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Pacifist
03-01-2010, 05:10 PM
I have seen a lot of discussion on low deflection shafts. Many shafts claim to reduce deflection by 30% or more. My question is how much deflection does the average cue have?

Jal
03-02-2010, 04:30 AM
Approximately 2-1/2 to 3-degrees at about 75% of maximum tip offset, maximum tip offset being the miscue limit of one-half the cueball's radius away from center. By deflection, I'm assuming you mean cueball deflection, i.e., its deviation from the direction in which the cue is pointed. (It's a little less confusing when this is referred to as "squirt," as this distinguishes it from that other deflection, the bending and pushing off of the shaft itself.) If you want more info, you might want to read articles 28 and 21 (Feb. and Aug. 2008) by Dr. Dave Alciatore on this page:

http://billiards.colostate.edu/bd_articles/index.html

But feel free to ask or comment here, of course. Since this is your first post, and hopefully not the last, welcome to the forum!

Jim

cushioncrawler
03-02-2010, 03:13 PM
What i would like to see iz some tests and meazurements of what the Qtip duzz.
If u hit (try to hit) a Qball dead'center and dead'straight every cue bends (a sort of S'bend praps) and vibrates.
So, the Qtip allways trys to go left or right or something before it leevs the ball.
So, no cue can ever hit the Qball straight, nor without side -- but some cues will (here) be better than others.
This needs a name -- Wipe'Left or Wipe'Right might do.
Koz held in a certain way this moov'n'spin will allways be in a certain direktion -- due to imperfektions.
I suppoze that it would be possible to build a cue that had near'nuff zero Wipe -- but probly not at all strengths of shot.
But the worst cues for Wipe might be the so called low deflection cues.

doncartmill
03-04-2010, 01:47 AM
Dr Dave discusses a lot of this at this site
There used to be a site "PLatinum Billiards" that had a chart showing CB deflection/squirt, where data was taken on a table that had been stripped of cloth and an aluminium surface used
( this was to eliminate swerve from the mix ) I could find a "Platinum BIlliards" site ,but no way to get to the data they previously had available. Fortunately I had copied it.
OK guys I had to edit this. I spent an hour getting it to fit in tabular form and then when I submitted it.. It is all screwed up
You can still read it. You will see the shaft tested,dime or nickle tip curvature;CB deflection in (mm); (inches); Length of pivoy point in inches Deflection/Squirt was measured at 50 inches down table
with a 9 mm off set ( english )on the cue ball
Shaft tested Tip CB deflect Pivot Pt
curve (mm) (inch) (inches)
Predator Z dime 34.3 1.35 12
Predator 314 dime 36.1 1.42 11.3
Predator Break dime 37 1.46 11
Axiom dime 39.5 1.56 10.3
Action dime 40.1 1.58 10.1
Meucci Red Dot dime 40.1 1.58 10.1
5280 dime 40.7 1.6 9.9
Sierra dime 41 1.61 9.9
Cuetec Thunderbolt dime 41.7 1.64 9.7
Viking nickel 41.7 1.64 9.7
Sterling nickel 41.8 1.65 9.6
Falcon dime 42.9 1.69 9.4
McDermott dime 42.9 1.69 9.4
Mezz dime 42.9 1.69 9.4
Players dime 43.5 1.71 9.2
Sledgehammer J/B dime 43.5 1.71 9.2
Cuetec Vortex dime 43.8 1.73 9.1
Mali dime 43.8 1.73 9.1
Pechauer nickel 43.8 1.73 9.1
Scorpion J/B quarter 43.8 1.73 9.1
Blaze dime 43.9 1.73 9.1
Joss quarter 44.1 1.74 9.1
Cuetec SST nickel 44.3 1.74 9
Meucci Black Dot dime 44.4 1.75 9
Fury nickel 44.6 1.76 9
Lucasi dime 44.8 1.76 8.9
Schon nickel 44.8 1.76 8.9
Axiom J/B dime 46 1.81 8.7
Mezz Break quarter 47.8 1.88 8.3
Scorpion Break dime 51.4 2.02 7.6

doncartmill
03-04-2010, 09:49 AM
I wanted to note,that the best shaft caused a squirt of 1.35 inches wow,and the worst (excluding J/B cues) was the Schon w/ nickle tip curve at 1.76 inches. Now that is significant movement(squirt/CB deflection ) and with 0.41 diff between these two shafts,it stands to reason there would be a significant period of adjustment ,if you were to switch from a Schon to a Predator Z shaft,or visa versa. If you were using the BHE method and bridging at Pivot point ...these differences would be negated. Since ,however, it is the nature of the game and you will NOT always be able to bridge at the PP ,you will experience and have to adapt to the difference on these shots.

Pacifist
03-04-2010, 04:32 PM
Thanks for the replies. That answers my questions.

cushioncrawler
03-04-2010, 04:32 PM
Thanx for themz numbers.
I am thinking that theze are for a level cue, ie pure'squirt -- and i am wondering what the squirts would be when jacked'up the uzual amount -- and when jacked'up even moreso, ie for skrew -- ie there would be less squirt when jacked'up -- ie the lo'squirt cues would be even more different to the hi'squirt cues (i think).
I am thinking that the hardness of the tip would be important too -- ie more squirt if soft.

I am allso thinking that 9mm of cue'offset equals praps 7mm of kontakt'offset for the initial kontakt -- and this 7mm aint much -- 7mm/57mm = 12.2% = 1 in 8.1 -- a biggish kontakt'offset might be say 25%, ie double the 7mm -- ie allmost double the 9mm of cue'offset, ie about 17mm of cue'offset.

But, mainly, i am thinking that having a cue that matches your favorit pivot length, ie favorit bridge length, iz what really counts.

doncartmill
03-04-2010, 11:53 PM
This site discusses Pivot point cancelling squirt ,how to detirmine the natural PP of your cue.etc

acuerate
03-06-2010, 07:10 AM
I have some doubts about using a fixed pivot point to compensate for squirt ! Seems that in this post nobody discuss the different angle of squirt caused when you hit the cue ball centre, below centre or with top spin ! Using the pivot 'technique' might help for a centre shot with left or right hand side English, but if you play a draw shot with side english then the squirt will be much higher.

Pivot technique is only a guidance. In fact the only thing you do is 'aim to miss' ... that's all.
Use a low 'squirt' shaft is the easier option I guess.

Logically the reason why pool shafts have so much squirt is because they are completely oversized (just compare the size of the balls with tipsize of any other billiard sport).

Enjoy the game,

Johan

Jal
03-06-2010, 02:52 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: acuerate</div><div class="ubbcode-body">I have some doubts about using a fixed pivot point to compensate for squirt ! Seems that in this post nobody discuss the different angle of squirt caused when you hit the cue ball centre, below centre or with top spin ! Using the pivot 'technique' might help for a centre shot with left or right hand side English, but if you play a draw shot with side english then the squirt will be much higher.</div></div>
Ignoring subsequent swerve (mini-masse) of the object ball, the intrinsic squirt compensating pivot point is, practically speaking, the same, whether hitting with pure side or combined with draw or follow. But for those who <u>explicitly </u>pivot in order to simultaneously compensate for both squirt and swerve, I think your point is absolutely valid. Swerve is a much more difficult animal to deal with, since it varies with everything.

I guess it should also be mentioned that, in theory, the intrinsic pivot point location is different depending on how much tip offset is used: more offset equates to a touch longer pivot distance (i.e., less squirt than a linear increase with offset). But it isn't much, and given the sometimes wildly varying estimates of where the "average" pivot point might be, it's the least of our problems. /forums/images/%%GRAEMLIN_URL%%/smile.gif

Jim

dr_dave
03-06-2010, 04:05 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jal</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: acuerate</div><div class="ubbcode-body">I have some doubts about using a fixed pivot point to compensate for squirt ! Seems that in this post nobody discuss the different angle of squirt caused when you hit the cue ball centre, below centre or with top spin ! Using the pivot 'technique' might help for a centre shot with left or right hand side English, but if you play a draw shot with side english then the squirt will be much higher.</div></div>
Ignoring subsequent swerve (mini-masse) of the object ball, the intrinsic squirt compensating pivot point is, practically speaking, the same, whether hitting with pure side or combined with draw or follow. But for those who <u>explicitly </u>pivot in order to simultaneously compensate for both squirt and swerve, I think your point is absolutely valid. Swerve is a much more difficult animal to deal with, since it varies with everything.</div></div>Good point Jim. I think people often confuse squirt (CB deflection) with squerve (the combined effects of squirt and swerve). If people are curious, I have a good illustration and a complete summary of how squirt, swerve, and throw vary with everything here: