve cancellation. This is how I've been doing it, and it works for me.
Now if you're talking about shots hit firmly enough to not have any swerve, I'd think that bridge length should be constant no matter the CB-OB distance.
I could be missing something, so feel free to educate me.
As an aside, when working with a pivot point bridge length with a closed bridge, make sure to closely examine your bridge and where exactly the cue pivots in it in both directions.
For example, with my closed bridge, pivoting to right english pivots at the base of my left index finger, making the bridge length effectively longer than pivoting with left english, which pivots more around the middle knuckle of my middle finger. That's about a 1.5" difference for me. So my personal mnemonic with a closed bridge is "righty tighty, lefty loosey" when estimating bridge length, so I use a slightly shorter (perceived) bridge length with right english shots.
-Ron
In my experience listening to pros and good amateurs talk about what they do, they're all pretty analytical, and at least try to verbalize all kinds of technical details. I'd say almost everyone who plays pool, from pros on down, talk about technical aspects of the game and how to play and make certain shots. Tons of the analysis you hear in pool rooms is BS, as I'm sure you would agree. But the idea that good players don't care about "technical stuff" is absolutely wrong, IMO. The real question is whether the technical stuff they talk about is accurate or not. People like Dr. Dave especially, and also Colin Colenso and Bob Jewett and Patrick Johnson and other posters here are trying to bring some accuracy to the technical aspects of the game that we all talk about already anyway.
And if pro pool had more money in it, I'm sure they would be doing what the pro golfers and tennis players (etc.) do: They'd all have nerdy coaches teaching them the technical mumbo-jumbo. The way pool is now, there's just not much of a well-established tradition of technical analysis yet like there is in other, more lucrative sports.
I'm not following all this talk about bringing the CB back in line from swerve. How do you guys hit the CB? Are you shooting shots at a 30 degree angle downward? Why in the world would swerve be so much of a concern? I shoot with an LD shaft so maybe this topic of all this pivoting is just something ppl with regular shafts have to worry about, but I haven't seen swerve of the CB be an issue unless I'm really jacked up on the CB. Possibly this discussion is something I'm so far away from that it seems like greek to me and 1 day I will understand it. It wouldn't be the first time but I can't for the life of me get a word of what you guys are talking about.
Hi Robin,
I must admit I started reading you post a few times and kinda got stuck in a loop on your first sentence the first few times.. either I'm too drunk or it needs an edit.
Upon getting past that intro, some nice points and I wish I could offer more insights but I really need to put together some good video with descriptions to show where the strength of pivoting lies and how one can be reasonably successful in the domains where SIT and CIT and swerve cause havoc.
Fact is, there's no easy way to play a medium speed long shot with OB 1+ foot from pocket, using max inside... or some equivalent, but there are ways to reduce guestimating some of the variables.
Cheers,
Colin
Any time you hit the cb off the vertical center, the cue will deflect, and the cb will squirt to the opposite direction of the english applied. How much it squirts depends on the endmass of the cue. This causes the cb to go at an angle from the actual straight line of the shot.
The cb now has horizontal rotation to it (side spin from the english applied). This rotation will eventually cause the cb to turn back towards the shot line.(swerve) At slow speeds with a lot of spin, the cb can actually turn back and go past the shot line. (think masse', but not that large of an effect). At higher speeds, the cb will go much farther before it starts to turn back towards the shot line.
This all happens so fast that it is almost impossible to see at normal speed with the naked eye. Yet, it happens on each shot with sidespin. On sidespin shots, the cb does not go in a straight line except at higher speeds.
What BHE (back hand english) does is simply compensate for the off angle the cb goes down when english is used. It also compensates for the swerve at the correct speeds for the distance involved.
LD shafts still have squirt and the cb still has swerve. But the squirt is not as large as with non-LD shafts. Check out Dr. Dave's site on squirt and swerve and you will understand it better. http://billiards.colostate.edu/bd_articles/index.html
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Almost positive Ron, but I can't be sure I've defined the parameters perfectly to make it easily understandable.Colin, are you sure about this? Seems to me that with longer distances between CB and OB, swerve back to the original aim line is going to have more effect, so you'd want a longer bridge length with longer shots to get a little more deflection offline and allow for that swerve cancellation. This is how I've been doing it, and it works for me.
Now if you're talking about shots hit firmly enough to not have any swerve, I'd think that bridge length should be constant no matter the CB-OB distance.
I could be missing something, so feel free to educate me.
As an aside, when working with a pivot point bridge length with a closed bridge, make sure to closely examine your bridge and where exactly the cue pivots in it in both directions.
For example, with my closed bridge, pivoting to right english pivots at the base of my left index finger, making the bridge length effectively longer than pivoting with left english, which pivots more around the middle knuckle of my middle finger. That's about a 1.5" difference for me. So my personal mnemonic with a closed bridge is "righty tighty, lefty loosey" when estimating bridge length, so I use a slightly shorter (perceived) bridge length with right english shots.
-Ron
On the shots I'm describing, they are reasonably close b/w CB and OB and reasonably firm, such that swerve is a minimal factor.
What I propose won't work very well on long shot where swerve plays a significant role.
Companies like Accurate promote ZERO throw cues, which is based on testing long shots where the CB swerves back to the original aim. Really crappy way of analyzing throw (the English term for squirt), but marketing is basically a box of chocolates and I don't think I've ever spotted a valuable physics insight into billiard sports from the UK. Pot like geniuses, understand the physics like drunkards.
That might color up the thread... come at me ancestral relatives
Colin
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I understand squirt and swerve but I don't perceive any amount of swerve that needs to be compensated for unless I masse` a ball. The only time I see a perceivable squirt that I need to compensate for is when I use inside english with a firmer stroke. I would say anything over a 4 speed. There must be something I'm missing here.
All you need to know is that everyone is wrong, SVB, Daz, and every other champion could elevate their game 5 balls by listening to Neil, Patrick Johnson and CJ Wiley. The pros we see on youtube and every major tournament are basically APA2's compared to the serious championship pedigree found by the posters of AZB forums. Seriously. You guys need to donate your genetic material to create the greatest cuesport athlete to ever walk the land. People will be telling stories of your creation for thousands of years, long after the civilization and cue sports we know have passed.
20 years from now I will be taking my child to the Natural Billiard Museum of Neil. At the entrance collecting tickets will be SVB, now retired after being put to rest by Neil. The tour guide will be Danny Diliberto, who cured the cause of aging.
It isn't that easy to see swerve on most shots, but it's undeniably there, even on shots that seem like your cue is level. To you it just looks a smaller amount of squirt.
You've just learned to adjust your aim subconsciously or to adjust your shot speed so swerve mostly cancels squirt (that would be why you notice squirt at higher speeds - because swerve is mostly eliminated).
pj
chgo
There's a simple way to avoid all the pain of trying to understand things that are just too complicated for you (you seem to get that a lot). The "universal ignore function" is activated by pushing a little button inside each ear like this:
pj <- singing optional
chgo
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I was talking about error reduction bridge length, which even you admitted to not knowing what it meant.
That's not quite correct, Neil. I made this drawing some years back to illustrate what happens. Left and right english do not create swerve. It is the axis running through the cue ball (pretend your cue is an axis passing through the cue ball) that matters -- the "3rd axis." When you elevate the butt of the cue, striking the cue ball causes a small amount of rotation about this axis. So what happens when you hit with right english with a little downward angle is that the cue ball squirts left due to the mass of the tip and then the downward spin from the tip (clockwise spin) causes the ball to curve, or swerve, back to the right.
2strong4u
Banned
I appreciate these sort of discussions about the physics of pool. Physics is the one science I never took.
I think that pool is a game of shot recognition, muscle memory and execution. If you put in the time and see what's happening on shots it's helpful. In the end you have to go out and execute what you know.
Nobody sitting over a shot thinking about swere, rotation, axis, deflection is going to play their best. If you practice correctly and stay in action, playing well is an unconscious execution of skill and not like taking the SATs.
I think that pool is a game of shot recognition, muscle memory and execution. If you put in the time and see what's happening on shots it's helpful. In the end you have to go out and execute what you know.
Nobody sitting over a shot thinking about swere, rotation, axis, deflection is going to play their best. If you practice correctly and stay in action, playing well is an unconscious execution of skill and not like taking the SATs.
Sorry dad, I'll go to my room now. Don't be so sensitive.
I'll admit i'm not the brightest bulb but I'm confused here. There are world champions who have a wide variety of strokes, bridge lengths and bridge types.
If the pivot point of a cue is so vital to the game how are these world class players so successful? Are they carefully selecting cues to match their pivot point?
If the pivot point of a cue is so vital to the game how are these world class players so successful? Are they carefully selecting cues to match their pivot point?