Cue Tip Contact Myth-Busting Truths in Super Slow Motion
ฝัง
- เผยแพร่เมื่อ 10 ก.ค. 2024
- NOTE - See my follow-up videos that clearly show that a softer tip does not get more spin:
- “Can a SOFTER TIP Put MORE SPIN on the Ball? -- MYTHBUSTING Answers” video: • Can a SOFTER TIP Put M...
- "POWER DRAW and Large-Curve Massé with a BREAK CUE Phenolic Tip!!!" video: • POWER DRAW and Large-C...
- "A Fun CHALLENGE DRILL to Test Your DRAW QUALITY … and SOFT VS. HARD TIP Comparison" video: • A Fun CHALLENGE DRILL ...
Dr. Dave busts many common myths concerning what happens when a cue tip hits a cue ball. Everything is supported by super-slow-motion high-speed-camera footage.
Contents:
0:00 - Intro
0:10 - Myth 1 - Tip Contact Time
0:48 - Myth 2 - Control During Contact
2:07 - Myth 3 - Tip Hardness Effects
3:16 - Myth 4 - Shot Speed Effects
4:23 - Myth 5 - Miscues
5:42 - Myth 6 - Sliding Contact
6:29 - Wrap Up
6:45 - ---- clip montage
CORRECTION:
- at 4m21s, I meant to "no noticeable effect" (not "noticeable effect").
Cue/Tip Info:
- Fury HT with unknown "hard" leather tip
- house cue with Elkmaster "soft" tip
- Players break cue with Bakelite "phenolic" tip
NOTE: Many people have suggested that the longer tip contact time associated with a soft tip would allow the soft tip to impart more spin to the CB. "This is simply false." For the reasons why, see the newly-revised cue tip hardness resource page: billiards.colostate.edu/faq/c...
Supporting Resources:
- Top 100 Pool Myths: billiards.colostate.edu/myths/
- cue tip contact time resource page: billiards.colostate.edu/faq/c...
- stroke acceleration resource page: billiards.colostate.edu/faq/s...
- cue tip hardness effects resource page: billiards.colostate.edu/faq/c...
- miscue resource page: billiards.colostate.edu/faq/f...
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Good Luck With Your Game!!! - กีฬา
![คุณอาเรียโต๊ะข้างๆ พูดรัสเซียหวานใส่ซะหัวใจจะวาย ตอนที่ 2 [ซับไทย] 【Ani-One Thailand】](http://i.ytimg.com/vi/kbbfYakMY8k/mqdefault.jpg)
*NOTE* - See my follow-up videos that clearly show that a softer tip does not get more spin:
- “Can a SOFTER TIP Put MORE SPIN on the Ball? -- MYTHBUSTING Answers” video: th-cam.com/video/JXeOl9m5TFk/w-d-xo.html
- "POWER DRAW and Large-Curve Massé with a BREAK CUE Phenolic Tip!!!" video: th-cam.com/video/NZcZlJNW5IA/w-d-xo.html
- "A Fun CHALLENGE DRILL to Test Your DRAW QUALITY … and SOFT VS. HARD TIP Comparison" video: th-cam.com/video/T8vTQ3TGJlo/w-d-xo.html
*Contents:*
0:00 - Intro
0:10 - Myth 1 - Tip Contact Time
0:48 - Myth 2 - Control During Contact
2:07 - Myth 3 - Tip Hardness Effects
3:16 - Myth 4 - Shot Speed Effects
4:23 - Myth 5 - Miscues
5:42 - Myth 6 - Sliding Contact
6:29 - Wrap Up
6:45 - ---- clip montage
*CORRECTION:*
- at 4m21s, I meant to "no noticeable effect" (not "noticeable effect").
*NOTE:*
Many people have suggested that the longer tip contact time associated with a soft tip would allow the soft tip to impart more spin to the CB. "This is simply false." For the reasons why, see the newly-revised cue tip hardness resource page: billiards.colostate.edu/faq/cue-tip/hardness/
*Cue/Tip Info:*
- Fury HT with unknown "hard" leather tip
- house cue with Elkmaster "soft" tip
- Players break cue with Bakelite "phenolic" tip
*Supporting Resources:*
- Top 100 Pool Myths: billiards.colostate.edu/myths/
- cue tip contact time resource page: billiards.colostate.edu/faq/cue-tip/contact-time/
- stroke acceleration resource page: billiards.colostate.edu/faq/stroke/acceleration/
- cue tip hardness effects resource page: billiards.colostate.edu/faq/cue-tip/hardness/
- miscue resource page: billiards.colostate.edu/faq/foul/miscue/
*Subscribe to Dr. Dave's TH-cam Channel:*
th-cam.com/users/DrDaveBilliards
I'd be curious what you think of Cesar Muroya's latest video "Controversial Push Stroke..." in the situation where the cueball is very close to the object ball and you're hitting at slightly over ninety degrees to angle of direction -- oh, better look at video, I can't describe it well...
Link related to my above comment:
th-cam.com/video/eCVL3I9y63E/w-d-xo.html
@@sdrtcacgnrjrc That was definitely a bad call. The CB heads in the tangent-line direction, so there was no "push" or double hit. Anybody who doubts this should review the videos and info here:
billiards.colostate.edu/faq/foul/double-hit/
billiards.colostate.edu/faq/foul/push/
Then why not just use a phenolic tip and never have to change it or shape it?
Impressive! But English snooker players will always disagree...
Dr. Dave, I have a tremendous amount of respect for you, but I think at least one of your conclusions is wrong. If a soft tip stays in contact with the cue ball up to 50% longer that HAS TO MAKE A DIFFERENCE! While I don't experiment with different tips much, I have gone to a softer tip because that was what I had available to me.
I immediately noticed more "action" on my draw, follow, and left and right english. It was quite noticeable in fact, and actually caused me some issues with making shots and getting position as the cue ball had more action. Also, a friend of mine, who had used my cue with a harder tip, mentioned that he was getting more spin with my cue. I had not told him I had changed tips.
I firmly believe, and your own evidence suggest this, that a softer tip imparts more spin. It would be different if the difference was only say 3-5%, but you are mentioning up to a 50% difference. It is hard to believe that additional contact time does not make a difference on spin.
Explanations for why a softer tip cannot apply more spin can be found here:
billiards.colostate.edu/faq/cue-tip/hardness/
Is that the same as more contact time not being able To impart more spin?
@@filthymcnastyazz Yes. More contact time does not allow you to impart more spin per the detailed explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
Yes, he did a wrong calculations. He used stiff interactions, where there is a spring force. Rookie mistake.
@@jan.kowalski A soft tip does deform more and stay in contact longer with a lower peak force (but still a very small interval of time), but this is unimportant to the action of the shot based on the detailed explanations here (and at the links on the page):
billiards.colostate.edu/faq/cue-tip/hardness/
It is the total "impulse" (integral of force over time) and momentum change that is important (which is the same for both the hard and soft tips).
Dr Dave, as an engineer, I think you need to add units to your table. You’re stating 1.9 thousandths of a second, but the table should also have this unit.
The units are "ms." I don't like to "clutter up" videos with too much detail, but your point is well taken.
If the cue ball literally only is in contact for that microsecond, then wouldn’t say, the whole practice of “staying down on the ball through the shot” be completely irrelevant to accuracy. Or that a straight follow through is essential for accuracy. Literally, both of those things have 0 impact on where the ball goes
Follow-through is important for the reasons here:
billiards.colostate.edu/faq/stroke/follow-through/
The importance of staying down is described in the videos here:
billiards.colostate.edu/faq/stroke/technique/
But how is the cueball reacting to the 0.4-0.9ms differences? And how are the time differences insignificant? I could see if the difference was less than 5%, but you’re talking 16%-50%.
LOL. Yes, just because the time is still really small doesn't mean a 50% difference doesn't matter! Even a 25% difference.
The reasons are explained in detail here:
billiards.colostate.edu/faq/cue-tip/hardness/
I agree with you bro, any amount of contact time effects the cueball tremendously.that’s why people have different strokes. I think dr is wrong on this subject.
@@peymanghorbani6390 Even if different strokes created different contact times (I have not seen evidence for this), the differences would be unimportant for the same reason why the differences in contact times with tip hardness and shot speed are also unimportant. The reasons are explained in detail here:
billiards.colostate.edu/faq/cue-tip/hardness/
billiards.colostate.edu/faq/cue-tip/contact-time/
@@DrDaveBilliards , so why does a long stroke with good even acceleration cause more draw as opposed to a short jabbing stroke, with a sudden pull back on the cue?
@DrDaveBilliards, let just saw a post down a little that might answer my question! Thank you for all you do for the pool community!
Need to do a myth bust of the different cue tip sizes. Penny, Nickle, Dime
See:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
Thank you very much. I had several hours of arguments in my life and words simply couldn't convince people. I can just send them the link to this video now and call it a day, use the time to actually play pool. Thank you Dr. Dave!
And if that is not enough, also send them to this page: billiards.colostate.edu/faq/cue-tip/hardness/
Intersting and informative. Great video Dr. Dave!! Thanks!!
You’re welcome. I’m glad you liked it.
have been playing this afternoon. good to see these images.
Your data proves that Myth #3 is correct. The soft time has a contact time that is 50% longer than the hard tip. 50% is a large increase. You are focused on actual time elapsed, but when making comparisons, it is important to look at the percentage differences.
A soft tip stays in contact longer, but this is unimportant to the action of the shot per the explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
@@DrDaveBilliards I think most pro players would disagree with your assessment. I know several pro players have YT videos discussing their choice of tips. If they could not differentiate a difference in the outcome of the shots, if the choice of tip did not effect their consistency, they certainly would not be particular in their choice of tip. Darren Appleton specifically prefers the Sniper tip even though they are not a sponsor of him.
I disagree with "most." Many pro players prefer hard tips for all the reasons here:
billiards.colostate.edu/faq/cue-tip/hardness/
Some prefer soft tips because soft tips sometimes hold chalk better, because they give a softer and less noisy hit, and because it might be easier to control finesse shots (since the hit is less efficient, giving less CB speed for a given stroke).
Superb work -- as always. Thanks.
Thank you, and you're welcome. I aim to swerve. :)
This is a great video. It put me to sleep better and quicker than TH-cam sleep music.
Sleep well. Play better.
Very interesting. Thanks Dr. Dave.
You’re welcome. I’m glad you liked it.
Dr Dave, it's too bad you were not available to me when I was 10 years old and first picked up a cue.
I could have been a world beater! I am 69 years young now!
It is never too late to improve. I'm 58 and I am still improving my knowledge and my game.
This videos is kinda proof that sometimes more graphs and information is not the answer
You and others might instead prefer the info, illustrations, other videos, and explanations here:
billiards.colostate.edu/faq/cue-tip/contact-time/
billiards.colostate.edu/faq/cue-tip/hardness/
billiards.colostate.edu/faq/sidespin/maximum/
@@DrDaveBilliards bit too convoluded for me sorry. I feel your disregard of the human element of pool to be wrong. The human mind and body is the most complex thing on the planet, and our senses enable us to do/feel things that are almost imperceptible or explainable
I definitely appreciate how useful "feel" can be in pool. Almost everything in pool requires solid intuition and "feel." I also understand and have documented the importance of the mental game:
billiards.colostate.edu/faq/mental/
Amazing video as always DrDave!
Thanks!
Another great informative video, I've gained great pool knowledge from watching your videos and always encourage my pool buddies to watch them too.
Thanks. I'm glad to hear it.
Fantastic information, had no idea the contact time was so short. My inquisitive mind started wondering how long a baseball bat and ball stay in contact. Researched and found it's in the same range.
This was very informative. Great job! Awesome video!😊
I'm glad you liked it. Thanks!
please dont get fooled by this total BS, nothing to do with actual billiards
I’m sorry but more than a 40 percent increase in duration of contact is a significant difference. Sure the amount of time is really small but it’s completely relative
For explanations for why longer contact times are not important (at that level), see:
billiards.colostate.edu/faq/cue-tip/hardness/
@@DrDaveBilliards thanks 🙏. Ya when I made the other comment I was busy and intended to read the link you shared.
@@DrDaveBilliards huh interesting.
Well done Dr Dave as ever!
Thanks Nic!
Thanks! I enjoyed!
You're welcome! I'm glad to hear it.
I imagine that a ball that is in contact with a tip for half the time, hard vs soft tip, would have a large difference in the amount of spin imparted onto the ball. I would like to see some numbers on what the difference in RPMs is between soft and hard tips.
It definitely does. even though we're talking thousands of a second. try putting a soft piece of rubber as a tip on a cue and see the incredible amount of side you can get on a cue ball. and as a result transfered side to an object ball as well
Absolutely no question about it. Softer tips do impart more spin. I never believed it before and honestly didn't care about what tip I used as long as it was not phenolic. Then I changed to a softer tip because that is what I had on hand and there is no doubt the EXACT SAME CUE gives me more follow, draw, and english. No doubt at all.
Detailed explanations can be found here:
billiards.colostate.edu/faq/cue-tip/hardness/
totally agreed - what needs to be "quantified" is the relationship between the contact time (already determined) and the rpm of the cue-ball after contact which presumably could be determined by analyzing the same video.
@@DrDaveBilliards until you get a mechanical arm to hit the ball the same speed no one is going to buy it, even if you're right that there is no difference. Hitting the ball yourself is not a good measure because you are going off feel to create the same force and that is too subjective. Not to mention the bias of the person putting on the experiment influences any experiment, and in this case is also the test subject, amplifying the bias.
Interesting video.
My only question is “who is striking the ball”?
Pros and amateurs contact the ball very differently. What many players say the difference is hitting the ball, or pushing it.
When I’m “pushing the ball”, the contact feels 1000x different that when I’m hitting it. And the feeling in my hand tells me the contact is more than illustrated in this video.
What your hand feels is mostly after the CB is gone. The cue's momentum does all the work during contact. For more info, see:
billiards.colostate.edu/faq/grip/light-vs-tight/
billiards.colostate.edu/faq/cue/feel/
billiards.colostate.edu/faq/stroke/acceleration/
billiards.colostate.edu/faq/stroke/good-timing/
billiards.colostate.edu/faq/cue/weight/
BTW, the shooter in the video has a very typical good stroke with smooth acceleration into the ball, like most good players.
On the CB slide portion of the video you talk about how the tip "grabs the CB and how it deforms". Wouldn't that be the result of using a soft tip? If the tip takes on the shape on the cue ball when struck and expands back out, it will definitely give the tip more contact time on the cue ball. Is it me, or is the 1st myth and last myth kind of contradicting?
The tip grabs the ball equally well with a hard or soft tip. A soft tip stays in contact longer, but this is unimportant to the action of the shot per the explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
I'll need to watch some more of these. Precision is a key to good play and you can definitely feel the difference in how you hit the ball. As a player of many years, the hardness of the tip does make a difference. But I can play with almost any fairly straight cue with a good tip, you just have to make adjustments to compensate as best you can. The tip is just the tip of what's involved. ;)
Any good player can adjust to any tip, regardless of the "feel," assuming the tip holds chalk. For more info, see:
billiards.colostate.edu/faq/cue-tip/hardness/
billiards.colostate.edu/faq/cue/feel/
BTW, the brand of chalk really doesn't matter much either (unless it is one of the "cosmetic" style chalks that sticks to the CB too much):
billiards.colostate.edu/faq/chalk/comparison/
Very similar idea in tennis. People think they have control over what they do with the ball at contact. Truth is, the ball is already gone. Nice video!
Awesome work, beautiful footage, I will explain with bases to my friends why a miscue is a foul o double contact
FYI, I have a lot more videos and info dealing with miscue fouls here:
billiards.colostate.edu/faq/foul/miscue/
Especially check out the first video there.
My observation watching the contact times, The cue ball moves approximately 2MM during contact time with the soft tip and 1MM with the hard tip. Less then 1mm with the phenolic tip. I used small sticky notes to mark the cue ball movement, beginning and end of the cue tip contact. There is a noticeable difference.
There is a difference, but the difference has no important effect per the info and explanations here:
billiards.colostate.edu/faq/cue-tip/contact-time/
and here:
billiards.colostate.edu/faq/cue-tip/hardness/
Enjoy!
@@DrDaveBilliards Thanks Dr. Dave, Always thought the contact time was much longer.
@larryvietvet543 Many people do, hence the "Myth Buster" label.
Great vid, very interesting
Thanks. Also check out the follow-up videos and detailed explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
Fantastic!!!!
Thanks!!!!
Thanks Dave this very interesting
You're welcome. I'm glad you think so.
The psychological effects of hard vs soft would be a good candidate for a study. I suspect some people probably slow down their shots subconsciously with softer tips to impart more spin. Physics don't lie.
You are correct. Physics and careful experiments don't lie.
Beautiful video but with wrong conclusion. 1,9ms shouldn’t be considered long or short time. It is what it is. That’s the time of the contact that we have in this game. And it is wrong to compare that time with the time that a football players leg touches the ball, or the golf stick touches the golf ball, calling it long or short.
What matters - is the fact that there is 25%difference between 1,9 and 1,5 on your picture. And that explains a lot.
The fact, that you can do screw backs in this game itself means that your tip moves the ball. Otherwise the cueball would always jump, because the vector of force is directed from the point of contact through the center of the cue ball, that is to the ceiling. And longer the contact you have, more accurate the shot and stronger the screw back you will get.
I don’t to write a lot, no one will read anyway.
But i don’t think that someone will be able to repeat what is done here with a break cue.
But if in next 100 years someone reproduces it, then i would suggest him to take a steel cue with a steel tip and try again. With a steel tip you will have almost 100% of difference in a time of contact in comparison even with a break cue. Instead of 0,8 Ms you will have 0,00008 Ms. Feel the difference!
th-cam.com/video/NSDpVUFJ-74/w-d-xo.html
For explanations for why longer contact time does not result in more spin, see:
billiards.colostate.edu/faq/cue-tip/hardness/
BTW, contact times with draw shots are not much longer than with center-ball-hit shots, still in the 1-2ms range. More examples can be found here:
billiards.colostate.edu/high-speed-video/
I like your explanation, but you will never sway Dr. Dave. I respect Dr. Dave and he serves the pool world admirably -- far beyond any other "teacher." Once in a while a tutorial will come along, seemingly controversial to many. I humbly tried it once but got a "smack" from the usual regurgitated trope. The feel of the player in his stroke and his consciousness are wrapped up as one intrinsically in his execution, and he can feel the the subtle vibrations in his arm -- just how he did.
I enjoyed your mythbusting video.
I'm glad to hear it. If you are interested, check out my follow-up videos, info, and links here:
billiards.colostate.edu/faq/cue-tip/hardness/
I think a person will sleep better at night knowing that with a softer tip , you’ll have fewer miscues ? When hitting in the outer zone , especially if your hitting at steeper angle .
As long as a hard tip holds chalk, and one chalks properly, miscues are no worse.
Mind Blown!
Is Myth 1 only busted for a center ball hit, since the footage used in that section was only center ball hits? My intuition is telling me for draw/follow/side shots, this would maybe show different results. Since you wouldn't be hitting center of mass, it 'seems' the cueball would not leave the tip as quickly as a center ball hit at the same speed, as the energy would be divided between the forward motion and the rotation. But it's just an intuition, since I know zero about physics.
True. Off-center hits will have slightly different contact times.
How can you say that half contact time has no effect because the numbers are so small? It’s all about scale, the numbers still have measured separations. There’s a clear difference between hardness. Logic like that brings into question the whole video.
A soft tip has different hit efficiency, feel/sound, contact-patch size, and contact time, but for a given tip offset and CB speed, there is no difference in the action of the shot (e.g., CB spin) for a hard vs. soft tip per the explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
I play with soft tips and I carry sandpaper in my wallet so I always scuff the tip to suede, allowing it to hold more chalk. Sometimes on an English shot I will give the pool cue a small twist. I am pretty sure I can hold the ball longer than 1.9 in this fashion. I can feel the side of the cue roll across the surface of the ball
Most of what you feel is after the CB is long gone. It is impossible to feel what happens over a few milliseconds. For more info and explanations, see the info and links here:
billiards.colostate.edu/faq/cue-tip/hardness/
Concerning swiping or swooping your stroke to get more spin, see the videos and info here:
billiards.colostate.edu/faq/stroke/swoop-swipe/
Nice billiard educational video. Love u dr dave 👏👍👍
Thanks!
great stuff, can settle lots of conflicts.
... or create more for the people who refuse to accept the logic, reasoning, and visual evidence.
Thousands of Newtons of force can make a considerable difference even in hundreds of microseconds. This is especially true for spin. The cue ball momentum is independent of the tip, but the friction and spin is much better with a soft tip.
More force over more time does make a difference, but the rest is not true based on the explanations and supporting videos and links here:
billiards.colostate.edu/faq/cue-tip/hardness/
Check it out.
@@DrDaveBilliards My experience says the opposite. Five years of trying never made a hard tip perform as well as a soft tip. The difference is not huge, but trying for extreme spin with a hard tip always results in a miscue.
@@byronwatkins2565 he just did a wrong calculations thinking in terms of stiff interactions. Obviously, which video shows, there is an additional spring force.
Pretty Cool stuff.😮
I need to see you tell people that titanium ferrules are also a gimmick. Impossible physically to affect the shot
Actually, if it is lighter than the ferrule it is replacing, that would decrease CB deflection:
billiards.colostate.edu/faq/squirt/endmass
and lower CB deflection has potential advantages:
billiards.colostate.edu/faq/cue/low-squirt/
Thanks!
I'd like to learn more about the velocity or acceleration on draw shots and when you miscue. Would be interesting to get down to the ms level to understand what's going on.
We don't really need a high-speed camera to know what is and isn't a good draw stroke. All you need to know is here:
billiards.colostate.edu/faq/draw/advice-and-drills/
Great video but wrong conclusions imho, tip hardness makes up to 50-100% change, can't be neglected. If it didn't matter why not just play with phenolic all the time)
Yes, the conclusions made here don't make sense in some cases.
Explanations supporting my statements can be found here:
billiards.colostate.edu/faq/cue-tip/hardness/
Not only that - he calculates all as a physics of stiff body yet, even in video, there is a visible additional spring force.
@@jan.kowalski A soft tip does deform more and stay in contact longer with a lower peak force (but still a very small interval of time), but this is unimportant to the action of the shot based on the detailed explanations here (and at the links on the page):
billiards.colostate.edu/faq/cue-tip/hardness/
Venom begs to differ he says his bending the cue into the table is what gives his extra draw power plus his body english. You should super slow motion him.
It is not the bending of the shaft after the hit that gives the power, it is the long, complete, and relaxed acceleration into the CB with a low tip position that creates good draw action and causes the tip to finish into the table with complete follow through (causing the shaft to bend). See:
billiards.colostate.edu/faq/stroke/acceleration/
billiards.colostate.edu/faq/stroke/follow-through/
billiards.colostate.edu/faq/draw/advice-and-drills/
Enjoy!
Question for Dr. Dave. 2 scenarios, if the grip is stronger versus weak/ no grip power at all, with the same cue speed hitting the cue ball, would the stronger grip gives longer impact time which results in more reaction and power transferred into the cue ball from the cue? Assumping all the other factors staying the same - i.e. speed, cue weight, and all that
See:
billiards.colostate.edu/faq/grip/light-vs-tight/
Thanks for the great video! 😊 And very surprising. I always believed and felt that long follow through accelerates the spin on the ball. 🤔
The follow-through is a sign of a good stroke, not the reason for it. See:
billiards.colostate.edu/faq/stroke/follow-through/
Follow thru, IMHO, is about preventing noobs from decelerating the cue before stroking the cue ball, but instead making a smooth stroke throughout.
@@tolkienfan1972 Agreed. See:
billiards.colostate.edu/faq/stroke/acceleration/
I think a collab with @smartereveryday is now a must
I have tried to reach out to Dustin before. Maybe it is time to try again.
Great video
Thanks.
love the slo mo views
Alan Hopkins has been a champion pool player despite a stabbing stroke. This research br Dr Dave et al shows why his stabbing stroke produced results as good as other champion pool players with smooth strokes - the CB to OB duration is so brief that the good results come only from a chalked tip hitting the desired spot on the OB while the cue is aiming in the proper direction. I have instructional videos by Freddie "The Beard" Bentivigna on Banking. He taught that certain shots required a firm, or sometimes a loose, grip on the cue. Dave disproves that. But Freddy also taught what he called using a "dead level cue" which probably is a good stroke to master - though 'level' is not possible for most shots, because the rail clearance requires at least a bit of downward angle on the cue.
Good point. A stabbing stroke is not the best approach for most people, but it can be mastered by some.
It's interesting on the draw show miscue that most people say the miscue is caused from hitting under the cue ball to begin with. When in this you can clearly see that the hit is in the correct place to begin but then drops below to scoop.
Would love to see more of in this slowmo format. It's beyond interesting.
FYI, I have lots of slow-motion videos here:
billiards.colostate.edu/high-speed-video/
Enjoy!
NO Jeffery the video shows A WAY you mis-cue. Most people mis-cue from hitting under the ball. This video gives you just 'bout enough info to make people think they know whats goin on
@@lgold3416 Most people who scoop the ball on draw shots do so because they are tensing up the arm and stroke which causes the tip to hit much lower than they intend to. See:
billiards.colostate.edu/faq/draw/advice-and-drills/
and:
billiards.colostate.edu/faq/foul/scoop/
The lower the contact the more likely the slipping.
@@rebeuhsin6410 No doubt about that.
In your "Tip Contact Time" portion of the video you are doing the testing using a tip that is very low. I believe the results would be different if you use a new soft or SS tip. The tip compression time has to change things in this regard, right?
You are correct. A taller soft tip plays even softer.
This is great, thank you. Have you studied the affect of surface area contact. Maybe, the affects people describe with a softer tip aren't contact time, but surface contact area? Or, maybe the two work together enough thatf a pro can tell the diffrence between a soft and hard tip when it comes to spin or other claimed affects.
There are some performance-related differences between soft and hard tips. For more info, see:
billiards.colostate.edu/faq/cue-tip/hardness/
Can you make a video next on the anatomy’s of the stroke , like what different muscles groups do when you stroke . Your the only one that can do it Dave 🙏🏼
Use the muscle between your ears.
I’m not that kind of doctor. 🤓
IMO, what is more important (to a pool player) is all the technique concerns related to the stroke, which I already cover in great detail in numerous videos under all the subtopics here:
billiards.colostate.edu/faq/stroke/
The only thing missing is the equipment used to swing the the stick in the slow motion videos. Surely that was not done by a human being. It would immediately null out all the numbers in the Tip/Speed chart. Especially the Slow vs Fast cue speeds.
Doesn't matter anyway. We're talking 1000s of a second difference. Nobody can judge that with the naked eye
If you do enough trials and only keep the good ones (where the CB travels the target distance), and if the results are consistent, there is nothing wrong with the reliability of the data. That’s what we did.
Thanks, and i curious to know, if its 1ms impact, why is follow thru stroke so important? As this would conclude that basicly you just need to deliver power to some point on CB and basicly stop cue right there?
The only thing that matters is tip contact point and speed. That’s it. Literally no other things matter. How you get there doesn’t matter.
The follow-through is the result of good fundamentals that allow the player to consistently return the tip to the desired spot on the cue ball with the desired speed. Without the proper follow-through, there is a tendency to tense up, start slowing down, and move offline prior to contact.
Follow-through is a movement used in almost all physical sports to assist in consistency and creating a repeatable process.
Follow-thru is important and does matter. In fact during this video the graph depicting cue speed tells the tale. The cue should be accelerating to its maximum speed just prior to contact, contact the cue and lose speed, then recover its forward momentum until the stroke length depletes the stroke speed. If you don’t follow through, then you are “hitting” the cue ball no not stroking. This will pocket a ball, but like in baseball, swinging through the impact delivers a more precise and thorough strike on a ball. Same in golf. You don’t see pros stopping at impact once the golf is struck.
Pool is about. “Stroke” not a “hit”. Without the follow through, you get a “hit” and a deceleration of the cue at impact.
I think it's part of good form for delivery to a straight stroke giving more consistent hit speeds and able to consistently hitting your target. Some people just poke or jab at the cue ball and are probably less consistent. Look at how a beginner strokes vs a pro. No way the amateur can be consistent. Some pros do have awkward strokes and styles, but can do that consistently. Willie Mosconi and Keith McGready had sidearm strokes, but were obviously very good. Allen Hopkins was winning at high levels for awhile, but has a terrible stroke. I imagine if you use your terrible stroke, but have practiced and played for many years with it, you could still become very good.
Awesome stuff as usual, Dr. Dave.
I'd argue that a soft tip still stays in contact about 50% longer than a hard one, even though the absolute value is in millisecond rage. Not sure we can dismiss that. A soft tip appears to impart more spin than a hard one - at least that's how it feels to me. Or it that too a misconception? :)
Likely more deflection too. Longer contact time more time to push cueball off course. I pocket firm cuts with outside better with a harder tip. Problem is the slow shot have a more chance for miscue with a hard tip. Try running a rack with your break cue. Results are surprisingly good.
Yes. I think it is hard to ignore that a soft tip stays in contact longer. A few months ago I went to a softer tip with the exact same cue. There is no doubt that the soft tip puts more spin on the ball for me. In fact, a friend of mine used my cue BEFORE I changed the tip, and then a few months later he was using my cue again and said "wow, I am getting a lot more action today." I had not told him the tip had been changed. I then told him, and he was surprised it made a noticeable difference.
A soft tip does not impart more spin. For more info, see the explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
@jamesdavis8731 - Perception isn't always reality. For instance, I can get the exact same amount of draw distance with both my Kamui super-soft tip on my playing cue and my phenolic tip on my break cue. Tip hardness doesn't actually affect the amount of spin that can be generated. There are a few factors that might be contributing to the more action you're seeing... the softer tip might have a better dime shape than your harder tip did. Your softer tip might also be retaining a good layer of chalk more than your hard tip was. It's also possible your softer tip has a slightly smaller diameter. These would certainly allow for cleaner hits towards the outer areas of the cue ball, thus producing more spin.
Interesting. So leaving the "feelings" aside, there should be no reason to use a soft tip:).
From my experience, soft tips appear to generate more spins on soft shots, but less spin on hard shots compared to hard tips. (as explained in Dave's link).
Clearing away BS is... good.
Busted BS!
It would be interesting, and possibly settle some of the questions raised in these comments, to see cue stick speed graphs for different strokes - strokes with too tight a grip, stokes with long follow through, and strokes with short follow through.
I think I already cover all these things fairly well here:
billiards.colostate.edu/faq/stroke/acceleration/
and here:
billiards.colostate.edu/faq/stroke/follow-through/
and here:
billiards.colostate.edu/faq/grip/light-vs-tight/
Check it out.
When you play a jump shot, does the cueball get out of the way in time to avoid a secondary hit with the tip?
Yes. If you search or scan for "jump shot" on this page, you can find slo-mo videos showing that this is the case:
billiards.colostate.edu/high-speed-video/
Thanks for the footage, it does show that softer tip have more contact area into cb during hit although the contact time difference is negligible, the contact area is not, does that area adds more grip to cb? Even if it does, it most likely not much, but in this game, one hair can make a shot or miss a whole game
See the “contact patch” paragraph near the bottom of the page here:
billiards.colostate.edu/faq/cue-tip/hardness/
Thank you for the excellent analysis. Do you have similar one for cue ball impacting object ball in slow motion, showing if there is any elastic or inelastic deformations, and how spin on the cue ball is transferred to the motion of the object ball?
Ball collisions occur much faster. I have a video and info here:
billiards.colostate.edu/faq/ball/contact-time/
I have lots of stuff concerning spin transfer to the OB here:
billiards.colostate.edu/faq/throw/spin-transfer/
Enjoy!
@@DrDaveBilliards Thank you, those very very good.
Curious if any videos exist on new CF deflection test with cheap light balls and new slippery cloth. Played an event recently and found light CB was deflecting off aiming line causing some missed shots. I would love to see cheap vs expensive balls and new vs old cloth testing
I've done some CF shaft testing in the videos here:
billiards.colostate.edu/faq/cue/carbon/
Slippery cloth and polished balls definitely increase CB deflection by delaying swerve. One always need to be able to adjust to conditions. There are many effects you need to be aware of when aiming with sidespin, per the info here:
billiards.colostate.edu/faq/sidespin/aim/
But this raises a question why we need follow throw if the contact is that small..
See:
billiards.colostate.edu/faq/stroke/follow-through/
Thanks for sharing this. very interesting. One additional factor that would be interesting to understand would be how contact area of the cue tip to the ball affects the cue ball response and how cue tip hardness in turn affects surface area contact. It would seem intuitive that softer tip creates a greater surface area contact but slow mo evidence and measurement would be fascinating. Does contact area make a real difference?
A softer tip definitely has a larger "contact patch" size, but it is mostly unimportant. For more info, see:
billiards.colostate.edu/faq/cue-tip/hardness/
Wow. As someone who is not an avid billiard player (though I enjoy it when I get a chance), it is interesting to see people's reaction to this. It seems there are so many factors to consider on the question of cue tip softness. At the moment, I am not convinced either way, but I am assuming Dr. Dave did actually test the spin of the balls hit with the different tips, right? If so, then I think I would side with him on this issue. However, I do love soft tipped cues. My guess is that, beyond the psychological issue, there are many factors in the real world that can make a difference that it would be hard to make a determination based on the tip alone. Are you miscueing? Are you really hitting the CB in the same location? Are you hitting with the same speed? Or are you just more confident? However, since the softer tips do have more contact area, would this be more forgiving, in terms of the player's aim?
If you want to be better convinced, see the follow-up videos and detailed explanations (with supporting links) here:
billiards.colostate.edu/faq/cue-tip/hardness/
What are the effects when cloth has a lot of chalk dust buildup on it? Is there more or less speed? Is there more or less effect with english?
Dirty cloth plays slower and spin takes more on the cushions.
Please explain why you need so much follow through for draw? The contact time doesn't seem to matter...
If you don't have follow through, it means something was wrong with your stroke (usually tension, which can limit draw potential). For more info, see:
billiards.colostate.edu/faq/stroke/follow-through/
and:
billiards.colostate.edu/faq/draw/advice-and-drills/
Hay Dave, thx for the Videos. I Have ove myth/question. Look at the graph at 1:33. According to the graph the ball is hit with constant speed = Zero acceleration. Dv/ dt = 0. The mystery is about if one can increase the time of tip contact if dv/dt is non Zero. So, if one strikes the ball with the speed that is found in the graph at 1:33 for x value (cue distance = 4) equal to approx 4.2. At that x Value dv/dt is clearly not Zero, hence the acceleration is non Zero and therefore one should get longer contact time; question mark. 🤔
Even if accelerating into the CB created different contact times, the differences would be unimportant per the info here:
billiards.colostate.edu/faq/cue-tip/hardness/
billiards.colostate.edu/faq/stroke/good-timing/
But most good players reach max speed at the CB; otherwise, the acceleration has bad timing (is too late) and is not useful.
Thanks. It would be interesting to see the graph of cue speed for a light and heavier stick.
Agreed. I would think the shapes would be similar; although the lighter cue would obviously require more speed to get the same CB speed.
@@DrDaveBilliards Maybe not since the CB leaves so quickly. I would expect less acceleration loss after contact with a heavier cue though.
@@jeffren70 If you are really curious about this, see my "TP A.30 - The effects of cue tip offset, cue weight, and cue speed on cue ball speed and spin" analysis here:
billiards.colostate.edu/technical_proofs/new/TP_A-30.pdf
You don't need to know all the math and physics to scan through for the conclusions.
Hi, what does tip size determine. How does it affect performance. Such as 13mm, 12.50mm, 12.25mm, etc. Is it true that the larger the tip, the more lee way for accuracy, the small the tip the more accurate you have to be but can produce more spin? And lastly what size do you prefer?
Thanks
See:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
I don't have a strong preference. I used a 11.75mm Z-2 for many years. Now I have a 12.4mm Revo.
Very good!
Thanks!
I know nothing about this and very little about physics, but wouldn't a softer tip be able to impart slightly more spin due to more surface area contact?
Short answer: No.
Long answer: billiards.colostate.edu/faq/cue-tip/hardness/
It would be valuable to know does the shape of a cue tip effect the duration of cue ball contact? There are many “opinions” that a flatter tip profile imparts less spin and maintains contact longer. True or not?
I don’t think tip shape or hardness limit the amount of spin that can be applied. For more info, see:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
and:
billiards.colostate.edu/faq/cue-tip/hardness/
I looked through your videos... may have missed it. Have you done a video on nickle vs dime radius? Would be nice to see a closeup slow motion of how much difference there is in cue ball contact...especially with only a millisecond of actual contact. Which is better?
Second that request.
Also interested in seeing a flatish tip as well.
I have lots of info on tip size and shape effects here:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
A friend told me nickel for trust dime for confidence.
@@BROU-bb2uc It really doesn't matter much per the info and illustrations here:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
Corollary to the first two busted myths, I hope you can do a video on why follow through seems to matter. That would settle a decades-long argument I've had with some pool friends.
I cover this topic here:
billiards.colostate.edu/faq/stroke/follow-through/
@@DrDaveBilliards thanks for the link!
@@raymondgirardtan4978 You're welcome. I aim to swerve. :)
😆
Can you explain then why there is punch stroke where you can instantly draw the cue ball back and with follow through the cue ball can go a bit to the side and then draw back?
Sorry, but I don't understand your question and how it relates to my video.
One way to draw the CB back quickly is described and demonstrated here:
billiards.colostate.edu/faq/draw/quick/
And both draw and follow are possible with a very short stroke using some of the techniques here:
billiards.colostate.edu/faq/foul/double-hit/
Which is recommended, the dime, or the nickel shaper?
The tip I’m using is a Kamui Clear Medium (which has wore down to almost ferrule point).
It doesn't really matter much, per the info here:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
Superb
Thanks!
@@DrDaveBilliards
U. Got it
Now that I am 71 years old with macular degeneration.
It's amazing to see all these shooters and how good they are.
I used to be fair in my day, mainly on bar room tables.
But now life is changed.
We sure do get old fast.
Keith Kuhn
KK Motion Pictures
On TH-cam also
I'm sorry to hear about the macular degeneration. Bummer.
@@DrDaveBilliards
Thanks Dave.
Pool is a. Beautiful
Game
Agreed. Downright gorgeous.
I used to play with soft tip believing it get more spin. After changing to hard tip, I now know that it is not true at all. The only difference I found was how the shots would feel i.e. soft tip feels dampen/springy upon contact and hard tip feels like a truck hitting a car. Other than that, there are slight differences to CB throw off on swerve shots.
Would be nice if there is a new type of cue tip that allows us to get rid of chalk though.
A chalk-less tip would be awesome, and very profitable (except for the chalk companies).
This also shows why using chalk is useful. It's not just a traditional thing.
Chalk is not just "useful" ... it is entirely necessary.
I think if you say that the tip contact with cue ball varies only for a very small amount of time, meaning that has no effect on spin, is simply not true. pool is not even a game of milliseconds, millimeters, but a game of even fractions of those. “Having little effect” does not mean no effect, and in pool, it makes a world of difference.
For explanations of why many claims about tip hardness and spin are wrong, see:
billiards.colostate.edu/faq/cue-tip/hardness/
Are you seriously trying to teach drdave about billiard😂😂😂😂😂😂😂😂😂
@@joulupukki1607 you've never been to an academic or professional setting where someone presents their findings, and other ppl ask questions or provide opinions and the conversation goes back and forth, have you?
@@DrDaveBilliards thanks, I'll take a look
That's what I was thinking... It may not stay in contact for a long time, but judging from the slo mo videos, it makes a huge difference in spin.
Edit: after checking out Dr. Dave's link, I guess the only reason it makes more spin is because you can hit further away from center ball without a miscue.
Let's say that I hit with a nickle or dime radius tip. Would hitting with "side spin/english" have any effect on the time the tip stays on the cue ball, compared to hitting straight on?
I suspect there would be small differences, but not of any important consequences. For more info, see:
billiards.colostate.edu/faq/cue-tip/size-and-shape/
Excellent, as usual; your impact on our game from technical study is legendary. I did believe Myth 1 for many earlier decades, but this video evidence is clear. As an artistic billiards player, there seemed no other explanation for the FACT that there are some shots (e.g., extreme bend) that seemingly cannot be made without a VERY long follow-through (a foot or more). I guess the answer must be that such a stroke causes increased acceleration before contact, and avoids any deceleration before contact. It's still a puzzle though, as one would think an 8" follow-through could accomplish both those objectives, but it can't (or at least I can't; with 8" I don't get the extreme action, with 12-14" I do). I have seen some players though who could get unbelievable action with only a medium follow-through -- I guess they're just slamming on the brakes immediately after contact, or their muscle-memory and fast-twitch muscles are better/faster than us mere humans). These observations are still hard to sit happily with the Myth 1 clip.
I'm not sure that I really agree with all of the conclusions from this video. Though the contact time is very short, a softer tip staying in contact for double the time as a break tip would seemingly have an impact on the shot. See massey shots, and why guys go for hard tips on them. Because the ball jumps off the tip cleanly, so you don't double impact the cb.
One way to think of it is like rifle ballistics. The rifling twist of a given barrel, and barrel length will have extreme influences over the ballistics of a bullet fired through that barrel. This is verifiable information, that has been repeatedly reproduced.
It's doubled, but the time is in milliseconds so it's negligible. We can't even perceive that difference in time
@@TimTimTomTom The issues in this video are VERY subtle and technical, and I like to think that someone with a Ph.D. and decades of experience in physics can shed some meaningful light on those subtleties. Pool players as a lot have ingrained "truisms," that we think we know, because we've thought it for years. We then tend to confirm this bias by only listening to, or agreeing with, those things that confirm what we already think. Open your mind to what Dr. Dave says, and follow the evidence of the super slo-mo video. In the hundreds of "new insights" Dr. Dave has offered to our game over many years, I only stubbornly disagree with one (and I'm probably wrong about that).
Also, hard tips aren't used for breaking or massé shots to avoid a double hit -- that's not a problem in either. Harder tips primarily have a greater rebound speed. That's often good for break shots, as well as for massé shots, where it's sometimes hard to gain enough speed for multiple rails with a vertical stroke.
A complete and long follow through is an indicator of a smooth, relaxed, and accelerating stroke with lots of cue speed into the CB. For more info, see:
billiards.colostate.edu/faq/stroke/follow-through/
@@brendanvu1983 not true. When you are talking about differences of 50%, that is not something to ignore. And almost anyone that has gone from a harder tip to a softer tip says they get more action on the cue ball.
Dear Doctor Dave, on the fourth myth, at 4:21, did you mean "noticeable effect" as you said? Or "No noticeable effect" as is implied by your explanation?
Thanks for all the great videos!!
Good catch. I meant to say "no noticeable effect."
FYI, I have a "CORRECTION" in the video description and pinned comment.
Not allowed to jump the cue ball over an obstacle ball? Since when? Who taught me how to play pool. I've only ever played a few dozen games in my life, but never even heard anybody say such a things. If true, this blows my mind.
You are allowed to jump over an obstacle ball, but not with an illegal "scoop" shot:
billiards.colostate.edu/faq/foul/scoop/
I have played enough to know I get better spin with a soft tip vs a hard tip
Many players with lots of experience think this. Any many don't. For more info, see the videos and info in the "Can a softer tip put more spin on the ball?" section here:
billiards.colostate.edu/faq/cue-tip/hardness/
@@tt-tk9076 All the videos and info on this topic can be found here:
billiards.colostate.edu/faq/cue-tip/hardness/
So interesting!!! I mean Kamui seems to disagree with the tip grip by hardness but kinda hard to argue with science
This is not definitive. This just measures contact time, not the surface area. My experience is that a softer tip imparts more spin on the cue ball, and many people agree. I don't care one way or another to be honest, but when I went to a softer tip I got more spin on the ball and a friend, who did not know I had changed my tip, said the same thing when he used my cue.
Explanations for why a softer tip cannot apply more spin can be found here:
billiards.colostate.edu/faq/cue-tip/hardness/
@@DrDaveBilliards Dr Dave thank you for bringing science to the pool world!!
You're welcome. I aim to swerve. :)
4:21 Negligible?
Good catch. I think I meant to say "no noticeable effect."
@@DrDaveBilliards Maybe the "No no" part of it threw you off!
@@kurtkensson2059 Yep. And I thought I checked this one carefully ... twice (because I knew the video might be a little controversial).
@@DrDaveBilliards It does bring up some evidence against things which seem intuitive. Controversy, and discussion, are good for views!
@@kurtkensson2059 Agreed. They are also good for improving knowledge and understanding.
Bob Jewett's studies. He did extensive studies with this. Bob Byrnes says a hard tip applies more English. I have always followed this rule bc physics.
The work Bob did with the Jacksonville Project is fully documented via the resources here:
billiards.colostate.edu/faq/video/jacksonville-project/
I also prefer a hard tip for the reasons here:
billiards.colostate.edu/faq/cue-tip/hardness/
@DrDaveBilliards all great information in the links provided and in the video you posted. I have seen the Jacksonville Project videos and have the documentation stashed away somewhere. Good stuff 👍🏻
Myth 1 - it is called lag time...1ms is a lot. Check out golf physics and the 1000s rpm of spin imparted in far less. Myth 3 - right it varies - yes that makes a huge difference. 2ms is a 100 percent increase on 1 ms. Double the lag-time is huge!
I don't expect people to have looked into this, so a chump video will be all the evidence the averagely physics-educated person will need to be convinced. If you do not know the physics of translational energy vs rotational energy then a visual might be enough for you.
The contact time differences between a hard and soft tip are unimportant per the explanations here:
billiards.colostate.edu/faq/cue-tip/hardness/
FYI, I do know a little about the math and physics of tip/ball collisions and their effect on CB speed and spin. See:
billiards.colostate.edu/technical_proofs/new/TP_A-30.pdf
Question: is it a myth that softer cue tip offers more effects on cue ball and less miss cue ?
The reasons why a softer tip does not impart more spin are explained here:
billiards.colostate.edu/faq/cue-tip/hardness/
Concerning miscues, some hard tips do not always hold chalk as well, and if one doesn't chalk properly, more miscues could occur.
... but miscues are usually caused by bad technique, not bad equipment (tip, chalk, cue, etc.).
Very interesting. I immediately noticed the difference in the 'chalk explosion' between your videos and the Austrian and Russian videos. Looks like the Austrian and Russian videos likely used Master chalk which leaves a dusty mess. Seems obvious your videos were not using Master chalk distinguished by the almost imperceptible chalk explosion at tip contact. I use Taom pyro chalk which isn't a 'dusty' chalk instead leaving very small chunks of chalk on my table. (9ft Gold Crown) What a mess the house cue was. 😁
It is partly the chalk and partly the lighting.
I was always told, and only really seen examples of, that a scoop shot was when you touch the table first then the ball, or both at the same time. quickly googling this now, that's the only example of a scoop shot i see (referencing your site here). but i notice in your example you show the cue hitting the CB first, then the table, then the ball again, and saying it's illegal. is the "true" definition of a scoop shot them "any time the table is touched prior to, or at the same time as, touching the CB even if its after the initial hit?"
That sounds like a fair definition. It doesn’t matter what happens first. A scoop is a scoop. More examples can be found here:
billiards.colostate.edu/faq/foul/scoop/
Just because Ronnie Allen could play winning pool one-handed does not mean I will suddenly improve my game by switching to one-hand pool shots. The problem with anecdotal evidence is that it might be right, or wrong, but we can never know for sure until some basic elements of the scientific method are introduced. Dr Dave has been introducing the science of pool for many years, and has a pretty good track record. I for one thank him for his efforts, and also thank those who assist and carry on his work.
Thank you for the supportive comment.
I noticed from your chart on the cue speed that at impact there is almost no acceleration. The cue is almost at a constant velocity immediately prior to impact. How are your contact times changed by hitting with a cue that is either accelerating or decelerating at the time of the hit? This would seem to be a very important variable. How did you reproduce the stroke to test the different tips? If you did not use some kind of mechanical setup I would have to say that despite the seemingly scientific manner, your study is flawed by not having control over this important variable.
Most good shooters (especially pros) all have very similar stroke speed/acceleration profiles. The cue usually reaches maximum speed very close to tip contact. That's what helps create cue speed with the least effort and consistent speed control. For more info, see:
billiards.colostate.edu/faq/stroke/acceleration/
and:
billiards.colostate.edu/faq/stroke/good-timing/
If a stroke were instead accelerating at impact (not very common) or decelerating at impact (common among many novice or beginner players), there would be slight differences in the tip contact times, but all the trends demonstrated in the video would still apply.