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tateuts
03-04-2004, 10:59 AM
Is this right? The author is saying that cues with stiff shafts cause the cue ball to squirt more than cues with whippy shafts.

On paper is may sound right, but my real-world experience is that whippy shafts squirt the cueball a lot more than (laterally) stiff shafts with a strong taper. What do you think?

Reflections on Deflection Part IV (http://www.azbilliards.com/rogerlong/skillschool17.cfm)


Chris

03-04-2004, 11:06 AM

Bob_Jewett
03-04-2004, 01:04 PM
<blockquote><font class="small">Quote tateuts:</font><hr> Is this right? The author is saying that cues with stiff shafts cause the cue ball to squirt more than cues with whippy shafts.
Reflections on Deflection Part IV (http://www.azbilliards.com/rogerlong/skillschool17.cfm) <hr /></blockquote>

I think that the most important factor in making a stick squirty is the mass in the front part of the shaft. Those who like physics and equations, and are interested in squirt, should read Ron Shepard's paper on the subject that is on the SFBA web site listed below (see "misc files") "Everything You Always Wanted to Know About Cue Ball Squirt, But Were Afraid to Ask"

As a matter of terminology, I think it's not useful to link all of the "not a perfectly straight line" phenomena in pool under the common heading of "deflection" but maybe it's a good way to stamp out its use as a (bad) synonym for squirt.

pooltchr
03-04-2004, 01:20 PM
I also like the link below by one of our regular posters to explain the differences between squirt, deflection, throw, and swerve.

http://www.duke.edu/~rulmer/poolterms.htm

tateuts
03-04-2004, 01:40 PM
<blockquote><font class="small">Quote Bob_Jewett:</font><hr>
I think that the most important factor in making a stick squirty is the mass in the front part of the shaft. Those who like physics and equations, and are interested in squirt, should read Ron Shepard's paper on the subject that is on the SFBA web site listed below (see "misc files") "Everything You Always Wanted to Know About Cue Ball Squirt, But Were Afraid to Ask"

As a matter of terminology, I think it's not useful to link all of the "not a perfectly straight line" phenomena in pool under the common heading of "deflection" but maybe it's a good way to stamp out its use as a (bad) synonym for squirt. <hr /></blockquote>

I read the paper. It's possible that because stiff cues usually have a strong taper, the relatively lower endmass is reducing the squirt rather than the stiffness of the cue.

Still the observations in the article "Reflections on Deflection" suggesting a whippy shaft deflects less appear to be wrong.

Chris

Troy
03-04-2004, 01:40 PM
And to further confuse the issue, I like the occasional use of "Back-Hand English" as a means to reduce squirt caused by deflection.

Troy

tateuts
03-04-2004, 02:00 PM
<blockquote><font class="small">Quote whitewolf:</font><hr>
I tend to agree with you 99%, the reason being that the Predator shaft is whippy as h*ll. Go figure. <hr /></blockquote>


Hi W.W.

My Predator shaft is really stiff - go figure.

Chris

SpiderMan
03-04-2004, 04:04 PM
<blockquote><font class="small">Quote tateuts:</font><hr> Is this right? The author is saying that cues with stiff shafts cause the cue ball to squirt more than cues with whippy shafts.
Reflections on Deflection Part IV (http://www.azbilliards.com/rogerlong/skillschool17.cfm)
Chris <hr /></blockquote>

No, he's wrong. AZ Billiards apparently does not read this stuff very closely before allowing their contributors to publish.

Like Bob, I'd refer you to the Ron Shepard treatise for a better technical explanation.

On an off-center hit, the cue tip deflects one direction and the cue ball deflects (or "squirts"" the other direction. The relative amounts of deflection depend on the relative masses of the two objects. The flexibility of the shaft, while not completely out of the equation, has a minor effect in comparison to the mass.

In the case of the cue tip, it's an "effective" mass that is considered. As you move back from the tip, that portion of the cue shaft moves less and less off line, therefore mass at points far removed from the tip has little effect.

Bottom line is the cue ball deflects less when the shaft deflects more. The shaft deflects more when it has low mass near the tip end. Being flexible has much less to do with it. The shaft resists deflection mainly because of the large force required to move the shaft sideways in a very small amount of time (high acceleration), and this required force is a linear function of the mass.

I believe Ron's paper mentions experiments that you can repeat to demonstrate the previously-metioned concepts. Measure cue-ball squirt using a particular cue, then tightly tape a weight near the tip end and measure again. You will get increased squirt because of the increased effective end mass of the cue, even though you have not affected the shaft's flexibility. You can then experiment with moving the weight away from the tip, and find that it makes less and less difference as you move it back toward the joint.

SpiderMan

phil in sofla
03-04-2004, 05:19 PM
Glad to see your disagreement with the Predator shaft being whippy, as that was completely confusing me.

Isn't the ply method of the construction, or splines, whatever is the best term for them, designed to stiffen the shaft? I know they hollow out the top of the shaft near the ferrule to lessen the mass near the tip as well, but I thought the construction was another part of their deflection decrease.

shark
03-04-2004, 05:42 PM
If you think about it if the cue stick is whippy it will (deflect) bend at contact absorbing some of the deflection from the cue ball. A stiff shaft wont bend, imparting all of the deflection on the cue ball.

tateuts
03-04-2004, 05:54 PM
<blockquote><font class="small">Quote shark:</font><hr> If you think about it if the cue stick is whippy it will (deflect) bend at contact absorbing some of the deflection from the cue ball. A stiff shaft wont bend, imparting all of the deflection on the cue ball. <hr /></blockquote>

Well that's what the author is saying. What I'm saying is - in reality it's not the case.

Chris

Cueless Joey
03-04-2004, 05:59 PM
<blockquote><font class="small">Quote shark:</font><hr> If you think about it if the cue stick is whippy it will (deflect) bend at contact absorbing some of the deflection from the cue ball. A stiff shaft wont bend, imparting all of the deflection on the cue ball. <hr /></blockquote>
I don't agree.
A whippy shaft will buckle way back away from the tip.
While it's buckling, it's tip will probably stay on the cueball a little longer then "catapult" the cueball to the opposite side of the english.
A stiff shaft doesn't mean it'll cause more cueball deflection. I've tried billiards shafts. They have very low deflection.
Flex point of the shaft has a great deal to do with deflection too imo.

justbrake
03-04-2004, 06:00 PM
I have a black dot shaft and I feel the deflexition of the shaft on long shots it feels like it bends quite a bit! but heres a link from another site for deflection
http://www.billiardworld.com/squirt.html

tateuts
03-04-2004, 06:00 PM
<blockquote><font class="small">Quote phil in sofla:</font><hr> Glad to see your disagreement with the Predator shaft being whippy, as that was completely confusing me.

Isn't the ply method of the construction, or splines, whatever is the best term for them, designed to stiffen the shaft? I know they hollow out the top of the shaft near the ferrule to lessen the mass near the tip as well, but I thought the construction was another part of their deflection decrease.

<hr /></blockquote>

It probably does have a lot to do with the way it's glued-up. But also, if you look at the taper of the shaft, they have achieved a nice cone shape from joint to tip. Yes, even the ferrule sems to be tapered.

I will also say that the laminated shaft idea makes it easier for them to be more consistent from shaft to shaft - I would think much less variation than solid lumber.

Chris

Cueless Joey
03-04-2004, 06:22 PM
<blockquote><font class="small">Quote tateuts:</font><hr> <blockquote><font class="small">Quote phil in sofla:</font><hr> Glad to see your disagreement with the Predator shaft being whippy, as that was completely confusing me.

Isn't the ply method of the construction, or splines, whatever is the best term for them, designed to stiffen the shaft? I know they hollow out the top of the shaft near the ferrule to lessen the mass near the tip as well, but I thought the construction was another part of their deflection decrease.

<hr /></blockquote>

It probably does have a lot to do with the way it's glued-up. But also, if you look at the taper of the shaft, they have achieved a nice cone shape from joint to tip. Yes, even the ferrule sems to be tapered.

I will also say that the laminated shaft idea makes it easier for them to be more consistent from shaft to shaft - I would think much less variation than solid lumber.

Chris <hr /></blockquote>
I don't know how 8 pieces of varying stiffness of wood can be more consistent than one piece of wood.
It'll probably be more stable but more consistent, I don't know. Consistency is probably not needed b/c the shaft is hollowed out at the end anyway.
Bill Hagan made low deflecting cues. Shooters who have shot with his cues love them. The shafts were not spliced.

boalt06
03-04-2004, 07:55 PM
Does your black dot shaft result in a lot of cue ball deflection?

Alfie
03-04-2004, 09:13 PM
<blockquote><font class="small">Quote justbrake:</font><hr> I have a black dot shaft and I feel the deflexition of the shaft on long shots it feels like it bends quite a bit! but heres a link from another site for deflection
http://www.billiardworld.com/squirt.html <hr /></blockquote>This page links to another

http://www.billiardworld.com/sticks.html

On this page the section on squirt reflects the conventional wisdom of the time, i.e., that a shaft's flexibility is the main determining factor of how much squirt it has. This has since been debunked.

JohnnyP
03-05-2004, 10:50 PM
I've had this cue since '67:
old cue (http://www.jandssafeguard.com/oldcue/both%20ends.jpg)

I used to use Scotch Brite and sand paper on it, so I've necked the shaft down a little. The ferrule has always been about 11.5mm.

It's pretty whippy, but has WAY less squirt than my Dufferin SP, or my wife's Cuetec. I try them once in a while, and they go right back into the case.