Squirt. End Mass and Cue Flexibility.

[ENGLISH!]

English,
This deserves a separate thread...hint, hint.

Be well.

Agreed... but so did/does the multi axis stuff of which this is related. In fact, that deserves to be in a completely different forum & probably not a billiard forum.

I'm just yet again posting on the even numbers though.

You Stay Well.

 

[Corwyn_8]

" The Meucci Black Dot shaft is made with 35 layers of maple to recreate the grain.."

Play video:
http://meuccicues.com/deflection_videos.html

Taking it at face value, one hypothesis seems confirmed. Deflection is dominantly controlled by the shaft. Despite Mr Meucci's comments, butts don't seem to have much, if any, impact given the likely error bars on the experiment.

Would have loved to have seen the black dot shaft rotated 90°.

Thank you kindly.

 

[ENGLISH!]

Most LD shafts are laminated pie shapes and hit the same regardless of rotation of the shaft. This one used layers like plywood and is LD with the grain layer ends up and down for left and right English with the black dot pointed up.

" The Meucci Black Dot shaft is made with 35 layers of maple to recreate the grain.."

The mass of the front end of the shaft in any orientation of the layers is the same and I suspect that if the cue was rotated with the dot rotated 90 degrees, with the layers horizontal to the slate that the squirt would be greater.

I never bought or tried one for I worried about tip wear if I always kept the black dot up. This is only food for thought and I don't sell or profit from Meucci products and the video may be rigged.

Play video:
http://meuccicues.com/deflection_videos.html

I just looked at the test for that Helmstetter cue & that is NOT the one that was on the original Black Dot test comparisons before Meucci came out with his Power Piston Butts.

The old video had a different Helmstetter cue that hit the best for the least deflection of ALL of the other cues & the Black Dot shaft had the least percentage of improvement over any other cue on that butt.

Mr. Meucci was rather shocked & made the comment, 'That must be a very well made butt.' or something like that.

I think that was the 'genesis' of him developing his Power Piston Series cues.

Here is the 'original test' of the Adam Balabushka cue made by Helmstetter in about 2006.

https://youtu.be/RIKCiJKsjCQ?t=953

 

[LAMas]

Taking it at face value, one hypothesis seems confirmed. Deflection is dominantly controlled by the shaft. Despite Mr Meucci's comments, butts don't seem to have much, if any, impact given the likely error bars on the experiment.

Would have loved to have seen the black dot shaft rotated 90°.

Thank you kindly.

That wouldn't have been a good marketing point.:smile:

Be well

 

[dr_dave]

"The Meucci Black Dot shaft is made with 35 layers of maple to recreate the grain."

Play video:
http://meuccicues.com/deflection_videos.html

Taking it at face value, one hypothesis seems confirmed. Deflection is dominantly controlled by the shaft. Despite Mr Meucci's comments, butts don't seem to have much, if any, impact given the likely error bars on the experiment.

You are correct. CB deflection (squirt) depends only on the effective endmass of the shaft. Now, "net CB deflection" (the combined effects of squirt and swerve, AKA squerve) does depend on many other things, including the weight of the butt, for a given stroke. For more information, see the "Rules of CB Deflection (Squirt) Testing" on the robotic squirt testing resource page. Meucci's setup violates many of these rules. That's why I think his "Myth Destroyer" should be called the "Myth Creator" instead.

[Would have loved to have seen the black dot shaft rotated 90°.

I've done this testing on a well-designed machine with careful testing procedures. For more info, see Diagram 3 and surrounding discussion in "Squirt - Part VII: cue test machine results" (BD, February, 2008).

Enjoy,
Dave

 

[Corwyn_8]

I've done this testing on a well-designed machine with careful testing procedures. For more info, see Diagram 3 and surrounding discussion in "Squirt - Part VII: cue test machine results" (BD, February, 2008).

Yes, I have seen that. Which is WHY I wanted to see Mr Meucci perform the same test, and see what he had to say about the results.

Thank you kindly.

 

[Patrick Johnson]

Corwyn_8:
Would have loved to have seen the black dot shaft rotated 90°.

Dr. Dave:
I've done this testing on a well-designed machine with careful testing procedures. For more info, see Diagram 3 and surrounding discussion in "Squirt - Part VII: cue test machine results" (BD, February, 2008).

For those who don't take the time to look, Dave's test results show that cue orientation (even with a flat laminated cue) has negligible effect on squirt.

pj
chgo

 

[Cornerman]

Yes, I have seen that. Which is WHY I wanted to see Mr Meucci perform the same test, and see what he had to say about the results.

Thank you kindly.

The Meucci Mythbuster has inherent design flaws, which I outlined 15 years ago (or whenever he unveiled it).

I'm sure someone can do a search. Or you can PM me.

 

[LAMas]

For those who don't take the time to look, Dave's test results show that cue orientation (even with a flat laminated cue) has negligible effect on squirt.

pj
chgo

From the chart - 0 - 90 degrees looks like a 5% delta or more than the calculated 1.5% previously posted.

The words "Effective Mass" which is all inclusive including minute amounts for tip compression should be used.

I am good with that...for now.:smile:

Be well

 

[JoeyInCali]

Yes, I have seen that. Which is WHY I wanted to see Mr Meucci perform the same test, and see what he had to say about the results.

Thank you kindly.

So he can twist the facts to favor his shafts ?
His mythbuster was very flawed to say the least .
He once touted he had a zero deflection shaft .

 

[Patrick Johnson]

From the chart - 0 - 90 degrees looks like a 5% delta or more than the calculated 1.5% previously posted.

The chart also shows about the same difference between 0 degrees and 180 degrees orientation, which should show no difference - so I'm thinking they're standard deviation differences (if I'm using that term correctly).

pj
chgo

 

[dr_dave]

The Meucci Mythbuster has inherent design flaws, which I outlined 15 years ago (or whenever he unveiled it).

I'm sure someone can do a search. Or you can PM me.

Freddie,

I've never seen your list. Could you please PM or e-mail it to me, or post it here?

My list is under the "Rules of CB Deflection (Squirt) Testing" on the robotic squirt testing resource page. Meucci violated pretty much every one of those rules with his "Myth Creator" setup and testing procedures.

Thanks,
Dave

 

[Cornerman]

I've not been following this thread, because frankly, there's nothing new here.

But, I'll give me not-new input anyway. Something I think I've posted for ... hmmm... about 15 or so years. Not new, folks.

What "causes" squirt? The mass in effect during the tip/ball collision time. Notice that I didn't and will never (after the Jacksonville Experiment) say "endmass" as it is a misrepresentation. At the very least, the term should be "effective endmass." Okay that's one small nit.

Secondly, people keep asking about stiffness and if it significantly contributes to squirt. People have been talking about stiffness in cues to reduce deflection for as long as I've ever been playing. So, that's since the mid 80's.

Answer: YES!!! But to be clear as mud, stiffness is based on materials and shear strengths. It's the shear characteristics of a material that determine the transverse wave propagation, which determines the length of shaft involved of a collision, which determines the mass in effect. Transverse wave propagation and it's importance in determining the mass in effect during the tip/ball collision.

Reduce the mass in that length, and you reduce squirt by reducing the effective mass in the collision. Reduce the transverse wave length during tip contact, you reduce squirt by changing the effective mass in the collision. De-couple or reduce the rigid coupling of the ferrule from the shaft or the tip from the shaft, you delay the transverse wave propagation, which reduces the length of shaft in effect, which reduces the overall mass in effect during the collision.

Can you then change the stiffness to change the transverse wave length: IMNSHO... within the woods and shape (a tapered wooden rod) that we use to shoot pool, I don't think there's a profile that you can reduce the transverse wave propagation significantly. It might be possible to INCREASE the propagation speed with weird profiling (I-beam? Maybe).

Do changes in stiffness by tapering change the squirt. Sure. But in the grand scheme of things, it's insignificant within the normal realm of shaft profiles (cross section and longitudinal). Variation in wood lots should be more significant. Variations in tips should be more significant. Adding a phenolic tip pad should be more significant (Look back 15 years to Ken Bour, RSB, - wondering why his Predator shaft now has more squirt... for sure it's the tip pad).

So for future cue makers who really think stiffness will make a significant change... I think it will... provided you come up with a material that has a significantly slower shear wave (transverse wave) propagation than today's wood materials, while still allowing you to shoot pool. Will it be a composite? More than likely. I'm rooting for something that has Graphene, which seems to be able to do every other magic thing.

 

[Cornerman]

Freddie,

I've never seen your list. Could you please PM or e-mail it to me, or post it here?

My list is under the "Rules of CB Deflection (Squirt) Testing" on the robotic squirt testing resource page. Meucci violated pretty much every one of those rules with his "Myth Creator" setup and testing procedures.

Thanks,
Dave

Hi, Dave,

http://forums.azbilliards.com/showpost.php?p=1096224&postcount=7

That's one of several over the years. Posts from CCB and RSB are getting harder to find.

My apologies for using the term "lateral wave." For years, I called it that because I was focused on the lateral force at contact vs the longitudinal force. It's obviously the transverse wave or shear wave.

The two main problems with the Myth Buster (aside from what you have on your site) are the overly tight grip and the use of the rigid V-block. In combination, the overly tight grip can add contact time because the additional mass from the robot being added to the equation (vs a human hand and the skin, which gives), which in turn increase the length of shaft involved in the collision, which increases mass of the shaft involved.

If the shaft propagation reaches the V-block during tip contact (which I think it can, given the overly tight grip by the mechanism), then V-block mass would also be added to the tip/ball collision (and squirt multiplies). Meucci built his shaft/ferrule to beat the Myth Destroyer, which is why it does the best in his tests.

 

[ENGLISH!]

From the chart - 0 - 90 degrees looks like a 5% delta or more than the calculated 1.5% previously posted.

The words "Effective Mass" which is all inclusive including minute amounts for tip compression should be used.

I am good with that...for now.:smile:

Be well

=======:thumbup2:=========

 

[app4dstn]

Please don't. Those who don't want to see it can go elsewhere on the forum, and some of us are enjoying it, and don't want to be left out.

Thank you kindly.

+1, this is some interesting stuff.

 

[Corwyn_8]

It's the shear characteristics of a material that determine the transverse wave propagation, which determines the length of shaft involved of a collision, which determines the mass in effect. Transverse wave propagation and it's importance in determining the mass in effect during the tip/ball collision.

Ok, clearly out of my depth here. Can you point me to some literature about transverse wave propagation?

I'm rooting for something that has Graphene, which seems to be able to do every other magic thing.

:thumbup: What's with that stuff?

Thank you kindly.

 

[dr_dave]

Hi, Dave,

http://forums.azbilliards.com/showpost.php?p=1096224&postcount=7

That's one of several over the years. Posts from CCB and RSB are getting harder to find.

My apologies for using the term "lateral wave." For years, I called it that because I was focused on the lateral force at contact vs the longitudinal force. It's obviously the transverse wave or shear wave.

The two main problems with the Myth Buster (aside from what you have on your site) are the overly tight grip and the use of the rigid V-block. In combination, the overly tight grip can add contact time because the additional mass from the robot being added to the equation (vs a human hand and the skin, which gives), which in turn increase the length of shaft involved in the collision, which increases mass of the shaft involved.

If the shaft propagation reaches the V-block during tip contact (which I think it can, given the overly tight grip by the mechanism), then V-block mass would also be added to the tip/ball collision (and squirt multiplies). Meucci built his shaft/ferrule to beat the Myth Destroyer, which is why it does the best in his tests.

Thanks Freddie.

I also experienced and solved the tight-grip issue when we designed the machine at CSU. Here's a pertinent quote from the robotic squirt testing resource page:

The problem with a non-human, extremely-firm robot grip is that it can add significant effective weight to the cue. If the grip is totally rigid, the weight of the machine's "hand" and "arm" completely add to the weight of the cue. For example, if you put an 18 oz cue in a rigid machine grip, and the weight of the machine's "grip" is 20 oz, the cue will act like a 38 oz cue! The result of this is that the CB will not leave fast enough to clear the tip with an off-center hit. The tip will either remain in contact with the CB or catch up after initial contact, creating either a push or double hit. The hit will look and sound normal, but the CB will have more squirt (CB deflection) ... sometimes a lot more (as if there where a miscue). Lot's of care must be taken when using a machine to test and characterize cues that will be used by non-machine humans.

Regards,
Dave

 

[Cornerman]

Ok, clearly out of my depth here. Can you point me to some literature about transverse wave propagation?

It's out of my depth, too. I'm just a lowly mechanical engineer who watched the initial Jacksonville VHS Tapes (with hand scrawled notes!) when Bob Jewett and company presented the material and immediately saw that the sideways mechanical/vibrational wave (transverse wave) answered everything (for me) as to what constitutes the "mass in effect of the tip/ball collision."

You can look up vibration theory and shear wave, transverse wave, etc. They all point to the material dependency that determines the actual propagation velocity of this slower wave vs the longitudinal wave (speed of sound).

Freddie

 

[dr_dave]

It's out of my depth, too. I'm just a lowly mechanical engineer who watched the initial Jacksonville VHS Tapes (with hand scrawled notes!) when Bob Jewett and company presented the material and immediately saw that the sideways mechanical/vibrational wave (transverse wave) answered everything (for me) as to what constitutes the "mass in effect of the tip/ball collision."

You can look up vibration theory and shear wave, transverse wave, etc. They all point to the material dependency that determines the actual propagation velocity of this slower wave vs the longitudinal wave (speed of sound).

For those interested, the super-slow-motion videos and illustrations available via the links on the following pages might be helpful to people having trouble visualizing some of this stuff:

cue vibration resource page

what causes squirt

And more information and resources related to the Jacksonville Project can be found here:

Jacksonville Project resources

Enjoy,
Dave