ElCorazonFrio
Banned
Learn some basic physical principles. There will be bending of the broomstick, it will be extremely small.
Degrees Of Deflection
- Thread starter Tennesseejoe
- Start date
Learn some basic physical principles. There will be bending of the broomstick, it will be extremely small.
ElCorazonFrio
Banned
The OB site is saying what I said. The ob site is saying what you already know from years of living on this planet, every movement which you make is governed by the same physics.
Yes, because the cueball has mass, it has inertia. Because the cueball has inertia, it creates a force when hit with a cuestick. If the force has a left or right component due to hitting off center, then the force has to have an equal and opposite reactionary force.
Some guy named after a fruit-filled cookie explained this in the late 17th century. https://en.wikipedia.org/wiki/Newton's_laws_of_motion
I can't tell if we're saying the same thing or not.
The CB's rotation from an off center hit pushes the cue stick's mass to the side and the cue stick's inertia (resistance to movement) causes the CB's rotation to push itself in the opposite direction (squirt).
Yes, we agree on that.
This is all true, but all you've said is the CB goes farther when hit harder - and of course that's true of any shot with or without squirt. The "amount" of squirt means the angle of squirt because that's what changes from shaft to shaft.
pj
chgo
Last edited:
I design products and my implementation of physics is peer reviewed by The Analysis Department who have Doctorate's Degrees in physics to assure that my designs have sufficient Margins of Safety.
With that said to the first part.
The bending will be extremely small as you said and was my hyperbolic point. I thought that example my would be obvious to most readers except for pedants..
I wanted to express that a large wooden dowel is more rigid than a normal or a low deflection shaft and would produce a more visible squirt.
View attachment 392303
0014" deflection if it is a 1.13" diameter broomstick...negligible.
Perhaps I should have said an alumina dowel with a radius on the striking tip.
Be well
ElCorazonFrio
Banned
I think we are almost on the same page, but you are talking about squirt and I am trying to address the people who have said that deflection (of the shaft) does not change depending on how hard the cueball is struck.
ElCorazonFrio
Banned
You say pedant, I say engineer.
OK, I suppose shaft deflection changes with stroke speed, but that doesn't have much (or anything) to do with the shot's outcome.
pj
chgo
you're wrong p.j.
The cb's mass does NOT push the cue to the opposite side. Because during a non miscue contact,there is friction, it flexes the shaft in the opposite direction.
Once contact ceases, the flexion built up in the shaft during contact causes it to flex in the opposite direction as a reaction to the pent up forces in the shaft.
Jaden
The cb's mass does NOT push the cue to the opposite side. Because during a non miscue contact,there is friction, it flexes the shaft in the opposite direction.
Once contact ceases, the flexion built up in the shaft during contact causes it to flex in the opposite direction as a reaction to the pent up forces in the shaft.
Jaden
Actually, yes, it does. As I said, the CB's rotation pushes the cue stick's mass to the side, or to put it another way, the CB's rotating mass pushes the stick to the side.
If you're suggesting that the stick springing back from being flexed is what causes squirt, you're mistaken. In fact, in most cases the stick continues to flex in the same direction for a brief moment after contact before springing back. It's the stick's mass (not its stiffness) resisting the CB's sideways force (inertia) that causes the CB to push itself offline.
It's like two people on roller skates facing each other (A & B) and A pushes B away. They'll both roll backwards, B from being pushed and A from B's resistance to being pushed (inertia).
pj
chgo
I'm saying that the differential in mass between the cueball and shaft endmass causes an off center hit to flex the shaft during contact toward the greater mass of the center of the cueball, so the shaft is actually pointing in the direction the cueball travels when contact ceases. When friction is overcome and the tip starts to slip, then the built up flexion cause the shaft to travel away from the cueball.
This IS meted out in high speed video.
Jaden
Last edited:
Hi,
I concur and contend that the end of the cue flexes or bends away as does ElCorazonFrio, an engineer, and is a component of the resultant squirt angle.
High speed cameras show the vibration of the cue shaft at during and after the contact with the CB.
Be well
Last edited:
The aforementioned .0013" (~diameter of a hair) of deflection is another exaggeration (~worse case) for I entered the approximate mass of the cue ball (CB} into the calculator impacting the end of the dowel like the end of a diving board from above with the force on the dowel being the CB mass.
The .0013" defection of the dowel will be much less when the tip impacts the CB at a glancing angle, without miscueing, and only a fraction of the mass of the CB is acting on the side and (now) the tip of the dowel.
The deflection of a solid .50” diameter cue shaft could be 10 times that or .013” and there is more deflection on a LD hollowed out cue end which could be 10X that or ~ .125” or 1/8”. This is a small but significant number that contributes to less squirt (angle). Vectors Victor…but some know that.
LAMas
Sr. Multi Functional Engineer
Subject Matter Expert (SME)
Legacy Hughes Aerospace Company.
The .0013" defection of the dowel will be much less when the tip impacts the CB at a glancing angle, without miscueing, and only a fraction of the mass of the CB is acting on the side and (now) the tip of the dowel.
The deflection of a solid .50” diameter cue shaft could be 10 times that or .013” and there is more deflection on a LD hollowed out cue end which could be 10X that or ~ .125” or 1/8”. This is a small but significant number that contributes to less squirt (angle). Vectors Victor…but some know that.
LAMas
Sr. Multi Functional Engineer
Subject Matter Expert (SME)
Legacy Hughes Aerospace Company.
OK, this is accurate (didn't know this "buckling" is what you were describing), but it's still not the cause of squirt. The CB rotating and pushing against the cue stick's end mass causes squirt.
pj
chgo
For those interested, complete descriptions, illustrations, and videos clearly explaining what causes squirt and what happens to the shaft during and after the hit can be found here:
what causes squirt (AKA CB deflection)
The shaft doesn't flex very much while the tip is in contact with the CB, and most of the shaft flex/deflection/vibration occurs after contact due to the sideways momentum imparted to the endmass during the collision. Again, the resource page explains and illustrates this and more in great detail.
Enjoy,
Dave
From Dr. Dave's website (linked above):
"...the more the tip compresses and flexes sideways, the longer the tip will tend to stay in contact with the CB. This would certainly result in more squirt (CB deflection) because effective "endmass" is larger with a longer contact time. Also, the more the tip flexes sideways, the more the endmass of the shaft moves sideways, which would also tend to create more squirt.
...
However, the experiments documented in the Cue and Tip Testing for Cue Ball Deflection (Squirt) video seem to imply that tip type, hardness, and height have very little effect on squirt."
pj
chgo
Last edited:
..........
I concur.:embarrassed2:
lol
Great minds...
pj
chgo