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View Full Version : Shaft end mass, deflection and snooker cues: Calling Science Guys


mnorwood
06-18-2009, 09:51 PM
It is a well established fact that deflection depends on the mass of the end of the shaft on any given cue.

Snooker shafts have smaller diameters which would logically mean that the end mass is lighter.

So the question is shouldn't snooker shafts be low deflection? Or does the brass ferrule make it heavier?

If the shaft is low deflection what are the drawbacks for hitting pool balls with snooker cues?

Cameron Smith
06-18-2009, 11:06 PM
Just to get the ball rolling as I am no science guy,

Yes there is certainly less deflection. I've played pool with my parris cue a couple of times and each time I was pocketing with ease while cueing terribly. If I was on a snooker table, I wouldn't have been potting anything.

But I was getting far more spin than I was use to and over hitting everything. My position play was way off. But I don't see that as being a draw back so much since I am not used to play pool with my parris. I'm sure if I switched exclusively to a snooker cue I would get used to it.

I'm sure there has to be a reason as to why pool cues still have larger tips. I'm curious to hear from some cue makers.

Donkey Puncher
06-19-2009, 12:17 AM
Snooker cue shafts are made of ash which is a much more rigid wood, so they wouldn't really be low deflection at all. Yes, tip end mass has a lot to do with it, but there are other factors.

If you hit a cueball with English (or side) with a very light shaft of titanium, do you think it would deflect , or squirt, the cue ball or not? If the shaft cannot bend out of the way during contact, then there would be a much higher deflection.

Therefore, NO, snooker shafts are not low deflection shafts at all. They would be much worse, however, if they were thicker.

Rich93
06-19-2009, 12:50 AM
Snooker cue shafts are made of ash which is a much more rigid wood, so they wouldn't really be low deflection at all. Yes, tip end mass has a lot to do with it, but there are other factors.

If you hit a cueball with English (or side) with a very light shaft of titanium, do you think it would deflect , or squirt, the cue ball or not? If the shaft cannot bend out of the way during contact, then there would be a much higher deflection.

Therefore, NO, snooker shafts are not low deflection shafts at all. They would be much worse, however, if they were thicker.

I don't think the shaft bends, it just gets knocked to the side. So I do think a very low end-mass titanium cue would be low deflection. But I'm not sure.

I also don't think the snooker guys use much sidespin on long shots, where deflection is really important. It's hard enough just making the shot - when they make a long straight in shot, the audience claps.

I hope to be educated on both these subjects.

Patrick Johnson
06-19-2009, 06:13 AM
Snooker cue shafts are made of ash which is a much more rigid wood, so they wouldn't really be low deflection at all.

The rigidity of the shaft doesn't seem to matter. Tests have shown that flexible shafts can be high-squirt and rigid shafts can be low-squirt. The only thing that seems to matter much is end mass.

pj
chgo

Patrick Johnson
06-19-2009, 06:14 AM
...shouldn't snooker shafts be low deflection? Or does the brass ferrule make it heavier?

Yes and yes.

Snooker shafts are lower deflection, but not as low as they could be without the brass ferrules.

pj
chgo

McChen
06-19-2009, 08:09 AM
most of the english snooker cues have brass ferrules, but i've seen a lot of canadian one made with phenolic ferrules. that would cut down on the deflection some

Cornerman
06-19-2009, 08:17 AM
It is a well established fact that deflection depends on the mass of the end of the shaft on any given cue.

Snooker shafts have smaller diameters which would logically mean that the end mass is lighter.

So the question is shouldn't snooker shafts be low deflection? Or does the brass ferrule make it heavier? Ditto to what PJ said.

If the shaft is low deflection what are the drawbacks for hitting pool balls with snooker cues?No draw back, IMO.

Fred

Clark_the_Shark
06-19-2009, 08:25 AM
Yes, but the balls are also smaller (lighter?) too. It's not just endmass, it's endmass vs. the object you are hitting. So who knows, maybe it just evens out?

tjlmbklr
06-19-2009, 08:36 AM
It is a well established fact that deflection depends on the mass of the end of the shaft on any given cue.

Snooker shafts have smaller diameters which would logically mean that the end mass is lighter.

So the question is shouldn't snooker shafts be low deflection? Or does the brass ferrule make it heavier?

If the shaft is low deflection what are the drawbacks for hitting pool balls with snooker cues?

Without reading all the responses this may have been answered already. The cues are lower deflection....for a 2-1/4" ball (pool) but they are designed for 2-1/8" ball (Snooker) so the ratio of the smaller shaft is made for the smaller balls.

As I read in one of the replies yes they are usually made stiffer too which may result in more deflection then say a standard pool playing cue but they are only made to move a lighter ball so it works out good.

So the final answer is yes for pool they may have less deflection but the amount might not make it worth it to use a Snooker cue for pool although I know Steve Davis used to or maybe still does. But he is also a Snooker player and it prolly felt more comfortable to him.

Hope this helps.

I am not a Scientist, but I did stay at a Holiday inn Express last night! :thumbup:

hjs032570
06-19-2009, 09:56 AM
The rigidity of the shaft doesn't seem to matter. Tests have shown that flexible shafts can be high-squirt and rigid shafts can be low-squirt. The only thing that seems to matter much is end mass.

pj
chgo


I saw Patrick Johnson's tests on Youtube. He empirically showed deflection is really affected by end mass. I always felt that the shaft taper would have an effect but his tests blew that theory out of water. Props to you Patrick Johnson.

mnorwood
06-19-2009, 10:45 AM
Thanks for the responses so far. I have really been leaning towards shooting with a John Parris for snooker and pool.

Fatboy
06-19-2009, 10:50 AM
Without reading all the responses this may have been answered already. The cues are lower deflection....for a 2-1/4" ball (pool) but they are designed for 2-1/8" ball (Snooker) so the ratio of the smaller shaft is made for the smaller balls.

As I read in one of the replies yes they are usually made stiffer too which may result in more deflection then say a standard pool playing cue but they are only made to move a lighter ball so it works out good.

So the final answer is yes for pool they may have less deflection but the amount might not make it worth it to use a Snooker cue for pool although I know Steve Davis used to or maybe still does. But he is also a Snooker player and it prolly felt more comfortable to him.

Hope this helps.

I am not a Scientist, but I did stay at a Holiday inn Express last night! :thumbup:


proper snooker balls are 2 1/16"

ShootingArts
06-19-2009, 01:08 PM
Thanks for the responses so far. I have really been leaning towards shooting with a John Parris for snooker and pool.

Not sure of her current status but Karen Corr has shot pool with her snooker cue at a very high level and has went back to her snooker cue again according to fairly recent reports.

I shot pool with a 12oz snooker cue made by Brunswick for several years. This was a cheap house cue with a plastic ferule. I changed the tip to a milk dud, no other changes. This was indeed a low deflection cue and a monster to get used to playing with, both because of the cue ball taking new paths and because of having to use entirely different force hitting the cue ball than the cue I had been playing with that weighed half again as much. Once I mastered this cue I had a level of cue ball control that was nothing short of ridiculous however. Tough to say how much was due to the weight of the cue and how much was deflection changes, all I can say is the overall result was little short of miraculous.

Note the new OB-2 shaft. I have only secondhand reports but the tip is small and the taper is much like a snooker cue's from what I have been told. I think one of the 314's is similar with a smallish tip and faster taper than the typical "pro taper" shaft. The cue ball doesn't know if you are using a snooker cue or a pool cue with the shaft cut much like a snooker cues.

I don't know of any reason that your snooker cue can't work on a pool table particularly with the fast cloth used on today's tables. There may be a fairly tough transition period if you are using a pro taper shaft now. Some pro taper shafts have very undesirable flex characteristics in my opinion. The snooker shaft taper has much more desirable flex characteristics, again in my opinion. Regardless, there is a huge change when going between the two and adjustment takes awhile.

An edit to make clear that "pro taper" is loosely applied to many slightly different tapers. Some have no flex issues, some do. The ones without flex issues will still flex differently than a snooker shaft and require some adjustment but it won't be the huge adjustment required once you have learned to shoot with a shaft that has most of the flex well back from the tip on the shaft.

Hu

Rich93
06-19-2009, 01:35 PM
I saw Patrick Johnson's tests on Youtube. He empirically showed deflection is really affected by end mass. I always felt that the shaft taper would have an effect but his tests blew that theory out of water. Props to you Patrick Johnson.

Where are these youtubes? I'd love to see them, especially if accompanied by the pj wit.

Jal
06-19-2009, 01:40 PM
The rigidity of the shaft doesn't seem to matter. Tests have shown that flexible shafts can be high-squirt and rigid shafts can be low-squirt. The only thing that seems to matter much is end mass.

pj
chgoPatrick,

As a practical matter, I guess the data supports your conclusions. (Dr. Dave did some tests with notched "Beaver" shafts which even seem to indicate slightly more squirt when operated in the most flexible orientation?) But strictly speaking, the amount of endmass that gets shoved aside does depend on the rigidity of the shaft. Rigidity is an integral part of effective endmass. You have a bunch of little masses connected to each other, and they each get set into motion. How much sideways velocity each one picks up is characterized by the shape of the shaft as it bends. Equations exist for a statically loaded cylindrical cantilever, and these can be modified without too much trouble for a conical cantilever. I've also seen them for a vibrating cylindrical cantilever. But while they may exist, I've yet to come across any for a dynamically loaded cantilever, which is what you have during impact. So it isn't all that easy to put numbers on it.

I'm wondering if your experience of rigid vs flexible comes primarily from comparisons of tapered vs cylindrical shafts? Tapered shafts may give the impression of being more rigid, because they are, overall. But in the last few inches where it really counts, and where they become thinner than "pro tapers", they should be more flexible. What to make out of all of this...

Jim

Siz
06-19-2009, 02:31 PM
Patrick,

But in the last few inches where it really counts, and where they become thinner than "pro tapers", they should be more flexible.

Jim

All very interesting. How far from the tip do mass variations become insignificant to a player experiencing squirt? And how quickly does the effect fall away with distance?

BTW, to muddy the waters even further in the snooker cue / pool cue comparison, snooker ferules are usually dense (brass) but the effect will be mitigated by the fact that they are also much shorter than pool ferules.

Bob Jewett
06-19-2009, 02:35 PM
Ditto to what PJ said.

No draw back, IMO [on using a snooker cue for pool].

Fred
I agree with Fred. However, you will get contrary views from some snooker players. Many of the top snooker players who sometimes shoot pool get special pool shafts. Some feel that the larger ball will damage the smaller tip.

The density of the brass ferrule seems to be less of a problem because the ferrule is usually quite short and is hollow.

hjs032570
06-19-2009, 03:12 PM
Where are these youtubes? I'd love to see them, especially if accompanied by the pj wit.


I have to find the thread, he had posted them when he started the thread.

tjlmbklr
06-19-2009, 03:27 PM
proper snooker balls are 2 1/16"

Wouldn't doubt that since I was only told they were 2-1/8" but they always seem smaller then 1/8" than a standard pool ball.

Jal
06-19-2009, 03:45 PM
All very interesting. How far from the tip do mass variations become insignificant to a player experiencing squirt? And how quickly does the effect fall away with distance?Mike Page did experiments several years ago and found that mass added beyond about 6" from the tip had no noticeable effect on the amount of squirt. Steve "I'm blocking on his last name" of Platinum Billiards measured the effects of a certain amount of mass added at specific distances from the tip. He reported the results to the RSB group (rec.sports.billiards) some time ago too. More recently, Dr. Dave did the same sort of test(s) for his Feb., 2008 article in "Billiards Digest." (See Diagram 4 on page 4.)

http://billiards.colostate.edu/bd_articles/2008/feb08.pdf

Several more articles on squirt (amongst others) are available on the same web-page:

http://billiards.colostate.edu/bd_articles/index.html

BTW, to muddy the waters even further in the snooker cue / pool cue comparison, snooker ferules are usually dense (brass) but the effect will be mitigated by the fact that they are also much shorter than pool ferules.If you use the empirical data from above and figure in the different mass densities of brass and other ferrule materials, as well as the relevant dimensions, you might be able to come up with a comparative estimate. Sorry, haven't the time myself right now. :)

Jim

Patrick Johnson
06-19-2009, 05:07 PM
I saw Patrick Johnson's tests on Youtube. He empirically showed deflection is really affected by end mass. I always felt that the shaft taper would have an effect but his tests blew that theory out of water. Props to you Patrick Johnson.

I've never posted to youtube, but props to that other Patrick Johnson from me too. (Sure you don't mean my buddy Mike Page?)

I'm only reporting what I've heard from others who have tested over the years. As JAL says, rigidity theoretically should have some effect on squirt - maybe the range of rigidity among pool cues is just too slight to matter.

pj
chgo

McChen
06-19-2009, 05:18 PM
Wouldn't doubt that since I was only told they were 2-1/8" but they always seem smaller then 1/8" than a standard pool ball.

american snooker balls are typically 2 1/8" but the english ones are 2 1/16"

Patrick Johnson
06-19-2009, 05:58 PM
I agree with Fred. However, you will get contrary views from some snooker players. Many of the top snooker players who sometimes shoot pool get special pool shafts. Some feel that the larger ball will damage the smaller tip.

As I tell everybody who will listen, my pool shafts have 10mm tips (maybe smaller). I never break with them, but even so I've replaced a few ferrules in the three years I've had them. I'm pretty sure this is because the ferrules are made like the ones on thicker tips: hollow sleeves that slip over a round tenon at the end of the shaft. My shafts are thin and hollow, so the ferrule walls and the tenon walls have to be thinner.

As a matter of fact I'm having one replaced right now, but I'm finally having the short tenon cut off and a thin solid disc glued on (which is the way I designed it in the first place). When my next one goes I may try just a fiber tip pad with no ferrule. I believe Bob Jewett plays (at least sometimes) with a tip glued directly to his shaft wood.

pj
chgo

Fatboy
06-19-2009, 06:45 PM
american snooker balls are typically 2 1/8" but the english ones are 2 1/16"


its makes a huge difference from 2 1/8" down to 2 1/16". I can use a pool cue with a 12mm shaft on 2 1/8" balls, not possible with the smaller ones


I have 2 1/16" balls on my table at home, If I use my cue which has a 12.75mm shaft I cant draw the ball much or get any side spin either-some but not much, force follow is there, since I'm used to a pool cue I pot(make) balls real easly compaired to my snooker cue.


With the snooker cue-(its ash with a 9.5mm brass ferreul) I get alot of side spin, draw, follow, but my potting is bad because i'm not used to the cue, its a world of difference between the 2 cues.


I wouldnt hit pool balls with my snooker cue only because it would smash the tip flat, when my tip is worn out I'm going to play pool with it before I put a new tip on, I just havent had the cue long enough to go do that, I dont think a snooker cue will be good for pool.


2 different games- 2 different tools(cues) are required, A different shaft is a half-assed solution even using the 2 1/8" balls it might work but the proper cue is the solution.


I also dont think its possible to play both games in top form at the same time, its ALOT different. proper English snooker on nap cloth, vs, American pool. the stroke, stance, everything is very different.

mnorwood
06-19-2009, 07:57 PM
its makes a huge difference from 2 1/8" down to 2 1/16". I can use a pool cue with a 12mm shaft on 2 1/8" balls, not possible with the smaller ones


I have 2 1/16" balls on my table at home, If I use my cue which has a 12.75mm shaft I cant draw the ball much or get any side spin either-some but not much, force follow is there, since I'm used to a pool cue I pot(make) balls real easly compaired to my snooker cue.


With the snooker cue-(its ash with a 9.5mm brass ferreul) I get alot of side spin, draw, follow, but my potting is bad because i'm not used to the cue, its a world of difference between the 2 cues.


I wouldnt hit pool balls with my snooker cue only because it would smash the tip flat, when my tip is worn out I'm going to play pool with it before I put a new tip on, I just havent had the cue long enough to go do that, I dont think a snooker cue will be good for pool.


2 different games- 2 different tools(cues) are required, A different shaft is a half-assed solution even using the 2 1/8" balls it might work but the proper cue is the solution.


I also dont think its possible to play both games in top form at the same time, its ALOT different. proper English snooker on nap cloth, vs, American pool. the stroke, stance, everything is very different.

What tip are you using? I have a buddy that shoots pool with an elkmaster tip and he has never complained about it getting smashed. You can by hard, rigid snooker tips also.

Patrick Johnson
06-20-2009, 12:49 AM
Fatboy:
its makes a huge difference from 2 1/8" down to 2 1/16".

I think it's actually 2 1/6" down to 2 1/15", but who's counting?

Here's a comparison of billiard ball sizes and weights (and a Wikipedia article (http://en.wikipedia.org/wiki/Billiard_ball) about them):

100134

Compared to an American pool ball:

A carom ball is 25% heavier.
A British pool ball is 6% lighter.
An American snooker ball is 8% lighter.
A British snooker ball is 22% lighter.

A Russian pool ball is 68% heavier! :eek:

pj
chgo

Edit: British balls measured in mm, converted to inches (rounded to nearest 1/16); American balls measured in inches, converted to mm (rounded to nearest .1 mm).

Siz
06-20-2009, 01:17 AM
As I tell everybody who will listen, my pool shafts have 10mm tips (maybe smaller)...

Absolutely. I think that the main reason why some top snooker players are unwilling to use their snooker cue when playing pool is a fear of damaging it that can approach paranoia. It is usual for snooker players to have only one cue and for them to use if for decades - perhaps all their playing career. Not a good idea IMHO, since it tends to generate a state of dependency (real or imagined) on a single cue.

BTW I think that the table included in a later post has a slight inaccuracy: Outside the US, standard snooker (and English billiard) balls are 2 1/16" not 2 1/15". But as you say - who's counting?

Cornerman
06-20-2009, 02:09 AM
american snooker balls are typically 2 1/8" but the english ones are 2 1/16"

This is my experience also. In fact, my "home pool rooom" had a 12' snooker table from Canada, but had 2 1/8" balls and small pockets. It must be some running joke to setup 12' snooker tables in America with horrendously tight pockets. So, we all thought that the snooker players must be just so tremendous since none of us could have fun on the table for too long while we watched on TV the snooker champions making it looks so easy.

Then I went to Europe. Same size tables. Slightly bigger pockets. Slightly smaller balls. I'm not saying it's easy, but it's a hell of a lot easier than what we were doing. My guess is that over 90% of all Americans whose only experience in snooker is on tricked out 12' tables or on American Snooker tables have no idea the fun they could actually have on proper equipment.

Fred

McChen
06-20-2009, 03:06 AM
I think it's actually 2 1/6" down to 2 1/15", but who's counting?

Here's a comparison of billiard ball sizes and weights (and a Wikipedia article (http://en.wikipedia.org/wiki/Billiard_ball) about them):

100134

Compared to an American pool ball:

A carom ball is 26% heavier.
A British pool ball is 5% lighter.
An American snooker ball is 10% lighter.
A British snooker ball is 22% lighter.

A Russian pool ball is 70% heavier! :eek:

pj
chgo

there's a bunch of mistakes on that table. english snooker balls are definitely 2 1/16". and english pool balls are 2", even smaller than snooker balls. the cue ball is a different size most of the time, 1 7/8"

TX Poolnut
06-20-2009, 08:09 AM
Interesting thread.

ShootingArts
06-20-2009, 08:21 AM
This is my experience also. In fact, my "home pool rooom" had a 12' snooker table from Canada, but had 2 1/8" balls and small pockets. It must be some running joke to setup 12' snooker tables in America with horrendously tight pockets. So, we all thought that the snooker players must be just so tremendous since none of us could have fun on the table for too long while we watched on TV the snooker champions making it looks so easy.

Then I went to Europe. Same size tables. Slightly bigger pockets. Slightly smaller balls. I'm not saying it's easy, but it's a hell of a lot easier than what we were doing. My guess is that over 90% of all Americans whose only experience in snooker is on tricked out 12' tables or on American Snooker tables have no idea the fun they could actually have on proper equipment.

Fred


Fred,

When I see the overheads of the Championship snooker tables and a close-up of a Riley Championship pocket I am amazed at how soft the pockets are compared to the monsters that I spent two or three hours a day on for a few years. Interestingly I was talking to a friend from the Philippines and started talking about the pockets on the snooker tables I played on. He got all excited, said that was exactly the kind of table he learned on.

I don't know if the old antiques were made that way or someone modified them somewhere over the years but the toughest thing about the tables was a very small pocket radius cut very deep in the pocket. The wider radius further out makes shots far easier. Even so, the toughest thing about the monsters was changing my mindset about what was an acceptable shot. Once I learned what the pockets would accept snooker became a far easier game.

I find it funny that people don't recognize that played right the vast majority of the game is played in a 3x6 area and then there is a set pattern of balls just like a drill that finishes every game. Snooker is a little harder than pool but not nearly as much harder as people that try it once or twice imagine.

Hu

dr_dave
06-20-2009, 02:44 PM
Where are these youtubes? I'd love to see them, especially if accompanied by the pj wit.Here are some videos dealing with squirt:

NV B.1 - Mike Page's squirt and swerve video (http://billiards.colostate.edu/normal_videos/new/NVB-1.htm)
NV B.32 - Squirt and the effects of endmass (http://billiards.colostate.edu/normal_videos/new/NVB-32.htm)
HSV B.47 - effect of shaft endmass and squirt on miscue limit (http://billiards.colostate.edu/high_speed_videos/new/HSVB-47.htm)

I also have many links to additional article and video resources dealing with squirt here:
http://billiards.colostate.edu/threads/squirt.html

Regards,
Dave

dr_dave
06-20-2009, 02:49 PM
Sorry for my late reply. I was out of town this past week.

It is a well established fact that deflection depends on the mass of the end of the shaft on any given cue.

Snooker shafts have smaller diameters which would logically mean that the end mass is lighter.

So the question is shouldn't snooker shafts be low deflection? Or does the brass ferrule make it heavier?PJ, Fred, Bob, and Jal have answered this already. A smaller shaft and smaller (and lighter) ferrule result in less endmass and less squirt.

If the shaft is low deflection what are the drawbacks for hitting pool balls with snooker cues?Some people might not like the "feel" or "hit" of a snooker cue. Also, some people might not like a low-squirt cue if they are more accustomed to a squirtier cue. For more info, see:

http://billiards.colostate.edu/threads/cue.html#low_squirt

Regards,
Dave

PS: FYI, I have a lot of info and links to useful resources about squirt here:
http://billiards.colostate.edu/threads/squirt.html

Patrick Johnson
06-20-2009, 05:46 PM
there's a bunch of mistakes on that table.

You mention only two (is that "a bunch"?), and you're mistaken about at least one of them.

english snooker balls are definitely 2 1/16".

According to the International Billiards and Snooker Federation (http://www.ibsf.info/rules-snooker.shtml):

"The balls ... shall each have a diameter of 52.5mm with a tolerance of +/- 0.05mm"

If you do the math you'll find that's 2 1/15" (actually slightly more), not 2 1/16". I assume people say 2 1/16" because inches are commonly divided into 16ths and 1/15 is very close to 1/16.

english pool balls are 2", even smaller than snooker balls. the cue ball is a different size most of the time, 1 7/8"

The IBSF says "English billiard balls" are the same size as snooker balls (http://www.ibsf.info/rules-billiards.shtml). Are you talking about the same balls?

pj
chgo

McChen
06-20-2009, 08:20 PM
i always heard the balls referred to as 2 1/16", but i can buy that that's a rounding error

english billiard use the same balls and table as snooker, so they should be the same size. the table said english pool balls, which i took to mean english 8-ball (reds & yellows).

mnorwood
06-20-2009, 11:05 PM
Sorry for my late reply. I was out of town this past week.

PJ, Fred, Bob, and Jal have answered this already. A smaller shaft and smaller (and lighter) ferrule result in less endmass and less squirt.

Some people might not like the "feel" or "hit" of a snooker cue. Also, some people might not like a low-squirt cue if they are more accustomed to a squirtier cue. For more info, see:

http://billiards.colostate.edu/threads/cue.html#low_squirt

Regards,
Dave

PS: FYI, I have a lot of info and links to useful resources about squirt here:
http://billiards.colostate.edu/threads/squirt.html

Thanks I always enjoy your input.:smile:

Patrick Johnson
06-21-2009, 10:25 AM
i always heard the balls referred to as 2 1/16", but i can buy that that's a rounding error

english billiard use the same balls and table as snooker, so they should be the same size. the table said english pool balls, which i took to mean english 8-ball (reds & yellows).

I took the names and sizes from the Wikipedia article, which might not be 100% accurate. If anybody knows of a better source, I'd be happy to update the chart.

pj
chgo