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adr147
May26-07, 09:45 AM
ok - a question for you boffins out there!

playing snooker / pool, will a smaller or larger tip generate more spin?

logic tells me that the point of contact is larger on a larger tip but that the time in contact with the white is greater with a smaller tip. which matters more? (i know as a player the answer is the smaller tip but i would like to know why!)

Danger
May26-07, 10:51 AM
Welcome to PF, Adr. I used to use an 11mm tip for years, and was irritated that my new stick was available only with 12 or 13. A couple of my more professional friends (one's a ref; one an instructor) insisted that a larger tip was better. Now that I'm used to my 12, I tend to agree. I can see the logic of it. For a given amount of offset on the cue ball, there is more of the tip in contact, as you mentioned. The duration of that contact has nothing to do with the tip size; it's all in the stroke. Of far more importance is the material of the tip. You'll get the most grab from a very soft one, but they don't last very long. A hard one can last a couple of seasons, but doesn't hold chalk very well and can tend to skid off of the ball. Most of us around here use Elkmaster medium hardness, which is a really good compromise.

pixel01
May26-07, 10:56 AM
Theoretically, it does'nt depend on how large the tip is. Because spinning depends on the friction force, the friction force in turn depends only on the tip's roughness, not its area.

adr147
May26-07, 10:59 AM
for american pool 12mm would be my choice (talisman soft not an elkmaster!) - i am aware of the materials issue etc and have to say i play to a high standard and sell the equipment for a living but given the following were the case which would generate more spin?

the cues are identical
the distance the cue travels through the shot is the same
and its speed and angle are also identical
so the only variable is the tip size and shape. (a smaller tip by its nature will be more rounded)

adr147
May26-07, 11:01 AM
Theoretically, it does'nt depend on how large the tip is. Because spinning depends on the friction force, the friction force in turn depends only on the tip's roughness, not its area.


so its the same, but we find it easier with a smaller tip? - the firmness of the tip makes a big difference the softer the tip the easier it is to generate spin.

pixel01
May26-07, 11:07 AM
so its the same, but we find it easier with a smaller tip? - the firmness of the tip makes a big difference the softer the tip the easier it is to generate spin.

I said theoretically.
You are right when saying the softer the tip, the better, because that softness plays a buffer role for the tip to 'grip' better to the ball. So may be the smaller tip is a little bit softer and that answers your question.

Danger
May26-07, 11:07 AM
I beg to differ. The contact area does affect the friction force. Obviously, every mm^2 has a certain amount of friction. The more mm^2, the more friction.

edit: You guys slipped in a couple of extra posts while I was composing this. I've never heard of Talisman; where are you, Adr?

adr147
May26-07, 11:09 AM
I beg to differ. The contact area does affect the friction force. Obviously, every mm^2 has a certain amount of friction. The more mm^2, the more friction.


so assuming the tips are of the same hardness where are we now!! - my physics is not up to this but i KNOW from playing its easier with a smaller tip.

pixel01
May26-07, 11:15 AM
I beg to differ. The contact area does affect the friction force. Obviously, every mm^2 has a certain amount of friction. The more mm^2, the more friction.

edit: You guys slipped in a couple of extra posts while I was composing this. I've never heard of Talisman; where are you, Adr?

No, I don't think so. Friction force = Force*C (C is the dynamic friction constant). The force here depends on how strongly you push the ball and the ball's weight.

adr147
May26-07, 11:16 AM
No, I don't think so. Friction force = Force*C (C is the dynamic friction constant). The force here depends on how strongly you push the ball and the ball's weight.


i am in scotland - you?

all other factors remain constant, cue ball weight etc.

pixel01
May26-07, 11:21 AM
I am in the Netherlands. I just play snooker now and then and not good enough to see the difference in tip size.
If you say all other factors remain constant, I should say the softer the tip, the better because logically, it is softer and then easier to grab the cue.

adr147
May26-07, 11:22 AM
but we need to assume that the hardness of both sizes is the same.

pixel01
May26-07, 11:25 AM
So again, they are the same theoretically. Just one thing I can guess : the smaller the tip, the better for the player to hit exactly at the point he wants. And that is the advantage.

adr147
May26-07, 11:29 AM
So again, they are the same theoretically. Just one thing I can guess : the smaller the tip, the better for the player to hit exactly at the point he wants. And that is the advantage.

this was my thought but i am not sure the physics prove it.

neurocomp2003
May26-07, 11:30 AM
does tip thickness have any relation to weight class of the cue?

It could also be a psychological thing...some epeople feel more comfortable with the aim of a smaller cue..OThers like putting more power with a thicker cue.

May also be dependent on the ball size, since if i remmeber correctly snooker plays with a smaller radius on the ball.

pixel01
May26-07, 11:32 AM
The physics is just above: dynamic friction force does not depend on the surface area.
And with smaller tip, surely you can have more points on the cue to hit (this may not be physics).

adr147
May26-07, 11:33 AM
does tip thickness have any relation to weight class of the cue?

It could also be a psychological thing...some epeople feel more comfortable with the aim of a smaller cue..OThers like putting more power with a thicker cue.

May also be dependent on the ball size, since if i remmeber correctly snooker plays with a smaller radius on the ball.

again we would have to say they tips have the same thickness although in reality thats not likely and i suppose you would automatically make the smaller tip softer if it were the same thickness.

its definately easier to aim at the point you need so mentallly thats a done deal.

a snooker ball is 2.25" so yes its smaller - as are the pockets but the table is a lot bigger!

adr147
May26-07, 11:42 AM
another thought - the smaller tip is in contact with the cue ball for longer as you push through the shot so has less of a 'slapping' effect on the cue ball?

Danger
May26-07, 11:42 AM
I have to leave for work now; I'll log back in when I get there (unless some damned client shows up). In the meantime, I'm in Canada, near Calgary. From my personal experience, I find a larger tip to be better in this matter. I was about to mention the aiming aspect before you guys beat me to it. I can't do that 'line your chin up with the cue' crap; I sight down the cue like a rifle. It was indeed my problem in switching to a wider tip that it took a while to extrapolate the edge contact as referenced from the centreline of the stick. I had the same problem when we switched from using an oversize cueball to one that's the same size as the object balls. Be back in a bit.

adr147
May26-07, 11:48 AM
I have to leave for work now; I'll log back in when I get there (unless some damned client shows up). In the meantime, I'm in Canada, near Calgary. From my personal experience, I find a larger tip to be better in this matter. I was about to mention the aiming aspect before you guys beat me to it. I can't do that 'line your chin up with the cue' crap; I sight down the cue like a rifle. It was indeed my problem in switching to a wider tip that it took a while to extrapolate the edge contact as referenced from the centreline of the stick. I had the same problem when we switched from using an oversize cueball to one that's the same size as the object balls. Be back in a bit.


lol - i think we will not get to the bottom of this there are too many variables.

Danger
May26-07, 12:14 PM
That is entirely possible. All that I can say is that from personal experience, I can get a lot more juice on the ball with the 12 than I could with the 11. Tip thickness and hardness are identical. (Some idiot sold me a diamond tip rather than a medium once, and it literally wore out my shaper while I was trying to scuff it up enough to hold chalk. :grumpy:)

adr147
May26-07, 12:15 PM
That is entirely possible. All that I can say is that from personal experience, I can get a lot more juice on the ball with the 12 than I could with the 11. Tip thickness and hardness are identical. (Some idiot sold me a diamond tip rather than a medium once, and it literally wore out my shaper while I was trying to scuff it up enough to hold chalk. :grumpy:)


LOL - TRY A TALISMAN BUFFALO IN HARD GRADE ITS LIKE GLUEING HALF A MARBLE TO YOUR CUE!

Danger
May26-07, 12:23 PM
:surprised
No, thanks. :bugeye:

adr147
May26-07, 12:32 PM
:surprised
No, thanks. :bugeye:

lol very wise - or just remove the tip altogether and shape the end of the cue it would have a similar effect!

jambaugh
May26-07, 12:37 PM
ok - a question for you boffins out there!

playing snooker / pool, will a smaller or larger tip generate more spin?

logic tells me that the point of contact is larger on a larger tip but that the time in contact with the white is greater with a smaller tip. which matters more? (i know as a player the answer is the smaller tip but i would like to know why!)

All the comments about tip size itself are ok but the main issue is that for thinner and more flexible shafts you get a whipping action which increases the amount of spin you put on the cue ball. So it is not just a property of the diameter but also the materials used to make the shaft.

As far as frictional effects go, tip size is relatively unimportant. Just make sure the tip is soft enough, round enough, and well chalked to maintain good contact. Without considering shaft flex the "english" you obtain is purely a function of how far off center you strike the ball and how hard the ball is struck.

Flex does two things, it increases the contact time and it allows the tip to roll along with the ball so through part of the contact period the tip moves farther off center imparting spin more effectively.

Regards,
James Baugh,

P.S. I worked up a nice little analysis of the Masse shot. In the idealized case the angle that the ball turns off its initial pass is purely a function of where it is struck and how much down-angle you apply. I had a sudden inspiration while shooting and realized felt quality only matters with respect to how quickly the spin takes effect and not the degree of turn.
R.
J.B.

adr147
May26-07, 12:49 PM
in snooker how hard you strike the ball will not change how much it spins - only cueing further through it will ?

Danger
May26-07, 12:49 PM
Good post, Jambaugh. The only problem that I have with the 'whiplash' effect of a flexible shaft is that it also tends to slap the ball in the direction opposite to the imparted spin. That not only sends it in the wrong direction, but also increases the likelihood of a miscue. That's one reason that Predator cues (and to a lesser extent my Steel Stick) are designed to be rigid.

edit: Adr, you sneaked in again. The harder you hit the ball, the less effect the spin will have. Keep in mind that the ball always travels in the same direction that it's 'facing' before deflecting. The harder you hit it, the farther it goes before the spins kicks in. The same applies to an object ball after being struck by the cue ball.

edit#2: Okay, I've been at work for an hour, and nothing has happened. I'm going to close up for 10 minutes and go buy some beer for lunch. Back shortly.

edit#3: By the bye, I was going to mould myself a tip out of silicone sealant so that I'd never have to shape it or chalk it. Unfortunately, the regulations stipulate that it has to be 'leather or a leather-like material'. :grumpy:

jambaugh
May26-07, 02:50 PM
ard147: Not quite correct. The harder you strike the ball the more spin but the ratio between "spin"=angular momentum and linear momentum will be the same.
Hence the effect of the spin with respect to the cue deflecting on a bank will be unchanged. In fact I think most effects will be functions only of this ratioL/P. Where it will make a difference is when you have dissipation of momentum due to rolling friction distinct from dissipation of angular momentum due to contact friction. These differences are too small to worry about excepting in certain very long shots and certain very short shots.

To Danger: Your point about the farther a ball goes before spin kicks in matters for draw and follow (an masse) but not for side-spin. Also I know a guy who fashoned a neoprene tip from a "superball". He said it gave him outstanding power on breaks but if I remember correctly he said it didn't affect spin as much... then again he isn't as well versed on the use of spin effects.

To All: I was looking for the file where I typed up the masse physics. If I find it I will post a link to it.

adr147
May26-07, 03:11 PM
Good post, Jambaugh. The only problem that I have with the 'whiplash' effect of a flexible shaft is that it also tends to slap the ball in the direction opposite to the imparted spin. That not only sends it in the wrong direction, but also increases the likelihood of a miscue. That's one reason that Predator cues (and to a lesser extent my Steel Stick) are designed to be rigid.

edit: Adr, you sneaked in again. The harder you hit the ball, the less effect the spin will have. Keep in mind that the ball always travels in the same direction that it's 'facing' before deflecting. The harder you hit it, the farther it goes before the spins kicks in. The same applies to an object ball after being struck by the cue ball.

edit#2: Okay, I've been at work for an hour, and nothing has happened. I'm going to close up for 10 minutes and go buy some beer for lunch. Back shortly.

edit#3: By the bye, I was going to mould myself a tip out of silicone sealant so that I'd never have to shape it or chalk it. Unfortunately, the regulations stipulate that it has to be 'leather or a leather-like material'. :grumpy:

i hit further through the ball and lower down in order to generate more backspin and i can without hitting it any harder screw it back the full length of a snooker table.

you can buy tips made of rubber that need no chalk and last forever but they are sh!te!

Danger
May26-07, 03:17 PM
Damn, but I am enjoying discussing this with fellow players!
I don't know whether or not there is a particular amount of curvature and/or reversal that determines whether or not a shot is a masse. I regularly curl the cue ball around another by using just side and bottom spin with my stick still as parallel to the table as I can get it. I always considered that to be a masse, and it definitely doesn't work if you strike hard.
As to the cue-off-of-the-bank scenario, the rail itself alters the trajectory. If you hit the cue ball into the rail at moderate power, it will rebound at approximately a mirror-image angle (assuming no side-spin). The harder you hit it, the less angle you get. The rail compresses under the impact, then springs outward to its normal shape. That pushes the ball at 90 degrees to the rail in addition to the normal rebound, so it actually underbanks.

edit: Dammit! Will you stop sneaking in while I'm composing? :grumpy::biggrin:
The follow-through on any shot should be around 6"; the placement and angle determine the result. The execption to that is on the break shot, where you should be trying to put your stick through the rack. (Not in snooker, of course, but my primary game is Valley Rule/BCA 8-Ball.)
As for the rubber tips, however, the rules definitely still prohibit them.

adr147
May26-07, 03:20 PM
i don't play the same game but the plays is the same! but have you ever seen a twister tip ? - it makes masse shots stupidly easy! i suspect a decent snooker player might suprise an american pool player!

Danger
May26-07, 03:31 PM
I have not only never seen a twister tip, I've never even heard of one. What the hell is it? I bet that it's still illegal, though.
And, in actual fact, the plays are not the same. I do play snooker upon occassion, and enjoy it very much, but it's vastly different. To start with, the pockets are a different shape, so some of my favourite shots won't work on a snooker table. More important, though, is that those golf-ball size suckers don't have anything like the angular momentum I'm used to from 8-ball.
And I know that lots of things can surprise a Yank player. I, as a Canuk, am one of them. :biggrin:

adr147
May26-07, 03:35 PM
stop editing back - i am always reading the last post! - i just checked my follow through and its about 6" most shouts and about 7.5" for a deep screw shot. never heard of the first game but i have won a few 8 ball competitions. http://www.shop.uk8ball.co.uk/product_info.php?products_id=345

Danger
May26-07, 03:44 PM
stop editing back - i am always reading the last post!

Nobody's fault but your own. :tongue:
Okay, I'm just trying to save bandwidth. I'll start a new post from now on. For the nonce, though, I have to go and perform one or two of my duties since I'm still at work. I won't bother logging out this, time, though, so don't be offended if I don't respond when I'm shown on-line. Later, dude.
That tip, by the way, is definitely illegal.

adr147
May26-07, 03:46 PM
Nobody's fault but your own. :tongue:
Okay, I'm just trying to save bandwidth. I'll start a new post from now on. For the nonce, though, I have to go and perform one or two of my duties since I'm still at work. I won't bother logging out this, time, though, so don't be offended if I don't respond when I'm shown on-line. Later, dude.
That tip, by the way, is definitely illegal.

illegal, i suspect so, but fun! - work, oh yes i remember that - its that thing other people do!

jambaugh
May26-07, 03:50 PM
Damn, but I am enjoying discussing this with fellow players!
I don't know whether or not there is a particular amount of curvature and/or reversal that determines whether or not a shot is a masse.

I used to think masse referred to the extreme case and I would call "gentle masses" curve shots, or in my own vernacular "scooching the ball". But in reading on the topic it seems the consensus is that any axial spin induced curving of the rolling ball's path is a masse.

Regards,
James Baugh
P.S. I only have a partial file of the masse physics here at home. The full file is on my PC in my office. But it is in MSWord format and so I think I'll transcribe it to Latex and make some clarifying edits along the way.
R. JB.

adr147
May26-07, 03:55 PM
masse is not a term we use here we call it a swerve. swerves come in various sizes and the bigger they are the less likely you are to make the shot!

Danger
May26-07, 04:48 PM
Well, apparently 'swerve' and 'masse' are the same thing. I've often wondered why a game devised in Britain would have a French word associated with it.

work, oh yes i remember that - its that thing other people do!
Hey, I only do it so I can buy cat food for Lucy.

adr147
May26-07, 05:08 PM
Well, apparently 'swerve' and 'masse' are the same thing. I've often wondered why a game devised in Britain would have a French word associated with it.


Hey, I only do it so I can buy cat food for Lucy.

i think billiards which was the first cue sport came from france about 600 years ago? but then the whole english language has latin to french to english as one of its origins.

is lucy your wife or a cat?

Danger
May26-07, 05:16 PM
My cat, but she and W sometimes fight over the food. :biggrin:

Okay, my work day is over. I'm going to log off to do my cashout and go home. Back in 20 or so.

adr147
May26-07, 05:22 PM
well i am off to the pub to think about pool shots over a few beers!

adr147
May26-07, 08:22 PM
beer is a wonderful thing - really brings out the physics!

Danger
May26-07, 09:11 PM
Sorry, I got distracted by a couple of neighbours partying on the lawn, and then by a steak that needed attention, and by a few more beers, and...
...I just got started posting this, and got hailed through the balcony window by my neighbour (who, incidentally, bears no resemblance to Romeo) to come out on the lawn for some beers. I love PF, but I also love beer, so... see ya...

Dallas147
May30-07, 07:07 AM
Hey Ladies
I am the instigator of this subject from a snooker forum in Australia. The funny part about it, it was a joke topic for me. LOL!!

ps: is it still impossible for a bumble-bee to fly?

adr147
May30-07, 08:09 AM
Hey Ladies
I am the instigator of this subject from a snooker forum in Australia. The funny part about it, it was a joke topic for me. LOL!!

ps: is it still impossible for a bumble-bee to fly?

hey dallas - we hijacking a physics forum now, these guys don't deserve that! - of course a bumble bee can fly, just not fast enough to stop you kicking them!

Dallas147
May30-07, 08:43 AM
Yes, well i see your trying for a 100 posts here to..

Danger
May30-07, 09:11 AM
it was a joke topic for me. LOL!!
While it might have been a joke to start with, it is actually a very interesting subject with a firm grounding in physics and is perfectly acceptable to the forums.
From a pool perspective, just think of how many non-players are reading this and might be encouraged to take up the game because of it.
Adr, you can't hijack a PF forum; only someone else's thread. Since you started this thread, there's no pirating involved. Were it contrary to forum guidelines, it would be locked or deleted.

ps: is it still impossible for a bumble-bee to fly?
The little bastards have always been able too. Early scientists didn't have the instrumentation to realize that the twisting motion of their wings imparts wingtip vortices that vastly increase the lift factor. :tongue:

Dallas147
May30-07, 09:40 AM
Well, there you go...

Dallas147
May30-07, 09:43 AM
Anyway, bigger tip, more spin...

adr147
May30-07, 09:45 AM
While it might have been a joke to start with, it is actually a very interesting subject with a firm grounding in physics and is perfectly acceptable to the forums.
From a pool perspective, just think of how many non-players are reading this and might be encouraged to take up the game because of it.
Adr, you can't hijack a PF forum; only someone else's thread. Since you started this thread, there's no pirating involved. Were it contrary to forum guidelines, it would be locked or deleted.


The little bastards have always been able too. Early scientists didn't have the instrumentation to realize that the twisting motion of their wings imparts wingtip vortices that vastly increase the lift factor. :tongue:


ok now we really are getting technical! - 100 posts a way off here!

Danger
May30-07, 09:46 AM
Well, there you go...

And according to Simpson's First Law of Location... no matter where you go, there you are. :biggrin:

adr147
May30-07, 09:50 AM
And according to Simpson's First Law of Location... no matter where you go, there you are. :biggrin:


andrew's law of motion:

the speed at which you can run is directly proportional to the size of your pursuer!

Danger
May30-07, 09:51 AM
ok now we really are getting technical! - 100 posts a way off here!

Okay, I'm not back-editing because you asked me not to, but once again you sneaked in while I was composing (jeez, I just mistyped that as composting, but I caught it in time).
Technical is what we do here. What were you expecting?

And if you're really desperate for posts, you can have some of mine. I've got so many of the damned things that I don't know what to do with them any more. All of the closets are full, W started stacking them up in the furnace room, there are a few kicking around on the lawn...

Danger
May30-07, 09:52 AM
You are really tempting me to start back-editing again. Good quote, though. :biggrin:

adr147
May30-07, 09:54 AM
Okay, I'm not back-editing because you asked me not to, but once again you sneaked in while I was composing (jeez, I just mistyped that as composting, but I caught it in time).
Technical is what we do here. What were you expecting?

And if you're really desperate for posts, you can have some of mine. I've got so many of the damned things that I don't know what to do with them any more. All of the closets are full, W started stacking them up in the furnace room, there are a few kicking around on the lawn...


yes but imagine this, i have lost count of the number of forums i am signed up to!! - my e-mail inbox gets e-mails 24 hours a day at about 20/30 per hour of which only half are related to work!

adr147
May30-07, 09:55 AM
You are really tempting me to start back-editing again. Good quote, though. :biggrin:

type quicker!
:tongue:

adr147
May30-07, 09:56 AM
You are really tempting me to start back-editing again. Good quote, though. :biggrin:

actually is not a quote is my own work - during a physics class aged 15 !!! i think i had about 20 of them in the end!!

Danger
May30-07, 10:09 AM
Hey, I used to be able to type 120 wpm on a real typewriter. Computer keyboards are too sensitive, so it slows me down. So does the arthritis. In this case, though, it's because I'm doing other things at the same time.

And even if you made it up, it's now a quote. Others will borrow it, and soon the net will be so cluttered with it that we'll all be sick of if. :biggrin:

adr147
May30-07, 10:42 AM
Hey, I used to be able to type 120 wpm on a real typewriter. Computer keyboards are too sensitive, so it slows me down. So does the arthritis. In this case, though, it's because I'm doing other things at the same time.

And even if you made it up, it's now a quote. Others will borrow it, and soon the net will be so cluttered with it that we'll all be sick of if. :biggrin:

120 an hour would be hard for me!! - its a bad habit we all have of doing several things at once!

prasannapakkiam
May31-07, 04:41 AM
Okay. Here is my say:

In cricket, spin is achieved when the ball is in contact with the ground for a maximum amount of time - thus moist pitches and 'flighting the ball' helps. So I would think a larger tip would stay in contact with the ball for a longer period of time. This creates maximum time of contact for a good spin to occur...

adr147
May31-07, 06:40 AM
Okay. Here is my say:

In cricket, spin is achieved when the ball is in contact with the ground for a maximum amount of time - thus moist pitches and 'flighting the ball' helps. So I would think a larger tip would stay in contact with the ball for a longer period of time. This creates maximum time of contact for a good spin to occur...


a larger tip is in contact for less time - a bigger tip has more of a slapping effect.

prasannapakkiam
May31-07, 05:45 PM
Then it is the smaller tip (I do not play Snooker much), anyway it is all about the time spent in contact.

adr147
May31-07, 07:21 PM
Then it is the smaller tip (I do not play Snooker much), anyway it is all about the time spent in contact.

maybe, although many people on here much brighter than me say it makes no difference!

prasannapakkiam
May31-07, 07:45 PM
Read the book on "Physics of Ball Games". It states in Snooker, such collisions are almost elastic, thus the difference in time in contact is negligible. The only thing REALLY affecting spin, is the position upon which the ball was hit upon.

adr147
May31-07, 07:49 PM
Read the book on "Physics of Ball Games". It states in Snooker, such collisions are almost elastic, thus the difference in time in contact is negligible. The only thing REALLY affecting spin, is the position upon which the ball was hit upon.

this is the point of the question! - i was hoping that someone on here would be able to give me a solid answer and all i have now are more questions!!!

Danger
May31-07, 08:10 PM
Look at it this way:
You can initially consider the tip and the ball to be spheres of different radii. If neither deformed, there would be a single point of contact as with other spheres. The larger tip has a larger radius than the small tip. Since it does flatten under impact, that radius results in more deformed surface area in contact.
Anyhow, as I said before, personal experience indicates that the larger tip is superior for juicing the ball.

adr147
Oct24-07, 08:07 PM
now you see months later and still no-body has proved to me in scientific terms which is better, where else can i find this information if not on a physics forum!!!:smile: (hint - i know as a player the answer is smaller, what i don't know is why, and by the way some of the top players in the world are waiting on snooker and pool forums for an answer!)

jambaugh
Oct25-07, 09:13 AM
One other factor is that the tip mass will effect a deflection of the cue ball when you strike off center (i.e. apply side spin). That is to say instead of the cue ball going exactly in the direction of your stroke, it will bounce slightly to the side. The lighter the tip the less this will occur. Smaller usually means lighter in this case. For all I know that is the main issue.