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Shaft
10-23-2007, 12:39 PM
I know I am contrarian, but I do not buy into the low-tip-mass=low-squirt theory. As long as the tip of the shaft is mechanically coupled to the rest of the cue, the tip transfers to the CB, through the bending modulus, almost all the rotational and linear inertia of the entire cue, even if the tip had "zero mass." The exception being, if by "low mass," you really mean "small diameter and therefore low bending modulus." There I would agree, but I think that would aggravate squirt, not help it. MHO.

If you disagree, that's fine. Until someone really quantifies stiffness and then correlates that to squirt, I will agree to disagree, because I could be wrong.

The real point of this post is that I am looking for who makes the stiffest shaft. I am going to buy one good cue, and I hate the feel of a whippy cue "twanging" in my hands after a solid hit.

Based on their laminated construction, I would guess the Meucci Black Dot flat-laminated or the OB1 radially-laminated shafts are stiff, but that is just a guess. Anyone know who makes the stiffest pro taper shaft?

On his video, Bob Meucci claims that flexibility is the key to low squirt. If that is true, why did they laminate the Black Dot shaft? In plywood, lamination generaly makes wood stiffer, not more flexible. (Unlike plywood, The black dot and OB1 use parallel plys, so I realize that might make a difference.)

Regards to all fellow fans of the game,

Bob_Jewett
10-23-2007, 12:46 PM
<blockquote><font class="small">Quote Shaft:</font><hr> I know I am contrarian, but I do not buy into the low-tip-mass=low-squirt theory. ... <hr /></blockquote>
I think you may change your mind if you read Ron Shepard's paper on squirt and view the high-speed videos of what happens with an off-center hit. Also, Mike Page has done a very interesting video of squirt with modified end-mass that's a must see. Look for FargoBilliards on www.youtube.com. (http://www.youtube.com.)

Ron's paper is item 10 at http://www.sfbilliards.com/misc.htm

Of course stiffness comes in somehow to help determine the effective end-mass, but I have never seen a good demo of this. I think it is a hard demo to do.

Ralph_Kramden
10-23-2007, 04:28 PM
I looked at the Youtube videos and the vise grips attached to the end of the shaft. It's kinda' like a collision between a pickup truck and a locomotive. Whether the truck hits the train or the train hits the truck, it is the one with the lesser mass thst moves over.

If a shaft with more mass on the tip end makes the cueball 'squirt' more what happens with a low mass, low squirt cue?
I think that both solid tip and hollow tip cues would deliver the same amount of force on a ball hit dead center. If the ball is hit with side english the force is somewhat deflected. The cueball squirts less with a low squirt cue because the cue must be what is deflecting like the truck off the locomotive.

Am I wrong in my thinking? If the direct force is off to one side, either the cueball or the cue with a lighter mass tip must 'squirt' somewhat to the side.

Players use squirt with sidespin to gain shape. I say beware the player who can't run 3 balls but.. when faced with a straight in shot can come off 2 rails for shape a the money ball.

1hit1der
10-23-2007, 07:58 PM
Shafts that incorporate non-wood materials are often stiffer, such as the Cuetec Vortex and Thunderbolt as well as the McDermott Intimidator series.

Aside from that, the laminated shafts should have anisotropic stiffness and bending moduli. I heard with the Meucci's, you're supposed to shoot with the dot up, facing away from the table. I'm not sure which orientation this puts the plies, but my guess is that they'd be running perpendicular to the table if the shaft is meant to minimize stiffness.

A lot of jump/break sticks are designed to have stiff shafts. If you really want, go for one of those and put a leather tip of preferred hardness on it.

Ralph_Kramden
10-24-2007, 04:32 PM
Shafts on most cues, but not all, will bend eaisier when you apply pressure to one the side of the shaft and will have less bend on the opposite side. Place your cue on the table and hold the butt end slightly off the surface. Put pressure on the shaft to see how it bends. Turn it over 180 degrees and do the same thing. Do it all around the shaft diameter.

If the shaft has a tendency to have a stiffer bend in one direction you can put a dot on the cue so you can turn it to the same spot any time you need to hit a long drawshot.

I don't think it makes much difference as far as 'squirt' goes.. (I like that word) but it may help you draw the ball or keep you from scooping under if you have a bridge that is farther from the cueball. The main reason the ball jumps on a draw is a bridge hand that isn't solid under the shaft and a cue tip that defelects downward toward the table.

The next time you hit a jumped ball when you try to draw look at the cloth. There will be a chalk mark where the shaft was pinched between the cueball and the table.

sygfrid
10-24-2007, 05:09 PM
You may want to try SUGARTREE Custom Cues by Eric Crisp. You might find what you're looking for in a solid 1-pc high-quality shaft.

I found mine with my custom cue. Unfortunately, the cue maker already decided to retire

dr_dave
10-24-2007, 05:38 PM
<blockquote><font class="small">Quote Shaft:</font><hr> I know I am contrarian, but I do not buy into the low-tip-mass=low-squirt theory. As long as the tip of the shaft is mechanically coupled to the rest of the cue, the tip transfers to the CB, through the bending modulus, almost all the rotational and linear inertia of the entire cue, even if the tip had "zero mass." The exception being, if by "low mass," you really mean "small diameter and therefore low bending modulus." There I would agree, but I think that would aggravate squirt, not help it. MHO.

If you disagree, that's fine. Until someone really quantifies stiffness and then correlates that to squirt, I will agree to disagree, because I could be wrong.<hr /></blockquote>Shaft,

Bob provided links to some good resources. Here are some more:

- my August '07 article (http://billiards.colostate.edu/bd_articles/2007/aug07.pdf) with illustrations, photos, and video links explaining the physics behind squirt.

- TP A.31 (http://billiards.colostate.edu/technical_proofs/new/TP_A-31.pdf), which presents the math and physics behind squirt.

- my recent series of articles (http://billiards.colostate.edu/bd_articles/index.html) dealing with squirt.

As you point out, and as I point out in the articles and in the analysis, end-mass and lateral stiffness are related. Generally, a stiffer shaft will be heavier at the end. Also, the transverse shock wave travels faster in a stiffer shaft, invoking more end mass.

As Bob has pointed out, the theory and several experiments from several people and the low-squirt shaft industry demonstrates that lower end-mass creates less squirt. The force created by lateral deflection of the shaft is much smaller than the inertial impulsive forces created during tip contact.

Regards,
Dave

mikepage
10-27-2007, 01:45 PM
<blockquote><font class="small">Quote Shaft:</font><hr> I know I am contrarian, but [...]

If you disagree, that's fine. Until someone really quantifies stiffness and then correlates that to squirt, I will agree to disagree, because I could be wrong.
[...] <hr /></blockquote>

You seem a little tough to convince. This shaft had the same squirt pre and post surgery and now has the same squirt in different radial directions.
http://myweb.cableone.net/fargopage/wmcfh3.jpg

Shaft
10-28-2007, 06:47 PM
Thanks to everyone who replied, especially Bob Jewett and Dr. Dave Alciatore who posted the links. The vice grip video has convinced me.
Thanks also to MikePage. I am not sure how that cue could hit anything w/o breaking, but I take your word for it. Thanks for posting the picture.

dr_dave
10-29-2007, 08:23 AM
You're welcome. I'm also glad we now have Mike's video to refer to in the future when other people bring up this perennial topic.

Regards,
Dave

<blockquote><font class="small">Quote Shaft:</font><hr> Thanks to everyone who replied, especially Bob Jewett and Dr. Dave Alciatore who posted the links. The vice grip video has convinced me.
Thanks also to MikePage. I am not sure how that cue could hit anything w/o breaking, but I take your word for it. Thanks for posting the picture.<hr /></blockquote>