Paging Dr. Dave or other qualified applicants - physics question.

[West Point 1987]

Dr. Dave,

If would be so kind, could you elaborate a bit on #3?

IE increases throw because it has adds to the CIT.

How does IE reduce that throw on larger cut angles?

Thanks in advance should you choose to respond.

Regards to You &

I'd like Dr. Dave's answer, too. As I understand it, slight inside English has a gearing effect on the OB, too, just like outside English. The idea is that a "swiping" CB with no spin has the greatest amount of CIT. Think of the "clinging" effect of the two bodies colliding with each other as they pass. It doesn't seem to make logical sense (the inside spin should create greater friction or cling than a non-spinning CB), but I seem to remember one of Dr. Dave's high speed videos on CIT showing slightly less cling/CIT with either inside OR outside CB spin...I could be mis-remembering it, though.

I'll tell you this...since I started using TOI (about three months ago), I'm amazed at my consistency at most all shots, especially thin cuts down the rail. The CB loses whatever slight spin it has on collision with the OB, then "floats" on a flatter trajectory off the rail, the OB just zooms down and in. I scratch a lot less, too, with little or no fear since the CB isn't influenced by the outside English and running away. CJ shoots several such shots with ease in that video of him beating Mizerak...one in particular is a thin cut to the corner pocket (when I think most that use outside helping English would have shot in the side and come around three rails). He just quickly slices it down to the corner and goes back/forth across table to line up on the next shot. Billy Icardona couldn't keep up with it in his commentary. ("He's making these shots look easy--and they're not"...but with a TOI they are easier than they appear!)

 

[CJ Wiley]

(TOI and the HammerStroke)

I'd like Dr. Dave's answer, too. As I understand it, slight inside English has a gearing effect on the OB, too, just like outside English. The idea is that a "swiping" CB with no spin has the greatest amount of CIT. Think of the "clinging" effect of the two bodies colliding with each other as they pass. It doesn't seem to make logical sense (the inside spin should create greater friction or cling than a non-spinning CB), but I seem to remember one of Dr. Dave's high speed videos on CIT showing slightly less cling/CIT with either inside OR outside CB spin...I could be mis-remembering it, though.

I'll tell you this...since I started using TOI (about three months ago), I'm amazed at my consistency at most all shots, especially thin cuts down the rail. The CB loses whatever slight spin it has on collision with the OB, then "floats" on a flatter trajectory off the rail, the OB just zooms down and in. I scratch a lot less, too, with little or no fear since the CB isn't influenced by the outside English and running away. CJ shoots several such shots with ease in that video of him beating Mizerak...one in particular is a thin cut to the corner pocket (when I think most that use outside helping English would have shot in the side and come around three rails). He just quickly slices it down to the corner and goes back/forth across table to line up on the next shot. Billy Icardona couldn't keep up with it in his commentary. ("He's making these shots look easy--and they're not"...but with a TOI they are easier than they appear!)

Thanks West Point and I'm glad you like the TOI results you're getting.

Roger Griffis (ESPN Ultimate 9Ball Champion) told me I hit those shots better than anyone on earth. I showed him how I do it and told him "now we both do." Roger was around me a lot in my gambling days and we partnered up in a lot of high dollar matches.

Roger gave me one of the best compliments when describing one of our trips, he said: "when I play I'll always bet half of all the money I have, but when CJ plays I'll bet it all" ... he simply knew how much of an advantage I had using the TOI Technique. Roger was an incredible player himself and beat Efren twice in the finals of some major pro tournaments (Sands Regency and HardTimes Open).

My gambling days are past me and even though I'll still play, it's just not "life and death" anymore. I want the "down cycle" to end so much in pool and have committed to helping the Game in any way I can. Sharing my TOI technique I feel is a contribution and will add to any player's enjoyment that honestly tries it for 3 straight hours.

I am adamant about using it EVERY time for a reason and I'll share more about that reason in my TOI Video this weekend. I put all the "TOI CARDS" on the table in the video and I'm looking forward to seeing the sparkle in many eyes. Pool, in my opinion is the "Best Game in the World," designed to be challenging, and also a field of battle to compete to experence both victory and defeat. To experience Life I feel we have to conquer both.

My student tonight said "pool was no fun for me anymore, and now I can't wait to start playing again" (he was using to much spin and didn't have his eyes aligned to his TIP) ... you see I can relate, pool wasn't fun for me when I came back either because I had forgot how important the Touch OF Inside was to my game.

The truth of the matter is I hate to struggle at the game. I want it to be easy and fun, not a struggle filled with uncertainty and volatile confidence.

I appreciate you "WestPoint", you make me feel like it's all worthwhile....showing how I use my techniques has had it's "moments" on AZ FORUM, and I've learned a LOT, grateful to have this opportunity to share my knowledge, it's a "journey, not a destination."

It's taken me thousands of hours to learn these techniques, and I've spilled some "blood, sweat and tears" in this "Pool Journey," - would I do it again? OF COURSE :groucho: I'd do it again, again, and again, and again. 'The Game is the Teacher' CJ Wiley

 

[dr_dave]

For convenience, here's the list of potential benefits of inside English (IE), from the resource page:

1. Some people tend to undercut shots by aiming fuller than the shot requires, and inside english will create squirt that increase the resulting cut angle slightly (although, spin-induced throw will tend to counteract this some).
2. A small amount of IE can counteract the effects of cut-induced spin on the cue ball, possibly resulting in a more natural and predictable rebound angle off a cushion.
3. IE increases throw at small cut angles, but actually reduces the amount of throw at larger cut angles.
4. The amount of throw with IE can be much more consistent than with outside english (OE) if the amount of english varies a little. In other words, the amount of throw varies more with tip placement for OE vs. IE. This might explain why some people prefer using IE on cut shots ... because they can better anticipate and adjust for the amount of throw.
5. The least amount of throw, and the most throw consistency, occurs with fast IE shots.

Regards,
Dave

Dr. Dave,

If would be so kind, could you elaborate a bit on #3?

PJ's answer was good, but I'll add to it.

Let's start with a very small cut angle to the right, but almost straight. With no sidespin, the amount of throw will be very small and to the left slightly. With inside (right) sidespin, the OB will throw to the left a lot more; and with outside (left) sidespin, the CB will throw to the right. So in this case (a small cut angle), inside english obviously increases throw.

With larger cut angles, outside english can create throw either right or left based on whether the amount of english is greater than or less than the "gearing" amount. The following video demonstrates this effect:

HSV B.33 - Outside english gearing, and cut and spin-induced throw​

Inside english always throws the OB in the same direction because the spin is in the CIT direction. However, CIT and SIT don't add as you might think they do. Please look at the following article for an explanation and illustrations:

"Throw - Part VII: CIT/SIT combo" (BD, February, 2007)​

How does IE reduce that throw on larger cut angles?

At small cut angles and small amounts of sidespin, the CB and OB sort of stick together during contact. However, at larger cut angles and/or with lots of inside english, the CB is sliding against the OB during contact. Friction (and therefore throw) is less when the sliding speed is greater. That's why throw is actually less when you add inside with a larger cut angle, because spin increases the sliding speed during contact.

Check out the following video. It demonstrates most of the important throw effects, showing how throw (CIT or SIT) varies with angle, speed, and the amount and direction of spin:

NV B.86 - Cut-induced throw (CIT) and spin-induced throw (SIT), from VEPS IV​

For detailed explanations, illustrations, and examples of all throw-related effects, see the article and video links in items 15-36 under the videos here:

squirt, swerve, and throw effects​

Regards,
Dave

 

[CJ Wiley]

Even on the 10' table the TOI makes hitting the center much easier.

Hate to spoil the party, but here are some "street" results. We had an instructor who was teaching a cueing technique involving inside, adjusting aim for squirt and squirting the ball over on every shot. With english, he was teaching a last minute tip movement.

To make a long story short, his students were so freaking confused their games went down about 30% for a year or two before they realized he was a charlatan and gave up on his dumb ideas.

Now I'm not saying CJ is doing this, since he emphasized only slight off center cueing. This guy was squirting the cue ball a lot!

It's possible to play well cueing off to the side on most shots. It's also possible to play well staying in the center on most shots. Which is less complicated?

Yes, this is not the TOI technique. I assure you it's been kept out of the public eye, and this will become clear after seeing my video on the subject.

I haven't made the strongest case (until the video) about the "TOUCH OF INSIDE" and how it maximizes margin of error in the pocket zone. Hitting the center of the pocket is a result, not an incentive. I consistently hit the center of the pocket, especially on 4 inch pockets.

Even on the 10' table the TOI makes hitting the center much easier. To aim at the center and actually hit it is very difficult and if anyone says it isn't I'll shoot them shot for shot. I used to play people and if I even hit the rail coming into the pocket it didn't count.

Could I do this aiming at the center, using center ball? Not a chance, and neither can anyone else. I'll play anyone in the world and spot them a ball if I can use TOI and they use center ball. This would be a very lopsided, and there's not a pro on earth that would take me up on that offer.

I've been patient with the ones that don't understand the technique without even trying it because I know their "driving force," it's just too bad that their "pride" won't ever let them enjoy the benefits of the TOUCH OF INSIDE system of play. They may even trade in their "virtual pool game," and enjoy the real game of pool. 'The Game is the Teacher'

 

[dr_dave]

I'd like Dr. Dave's answer, too. As I understand it, slight inside English has a gearing effect on the OB, too, just like outside English. The idea is that a "swiping" CB with no spin has the greatest amount of CIT.

That's not true. At small cut angles, the greatest amount of throw will occur with a medium amount of inside english. See my previous post for an explanation.

... I seem to remember one of Dr. Dave's high speed videos on CIT showing slightly less cling/CIT with either inside OR outside CB spin...I could be mis-remembering it, though.

That doesn't sound right to me. Inside increases throw at small cut angles and decreases it at larger cut angles. Outside can either increases or decreases throw based on the amount of spin. Again, see my previous post for explanations and demonstrations.

Regards,
Dave

 

[CJ Wiley]

The pocket sucks it up like it has ESP (EXTRA SUCTION POWER).

PJ...

I'm not saying you're wrong here... but I think CJ is correct. If you aim exactly CB center ball and miss the hitting the center on either side, the CB will "squirt" slightly to either side, opposite the cue tip contact.

If intensionally playing slightly toward the side of CB center ball, the CB will always squirt slightly to the intended side. If you miss toward the CB center line it will go straight to where it was aimed.

With just a touch of inside, the CIT is minimized. Aiming toward the side of the pocket, the OB will either go into the side of the pocket, or be thrown toward the pocket centerline.

That is my conception of what CJ is saying. Carl

This is correct, Carl. The TOI also puts "Pocket Acceptance Spin" (PAS) on the object ball. This is very noticeable when running a shot down the rail. The pocket sucks it up like it has ESP (EXTRA SUCTION POWER). :groucho:

 

[Cornerman]

This is correct, Carl. The TOI also puts "Pocket Acceptance Spin" (PAS) on the object ball. This is very noticeable when running a shot down the rail. The pocket sucks it up like it has ESP (EXTRA SUCTION POWER). :groucho:

"Get In" English!!!

Freddie <~~~ I'd rather not call it anything else

 

[Ralph Kramden]

Thanks West Point and I'm glad you like the TOI results you're getting.

Roger Griffis (ESPN Ultimate 9Ball Champion) told me I hit those shots better than anyone on earth. I showed him how I do it and told him "now we both do." Roger was around me a lot in my gambling days and we partnered up in a lot of high dollar matches.

Roger gave me one of the best compliments when describing one of our trips, he said: "when I play I'll always bet half of all the money I have, but when CJ plays I'll bet it all" ... he simply knew how much of an advantage I had using the TOI Technique. Roger was an incredible player himself and beat Efren twice in the finals of some major pro tournaments (Sands Regency and HardTimes Open).

My gambling days are past me and even though I'll still play, it's just not "life and death" anymore. I want the "down cycle" to end so much in pool and have committed to helping the Game in any way I can. Sharing my TOI technique I feel is a contribution and will add to any player's enjoyment that honestly tries it for 3 straight hours.

I am adamant about using it EVERY time for a reason and I'll share more about that reason in my TOI Video this weekend. I put all the "TOI CARDS" on the table in the video and I'm looking forward to seeing the sparkle in many eyes. Pool, in my opinion is the "Best Game in the World," designed to be challenging, and also a field of battle to compete to experence both victory and defeat. To experience Life I feel we have to conquer both.

My student tonight said "pool was no fun for me anymore, and now I can't wait to start playing again" (he was using to much spin and didn't have his eyes aligned to his TIP) ... you see I can relate, pool wasn't fun for me when I came back either because I had forgot how important the Touch OF Inside was to my game.

The truth of the matter is I hate to struggle at the game. I want it to be easy and fun, not a struggle filled with uncertainty and volatile confidence.

I appreciate you "WestPoint", you make me feel like it's all worthwhile....showing how I use my techniques has had it's "moments" on AZ FORUM, and I've learned a LOT, grateful to have this opportunity to share my knowledge, it's a "journey, not a destination."

It's taken me thousands of hours to learn these techniques, and I've spilled some "blood, sweat and tears" in this "Pool Journey," - would I do it again? OF COURSE :groucho: I'd do it again, again, and again, and again. 'The Game is the Teacher' CJ Wiley

CJ
I'm somewhat confused when you say I am adamant about using it EVERY time.

Are you saying EVERYTIME, or saying every time applicable to the shot you're shooting.
There's no way a mediocre player as myself could play shape using just a TOI everytime. Carl

 

[West Point 1987]

That's not true. At small cut angles, the greatest amount of throw will occur with a medium amount of inside english. See my previous post for an explanation.

That doesn't sound right to me. Inside increases throw at small cut angles and decreases it at larger cut angles. Outside can either increases or decreases throw based on the amount of spin. Again, see my previous post for explanations and demonstrations.

Regards,
Dave

Fair enough, thanks for clearing it up! :smile:

 

[CJ Wiley]

build your "pool shot vocabulary, If I'm wrong, I'll promply admit it

CJ
I'm somewhat confused when you say I am adamant about using it EVERY time.

Are you saying EVERYTIME, or saying every time applicable to the shot you're shooting.
There's no way a mediocre player as myself could play shape using just a TOI everytime. Carl

The reason I suggest this is to build your "pool shot vocabulary," so to speak. It's like reading a book that has words we don't understand and have to look up. It's not only possible, it's easier to use the TOI on EVERY shot, except straight in's and when you have to curve the cue ball or change the angle after contacting a rail.

In all fairness this will become clear after viewing this new TOI video. I explain in much more detail the complete "TOI Package," and how to apply it. With TOI you no longer have to judge SPEED, ANGLE, and CUE BALL TARGET separately, which simplifies the game immensely.

This type training will be great for your level of play, and of course you will have some practice to look forward to. The fun part about this practice is you will learn more in 21 days that you would learn in years of playing the "traditional" way.

I know this is presumptuousness on my part, but after you do it I want you to honestly evaluate whether this statement was correct or not. If I'm wrong, I'll promptly admit it. :thumbup:

 

[CreeDo]

argh. This has turned into another CJ testimonial / bashing thread. I shouldn't have dragged his name into it.

Is anyone qualified and willing to fill in the blanks for a very specific example?
It's basically just a big math problem. There's no reward for doing it other than my gratitude. It'd satisfy my curiosity and give readers a deeper understanding of how accurate tip placement needs to be when using spin on this type of shot.

Lots of people generally know spin has more effect on a fatter hit but I'd love
hard numbers showing exactly how much tip placement errors will over/undercut a given shot.

Here's the math problem if anyone is inclined to tackle it.

CB 1 meter from the OB, cutting 40 degrees, speed 3 meters/s, bridge length .2 meters, BHE, freshly cleaned balls, and if there are any variables I'm forgetting, make up a plausible number for it. Cutting to a pocket on the right. I'm aiming initially to make the ball into the center of the pocket with center ball, without factoring CIT.

Due to CIT, this ball undercuts _ degrees.

If I aim center and accidentally hit 3 mm to the left, the ball overcuts by _ degrees.
If I aim center and accidentally hit 3 mm to the right, the ball undercuts by _ degrees.

If I aim 6 mm of inside and accidentally hit 3 mm, the ball undercuts by _ degrees.
If I aim 6 mm of inside and hit 9 mm, the ball undercuts by _ degrees

If I aim 6 mm of outside and accidentally hit 3 mm, the ball overcuts by _ degrees.
If I aim 6 mm of outside and accidentally hit 9 mm, the ball overcuts by _ degrees.

Also, is the effect linear? If I double the the tip offset, will that double the number of degrees I over/undercut? If not, is there a rule of thumb, like "for every 10 mm of offset, the overcut doubles"?

 

[dr_dave]

argh. This has turned into another CJ testimonial / bashing thread. I shouldn't have dragged his name into it.

Is anyone qualified and willing to fill in the blanks for a very specific example?
It's basically just a big math problem. There's no reward for doing it other than my gratitude. It'd satisfy my curiosity and give readers a deeper understanding of how accurate tip placement needs to be when using spin on this type of shot.

Lots of people generally know spin has more effect on a fatter hit but I'd love
hard numbers showing exactly how much tip placement errors will over/undercut a given shot.

Here's the math problem if anyone is inclined to tackle it.

CB 1 meter from the OB, cutting 40 degrees, speed 3 meters/s, bridge length .2 meters, BHE, freshly cleaned balls, and if there are any variables I'm forgetting, make up a plausible number for it. Cutting to a pocket on the right. I'm aiming initially to make the ball into the center of the pocket with center ball, without factoring CIT.

Due to CIT, this ball undercuts _ degrees.

If I aim center and accidentally hit 3 mm to the left, the ball overcuts by _ degrees.
If I aim center and accidentally hit 3 mm to the right, the ball undercuts by _ degrees.

If I aim 6 mm of inside and accidentally hit 3 mm, the ball undercuts by _ degrees.
If I aim 6 mm of inside and hit 9 mm, the ball undercuts by _ degrees

If I aim 6 mm of outside and accidentally hit 3 mm, the ball overcuts by _ degrees.
If I aim 6 mm of outside and accidentally hit 9 mm, the ball overcuts by _ degrees.

Also, is the effect linear? If I double the the tip offset, will that double the number of degrees I over/undercut? If not, is there a rule of thumb, like "for every 10 mm of offset, the overcut doubles"?

When I can find enough time, I'll try to work out this math for you; although, it is not simple. A thorough analysis would need to consider squirt, swerve, and throw, which depend on other factors not mentioned in your problem statement (e.g., shaft endmass, cue elevation, cloth conditions, etc.). Or do you want me to ignore squirt and swerve and just consider the effects of throw? Let me know, and I'll post something when it is available.

Catch you later,
Dave

 

[Bob Jewett]

... Is anyone qualified and willing to fill in the blanks for a very specific example? ...

It's awesome that Dr. Dave offered to fill in the blanks, but there are two much better ways for you to answer the question by yourself.

Read my column titled "Forced Accuracy" mentioned above and repeat the experiment for the conditions you pose. This is a much better way for you to learn than reading the numerical results on your computer screen. You may learn lots of other stuff at the same time.

Way II: get Virtual Pool. Turn on "Tracking". Wiggle the stick back and forth and see where the object ball goes. VP includes squirt, swerve, and throw. And the effects of speed. You can do all sorts of experiments and then try the same things on the table and get nearly the same results. Some versions of VP allow you to vary newness of the cloth and such.

 

[dr_dave]

It's awesome that Dr. Dave offered to fill in the blanks, but there are two much better ways for you to answer the question by yourself.

Read my column titled "Forced Accuracy" mentioned above and repeat the experiment for the conditions you pose. This is a much better way for you to learn than reading the numerical results on your computer screen. You may learn lots of other stuff at the same time.

Way II: get Virtual Pool. Turn on "Tracking". Wiggle the stick back and forth and see where the object ball goes. VP includes squirt, swerve, and throw. And the effects of speed. You can do all sorts of experiments and then try the same things on the table and get nearly the same results. Some versions of VP allow you to vary newness of the cloth and such.

Excellent suggestions! I agree completely that careful experiments at the table (or with well-written simulator software) are much more fun and educational than a math and physics analysis.

Regards,
Dave

 

[Ralph Kramden]

The reason I suggest this is to build your "pool shot vocabulary," so to speak. It's like reading a book that has words we don't understand and have to look up. It's not only possible, it's easier to use the TOI on EVERY shot, except straight in's and when you have to curve the cue ball or change the angle after contacting a rail.

In all fairness this will become clear after viewing this new TOI video. I explain in much more detail the complete "TOI Package," and how to apply it. With TOI you no longer have to judge SPEED, ANGLE, and CUE BALL TARGET separately, which simplifies the game immensely.

This type training will be great for your level of play, and of course you will have some practice to look forward to. The fun part about this practice is you will learn more in 21 days that you would learn in years of playing the "traditional" way.

I know this is presumptuousness on my part, but after you do it I want you to honestly evaluate whether this statement was correct or not. If I'm wrong, I'll promptly admit it. :thumbup:

I guess the word EXCEPT answered my question in my #28 post. Thanks... http://www.youtube.com/watch?v=AX8peO0OQh0

 

[ENGLISH!]

Let's start with a very small cut angle to the right, but almost straight. With no sidespin, the amount of throw will be very small and to the left slightly. With inside (right) sidespin, the OB will throw to the left a lot more; .... So in this case (a small cut angle), inside english obviously increases throw.

Inside english always throws the OB in the same direction because the spin is in the CIT direction. However, CIT and SIT don't add as you might think they do.

At small cut angles and small amounts of sidespin, the CB and OB sort of stick together during contact. However, at larger cut angles and/or with lots of inside english, the CB is sliding against the OB during contact. Friction (and therefore throw) is less when the sliding speed is greater. That's why throw is actually less when you add inside with a larger cut angle, because spin increases the sliding speed during contact.

Regards,
Dave

Dr. Dave,

First, thanks for the elaborated explanation.

Here's a bit of confusion, as I see it. You have changed the parameters by applying differing amounts of spin to the different cut angles. And it seems that you are referring to CIT only in the conclussion because the increased spin/speed reduces the friction per less contact time.

What, if any, would be the different amounts of total throw, collision & spin, be if the spin/speeds were reduced to an equal amount, say, slow spin/speed for both slight & increased angles?

Again, thanks in advance, Best Regards &

 

[CreeDo]

Bob: Virtual pool is neat, and maybe it has perfect simulated physics (I'm skeptical).

But what I'm looking for is a hard number saying how many degrees the cut is affected. I'm not sure the software will let me dial in a cut angle of exactly 40 degrees, nor inform me of the resulting cut angle after I applied my chosen spin. It will just give me a visual representation of what happened after I hit the ball. At best I might be able to see that the ball went towards one side of the pocket rather than the expected center of the pocket.

I also can't tell what 3mm of spin looks like on a computer screen, vs. 9mm, and does it simulate BHE?

As far as getting to a table and just trying it myself, I can't hit balls the same way every time. Variations in speed, tip placement, pivot, and other conditions will affect the results. And I probably can't tell from the shooting position what a half degree off looks like, if the effect is that small.

You could argue that if my imperfect stroke means I can't be that precise, then it doesn't matter. But it does. I'd like to know how much precision is required, before I decide whether that level of precision is something I can reasonably pull off.

Dave: If you have the time and are willing, it would be awesome. For the missing variables... if you ignore them, will the results still be reasonably close to accurate? If so then we can skip 'em. If you think they matter though... maybe you could plug in some typical figures?

 

[dr_dave]

PJ's answer was good, but I'll add to it.

Let's start with a very small cut angle to the right, but almost straight. With no sidespin, the amount of throw will be very small and to the left slightly. With inside (right) sidespin, the OB will throw to the left a lot more; and with outside (left) sidespin, the CB will throw to the right. So in this case (a small cut angle), inside english obviously increases throw.

With larger cut angles, outside english can create throw either right or left based on whether the amount of english is greater than or less than the "gearing" amount. The following video demonstrates this effect:

HSV B.33 - Outside english gearing, and cut and spin-induced throw​

Inside english always throws the OB in the same direction because the spin is in the CIT direction. However, CIT and SIT don't add as you might think they do. Please look at the following article for an explanation and illustrations:

"Throw - Part VII: CIT/SIT combo" (BD, February, 2007)​

At small cut angles and small amounts of sidespin, the CB and OB sort of stick together during contact. However, at larger cut angles and/or with lots of inside english, the CB is sliding against the OB during contact. Friction (and therefore throw) is less when the sliding speed is greater. That's why throw is actually less when you add inside with a larger cut angle, because spin increases the sliding speed during contact.

Check out the following video. It demonstrates most of the important throw effects, showing how throw (CIT or SIT) varies with angle, speed, and the amount and direction of spin:

NV B.86 - Cut-induced throw (CIT) and spin-induced throw (SIT), from VEPS IV​

For detailed explanations, illustrations, and examples of all throw-related effects, see the article and video links in items 15-36 under the videos here:

squirt, swerve, and throw effects​

Dr. Dave,

First, thanks for the elaborated explanation.

You're welcome.

Here's a bit of confusion, as I see it. You have changed the parameters by applying differing amounts of spin to the different cut angles. And it seems that you are referring to CIT only in the conclusion because the increased spin/speed reduces the friction per less contact time.

Friction and throw are not reduced due to less contact time, they are reduced when the speed of sliding between the ball surface is faster during contact. This occurs with larger cut angles. It also occurs when you add more inside english.

What, if any, would be the different amounts of total throw, collision & spin, be if the spin/speeds were reduced to an equal amount, say, slow spin/speed for both slight & increased angles?

With a small cut angle, a small to medium amount of inside english will increase throw, but a large amount of inside will actually decrease throw. With larger cut angles, any amount of inside english will reduce throw.

If you haven't watched the videos yet, check them out. They might help. Also, the following articles cover this stuff fairly well:

"Throw - Part VI: inside/outside english" (BD, January, 2007)
"Throw - Part VII: CIT/SIT combo" (BD, February, 2007)​

Check them out.

Regards,
Dave

 

[ENGLISH!]

Dr. Dave,

Thanks again. The graphs were helpful and easier than deciphering the language vernacular. I think they might be exactly that for which Mr. CreeDo is looking.

They say men are visual beings. Your lines were a little too straight for my liking. I prefer curved lines resembling that of an hour glass.:wink:

I believe it has been my & others' experience that slow inside combination english, especially with low in close quarters will result in considerable throw, enough to cause a mis if not aimed to compensate. Certainly it is far less than 25% of maximum spin.

That is why it is so difficult for a generalized statement to be fully agreed upon when different minds are in different places with different parameters in mind. The result certainly can be a miscommunication. The world's biggest problem.

Best Regards &

 

[dr_dave]

Dr. Dave,

Thanks again. The graphs were helpful and easier than deciphering the language vernacular. I think they might be exactly that for which Mr. CreeDo is looking.

If you like throw graphs, check out all of the plots here:

TP A.28 - Throw plots for all types of shots
TP B.3 - Throw calibration and contour plots for various cut angles, speeds, English, and roll​

They answer pretty much any conceivable question concerning throw and how it changes with shot speed, cut angle, amount and type of sidespin, and the amount of top or bottom spin.

Creedo can probably find the answers to his questions here also.

Let me know if you or others need help deciphering how to read the graphs or interpret the results.

Regards,
Dave