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X Breaker
04-11-2005, 12:45 AM
Does anyone know where to get a radar gun to measure break speed? I am looking for one with at least one decimal place.

Thank you very much.

Richard

mjantti
04-11-2005, 01:04 AM
Try law enforcement :p

I wonder what kind of setup is required for measuring break speeds with a speed gun. As the method for measuring is based on Doppler effect, you'd need to stand in front of the breaker but then you get signals from the moving cue and breakers arms etc. as well. How do you/they separate the cueball speed from all the excess background "noise" ?

I'm currently working on my Master's thesis work on a relating issue...

X Breaker
04-11-2005, 01:24 AM
Try law enforcement :p

I wonder what kind of setup is required for measuring break speeds with a speed gun. As the method for measuring is based on Doppler effect, you'd need to stand in front of the breaker but then you get signals from the moving cue and breakers arms etc. as well. How do you/they separate the cueball speed from all the excess background "noise" ?

I'm currently working on my Master's thesis work on a relating issue...

Very interesting input.

Since radar guns are also used to measure the speed of bat movement, club head speed...etc in various sports, I am pretty sure it can be done.

Can the radar gun be focused on the speed of the cue ball alone?

Richard

drivermaker
04-11-2005, 04:42 AM
Very interesting input.

Since radar guns are also used to measure the speed of bat movement, club head speed...etc in various sports, I am pretty sure it can be done.

Can the radar gun be focused on the speed of the cue ball alone?

Richard


For such a short distance between the CB and the rack, that's where the real problem lies. Additionally, it also has to do with the relatively low speed of the CB (under 40mph and in most cases under 30). Regular radar guns are programmed and calibrated to register speeds higher than that.

For golf, you can get radar guns that register CLUB HEAD speed and also the initial velocity of the golf ball itself in MPH. Both speeds are quite different from each other. I really don't know what the hell the speed guns that are being used for pool are actually picking up to get their measurements in mph. and if they're properly programmed for the lower speed of the CB itself. I think they're using the "JUG" brand.

vapoolplayer
04-11-2005, 05:30 AM
try contacting SARDO on this matter. carmine sardo was the one using the radar gun at the US Open this past year. he can probably shed some light on this.

VAP

td873
04-11-2005, 06:43 AM
Does anyone know where to get a radar gun to measure break speed? I am looking for one with at least one decimal place.

Thank you very much.

Richard
I have one that measures whole numbers only, and it works great for breaks. If you want to know more let me know. It Costs between $100 and $200 depending on the features you want. If you want to measure to the tenths place, you are looking at around $1000 bucks...

Let me know if you want more info.

FYI, the fastest break I've timed was Frankie Hernandez at 26 MPH...

-td

ceebee
04-11-2005, 06:46 AM
[QUOTE=nipponbilliards]Does anyone know where to get a radar gun to measure break speed? I am looking for one with at least one decimal place.

Thank you very much. ENDQUOTE

Radar Guns will have a problem under Fluorescent Lights

Mr. Wilson
04-11-2005, 06:59 AM
I'm also a target shooting enthusiast.

Why couldn't a chronograph be modified to capture a cueball?
They can measure from just a few feet per second up to 7000 FPS.

Dave

drivermaker
04-11-2005, 07:46 AM
I have one that measures whole numbers only, and it works great for breaks. If you want to know more let me know. It Costs between $100 and $200 depending on the features you want. If you want to measure to the tenths place, you are looking at around $1000 bucks...

Let me know if you want more info.

FYI, the fastest break I've timed was Frankie Hernandez at 26 MPH...

-td


Only 26 mph...Frankie is NOT a powder puff hitter. Based on what you've measured with other players and seen of the women, what do you think the top women would come out at compared to Frankie with YOUR device?
(This is what I'm getting at...the differences and discrepencies in a variety of guns)

Where do you place the unit when measuring break speed and what is the lowest that you've seen it register? Who is the manufacturer and what model is it? What other applications can it be used for...such as golf swing speed, bat speed, auto racing, pitched baseball? If you don't want to post, please PM me.

drivermaker
04-11-2005, 07:50 AM
I'm also a target shooting enthusiast.

Why couldn't a chronograph be modified to capture a cueball?
They can measure from just a few feet per second up to 7000 FPS.

Dave


A FEW FEET per second? And what do you think the elapsed time would be from tip contact on the CB to impact on the rack...what part of a second? Would the human reaction time be quick enough to get it?

drivermaker
04-11-2005, 08:04 AM
Try law enforcement :p


Their radar guns are for speeders...not someone lollygagging at 25 miles an hour on a 4 lane expressway that's whacked to the limit on weed. :eek: :D

Rackin_Zack
04-11-2005, 09:02 AM
It's not quick, but I would think the best way to accurately measure break speed would be to calculate it using the time the cueball takes to get to the rack and the distance traveled. It's just plug and chug from there. I guess the hardest part would be measuring the time precisely, but perhaps high speed video could be used or something to that effect.

Since 1 mph is ~ 1.467 fps so a 30 mph (44 fps) break is only going to take about .11 seconds (assuming a distance of about 5 feet). Perhaps lasers could be used to measure the time like in autocrossing (ball breaks the plane of two lasers with a known distance between them). Just thought I'd throw out some ideas...lol.

td873
04-11-2005, 09:09 AM
Only 26 mph...Frankie is NOT a powder puff hitter. Based on what you've measured with other players and seen of the women, what do you think the top women would come out at compared to Frankie with YOUR device?
(This is what I'm getting at...the differences and discrepencies in a variety of guns)

Where do you place the unit when measuring break speed and what is the lowest that you've seen it register? Who is the manufacturer and what model is it? What other applications can it be used for...such as golf swing speed, bat speed, auto racing, pitched baseball? If you don't want to post, please PM me.

I have some statistical info at home, but from what I remember: the average male pro breaks around 24.5 MPH, and the average female pro breaks around 19.6. Taking into account the inherent erro in off-angle measurements, I would estimate that Frankie's break was actually 5% faster than the gun measured. That 26 is actually pretty good, all things considered.

FWIW, I don't think that the gun itself makes a difference, and in particular, I don't thing my device would fair better or worse against a police radar gun, or a military one. As the techonology is fairly straightforward, any radar gun will be accurate to within a MPH or maybe two, but this is less relevant than the angle you measure the from. I.e., the Cosine Effect results in two measurements that you have to account for when measuring breaks: horizontal AND vertical. Without giving the math, a 15° angle results in about a 3.5% margin of error, and a 30° angle results in about a 13% margin of error. [This is the case with any radar gun.] I use 5% since I measure from about 15° to the side and around a foot above the table as well.

When measuring speed with a radar gun, you should be as close to in front or behind the moving object as possible (on the same planes as the thing you are measuring). However, for breaks, if you stand directly behind or in front, there is a tendency for the machine to register the stick, the shooter, or even the object balls after impact. That's why I measure from 15° to the side... I aim right at the center spot and usually get an accurate reading.

To calculate the speed taking the Cosine Effect into account (at 15°), take the speed, move the decimal in one place (divide by 10) and half the number. Add this to what you started with, and that would be the adjusted speed. (i.e., if the machine shows 18, 18/10 = 1.8 and half of that is .9, so the speed would be 18.9 MPH).

If a player breaks from the side rail, and you measure from the center spot, you are at about 30°. If you are a foot or so above the table, you'll have another 2% error, so that's about 15% off. Take the reading, move the decimal, add that number and half that number to what the machine had. (i.e., if the machine shows 18, take 18 + 1.8 + .9 = 20.7).

*I always tell the shooter what the machine says without the Cosine modification...*

The one I use is a Bushnell Speedster. It measures from 10 MPH to around 200 MPH. It is designed to measure baseballs, but can be used for cars etc. For clubhead speed or baseball bat speed, you really need a chronograph as mentioned above.

If you have any other q's, let me know.

-td

td873
04-11-2005, 09:11 AM
Would the human reaction time be quick enough to get it?

This type of chronograph uses doppler radar to measure the velocity of moving objects. [Radar or light chronography]. It is not the "stopwatch" variety.

-td

Johnny "V"
04-11-2005, 09:19 AM
This is what you need... There are also schematics on the internet on how to build your own.

http://www.vernier.com/probes/probes.html?vpg-btd&template=standard.html

Figure out how to make one that fits under the rails on either side of the table and you may get 20 or so people to buy them.

JV

BTW I get a free one for coming up with the idea... :)

jaz
04-11-2005, 09:19 AM
I was thinking about this and I think a simple device could be constructed to ensure consistency and accuracy for measurement. This is based on the same theory (I think) that's used for FPS measurements in shooting (speed measured over a limited distance)

Half-assed diagram for thoughts....

Bruce S. de Lis
04-11-2005, 09:35 AM
I was thinking about this and I think a simple device could be constructed to ensure consistency and accuracy for measurement. This is based on the same theory (I think) that's used for FPS measurements in shooting (speed measured over a limited distance)

Half-assed diagram for thoughts....

Looks like a Pool Ball Speed Trap, and I think it would work.... ;)

Rackin_Zack
04-11-2005, 09:42 AM
It looks like a few of us posted the same exact idea, for the most part, at pretty much the same time...lol.

Fred Agnir
04-11-2005, 09:53 AM
This is what you need... There are also schematics on the internet on how to build your own.

http://www.vernier.com/probes/probes.html?vpg-btd&template=standard.html

Figure out how to make one that fits under the rails on either side of the table and you may get 20 or so people to buy them.

JV

BTW I get a free one for coming up with the idea... :)

This is basically the best idea, IMO. The CueTech Pool SChool uses something very similar. As you may remember John, I'm in the automation field. I can build these things in a heartbeat, but it's simply not cost effective.

Fred

Fred Agnir
04-11-2005, 09:57 AM
It looks like a few of us posted the same exact idea, for the most part, at pretty much the same time...lol.

Great minds and all that...

But, to answer the underlying Drivermaker question, the speeds measured by the Cuetech Pool School devise (start/stop non-contact photoswitches) were well within the same expected range as the radar gun measurements. That is, if there was a difference, it'd be difficult to convince anyone that there was a significant difference.

And as stated before, the actual number isn't so important if everyone (men vs. women) gets measured by the same equipment. Long and short: Sarah and Tiffany have been proven by measurement that they break harder than the vast majority of men.

Fred

Nostroke
04-11-2005, 10:06 AM
Does anyone know where to get a radar gun to measure break speed? I am looking for one with at least one decimal place.

Thank you very much.

Richard

Guns for sports here
http://www.opticsplanet.net/busspeedrads.html

Johnny "V"
04-11-2005, 10:09 AM
This is basically the best idea, IMO. The CueTech Pool SChool uses something very similar. As you may remember John, I'm in the automation field. I can build these things in a heartbeat, but it's simply not cost effective.

Fred
They sell the device for 43 bucks including software. I am assuming you need the daisy chain for it to register speed. If you could break apart a couple of those laser pointers and mount them in a triangular piece that fit under the rail on one side of the table and rip apart a couple of these units (which I figure is a photocell) and mount it in another triangular piece you would be in like flint... Really I think it could be done for less than a hundred bucks... I would consider trying it but I am in the process of putting a new roof on my house so I don't have any time right now.

JV

drivermaker
04-11-2005, 10:59 AM
I have some statistical info at home, but from what I remember: the average male pro breaks around 24.5 MPH, and the average female pro breaks around 19.6. Taking into account the inherent erro in off-angle measurements, I would estimate that Frankie's break was actually 5% faster than the gun measured. That 26 is actually pretty good, all things considered.

FWIW, I don't think that the gun itself makes a difference, and in particular, I don't thing my device would fair better or worse against a police radar gun, or a military one. As the techonology is fairly straightforward, any radar gun will be accurate to within a MPH or maybe two, but this is less relevant than the angle you measure the from. I.e., the Cosine Effect results in two measurements that you have to account for when measuring breaks: horizontal AND vertical. Without giving the math, a 15° angle results in about a 3.5% margin of error, and a 30° angle results in about a 13% margin of error. [This is the case with any radar gun.] I use 5% since I measure from about 15° to the side and around a foot above the table as well.

When measuring speed with a radar gun, you should be as close to in front or behind the moving object as possible (on the same planes as the thing you are measuring). However, for breaks, if you stand directly behind or in front, there is a tendency for the machine to register the stick, the shooter, or even the object balls after impact. That's why I measure from 15° to the side... I aim right at the center spot and usually get an accurate reading.

To calculate the speed taking the Cosine Effect into account (at 15°), take the speed, move the decimal in one place (divide by 10) and half the number. Add this to what you started with, and that would be the adjusted speed. (i.e., if the machine shows 18, 18/10 = 1.8 and half of that is .9, so the speed would be 18.9 MPH).

If a player breaks from the side rail, and you measure from the center spot, you are at about 30°. If you are a foot or so above the table, you'll have another 2% error, so that's about 15% off. Take the reading, move the decimal, add that number and half that number to what the machine had. (i.e., if the machine shows 18, take 18 + 1.8 + .9 = 20.7).

*I always tell the shooter what the machine says without the Cosine modification...*

The one I use is a Bushnell Speedster. It measures from 10 MPH to around 200 MPH. It is designed to measure baseballs, but can be used for cars etc. For clubhead speed or baseball bat speed, you really need a chronograph as mentioned above.

If you have any other q's, let me know.

-td


td....I just had a phone conversation with the high-tech buddha at the Bushnell Corporation and he said that the Speedster or Velocity model would work but, as you said, whether it's Bushnell, Jugs, or any other model or manufacturer, a calculation has to be done to get an accurate reading based on the angle in which the gun is being held. (as much in height above the oncoming CB as well as side) since it's calibrated at 0 degrees. Normally, the readout on the unit will be LESS than actual but the percentage based on the angle needs to be factored in to get a true reading.

Have you ever attempted to get a reading with NO balls racked and only the CB being smashed into the end rail with the unit at table level, (actually only a couple of degrees higher while resting on a tripod or end rail)?

He thought the new Velocity model might be better because it's more durable than the Speedster, although almost twice the size.

X Breaker
04-11-2005, 11:36 AM
Thank you very much everyone.

Let me see if I have gotten this down correctly.

1. If the gun is placed in front of, or right behind of the breaker, and is held as level as possible, then it will produce the most accurate result.

2. If the gun is elevated at a slight angle, it will read less than the actual speed.

3. Nevertheless, if I have the gun on a tripod and record the break from the same elevated angle and distance for all the players in my sample, I can still have a resonably accurate comparison of their break speeds.

I have a few more questions:

1. Can I calibrate my gun so it could actually read a higher speed than the actual speed?

2. Are you focusing on the cueball when it leaves the cue, or the cue ball when it strikes the 1 ball, when you obtain your reading?

3. Should I move the radar gun depending on where the breakers break from?

If I focus on the moment when the ball leaves the cue, I think I may have to move my gun around and it could be difficult to keep the same angle and distance for all the players that way...

If I focus on the cueball at the moment when it strikes the pack, will the reading be accurate if the cue ball jumps up, when it strikes the 1 ball?

Thomas, does your gun come with a tripod, it cannot read to 1 decimal place, can it?

I found this company which rents out radar guns and related equipments, http://www.stalkerradar.com/rental.shtml, have any of you heard of them?

Obviously, lots of you have been thinking about this a lot and is quite knowledgable on the subject. All your suggestions/comment are very much appreciated.

I am thinking about using it in an application similar to that of the Sardo's in the US open and Vegas, I need something reliable, durable, and consistent.

I will be looking forward to your reply. Once again, thank you very much.

Richard

X Breaker
04-11-2005, 11:45 AM
One more question...and this is very unlikely to be my last one... ;)

When you folks enter the breaking contest, will you apprecaite to see your break speed on a big electronic display board, much like the kind used by the police to display car speeds on the highway?

Has anyone worked with such type of equipment before?

Richard

td873
04-11-2005, 11:54 AM
Normally, the readout on the unit will be LESS than actual but the percentage based on the angle needs to be factored in to get a true reading.
That makes sense. As I mentioned above, with a lower reading on the machine, I add back some of the calculated error to get an approximated true reading (i.e, if the machine reads 20, with 15% error, I add back on 15% of 20 (3MPH), rather than the actual 20/.85 = 3.52MPH. Just makes math easier at the pool hall)

Have you ever attempted to get a reading with NO balls racked and only the CB being smashed into the end rail with the unit at table level, (actually only a couple of degrees higher while resting on a tripod or end rail)?
Yes (but not on a tripod). I really couldn't tell if this made a difference, since a speed was still registered. It wasn't any easier or harder to get a reading without the rack there (the rack being there has no effect on the machine catching the cue ball if you are aiming at the right spot). Also, being a couple inches above the table doesn't really affect the overall reading. The cue ball travels 4 diamonds (about 40") down the table. If you are 2 inches above the playing surface, you are only adding 0.12% error to the calculation. Even a foot above only causes 4.2% error... Two feet above, however, creates another 14.25% error.

-td

DaveK
04-11-2005, 11:58 AM
They sell the device for 43 bucks including software. I am assuming you need the daisy chain for it to register speed. If you could break apart a couple of those laser pointers and mount them in a triangular piece that fit under the rail on one side of the table and rip apart a couple of these units (which I figure is a photocell) and mount it in another triangular piece you would be in like flint... Really I think it could be done for less than a hundred bucks... I would consider trying it but I am in the process of putting a new roof on my house so I don't have any time right now.

JV

Yes, it can be done for less than $100, assuming you know what you are doing. Were I to build such a contraption it would sell for $400. I have used this concept since 1981 starting with a speedometer/odometer for a super-mileage vehicle, then tachometers, and more recently for a golf shaft frequency meter. It's pretty simple, assuming you know the trick to get the display to read whatever units you desire (m/s, mph, etc) (no processor required) :) It could be built for good precision, it's accuracy would require calibration.

Dave

td873
04-11-2005, 12:05 PM
Thank you very much everyone.
Let me see if I have gotten this down correctly.
1., 2., 3.

All correct.

I have a few more questions:
1. Can I calibrate my gun so it could actually read a higher speed than the actual speed?
2. Are you focusing on the cueball when it leaves the cue, or the cue ball when it strikes the 1 ball, when you obtain your reading?
3. Should I move the radar gun depending on where the breakers break from?

1. I don't believe so, it's all programmed and solid state. Just measure your angles and use their cosines to add back in the error.
2. While the ball is in travel. If you point at the tip or at the pack, you might get false readings. Point at a spot between the two.
3. Yes. Try to use the same angles for all breakers if you are doing a comparison.


Thomas, does your gun come with a tripod, it cannot read to 1 decimal place, can it?
I found this company which rents out radar guns and related equipments, http://www.stalkerradar.com/rental.shtml, have any of you heard of them?
[...]
I am thinking about using it in an application similar to that of the Sardo's in the US open and Vegas, I need something reliable, durable, and consistent.

My machine does not measure to decimals. But when you take an average over a large number of breaks, you can still feel fairly comforable with the results. It does not come with a tripod.

The rental is virtually the same technology that I use, except it has more bells and whistles. Looks good if you want to show the results on a big board. Mine can't do that without modification. However, mine was only $140.00 - plus it's light, easy to use, and I don't have to send it back ;)

Good luck,

-td

X Breaker
04-11-2005, 12:50 PM
All correct.


1. I don't believe so, it's all programmed and solid state. Just measure your angles and use their cosines to add back in the error.
2. While the ball is in travel. If you point at the tip or at the pack, you might get false readings. Point at a spot between the two.
3. Yes. Try to use the same angles for all breakers if you are doing a comparison.


My machine does not measure to decimals. But when you take an average over a large number of breaks, you can still feel fairly comforable with the results. It does not come with a tripod.

The rental is virtually the same technology that I use, except it has more bells and whistles. Looks good if you want to show the results on a big board. Mine can't do that without modification. However, mine was only $140.00 - plus it's light, easy to use, and I don't have to send it back ;)

Good luck,

-td

The cosine is the horizontal vector component, is that correct?

So, I guess it will be alright if I focus at the same point between the cue ball and the rack for all the players--if I focus on a point closer to the head string, I can get a slightly higher reading than if I use a point closer to the rack, although I doubt the difference would be significant.

Since player break from many different spots, which points do you pick as your reference?

Thank you.

Richard

td873
04-11-2005, 01:47 PM
The cosine is the horizontal vector component, is that correct?
if I focus on a point closer to the head string, I can get a slightly higher reading than if I use a point closer to the rack, although I doubt the difference would be significant. Richard
The cosine effect applies twice here, once for the horizontal component, and once for the vertical component. [You are creating error in two planes, X and Y] If you don't change the height of your gun, you should have the same vertical error component for every breaker. I always point at the center spot of the table for every breaker - my location along the back of the table might be different though.

Note: I think that if you point the gun closer to the headstring, you will get a slightly LOWER reading than actual. The reason for this is that pointing closer to the headstring creates a larger angle of incidence from from the ball to the gun. The cosine of this angle is the accuracy of the reading. The bigger the angle, the less accurate the reading.

http://td873.enteronline.net/pic_1.jpg

Cos(17)= 95.63% accurate
Cos(22)= 92.72% accurate
Cos(30)= 86.60% accurate

This is also the way that the horizontal component works. The more angle between you and the breaker, the more error is created in the reading.

-td

chefjeff
04-11-2005, 01:47 PM
Didn't Bob Byrne (with some others) take off the end rail, measure the distance on the floor that the ball traveled past the end of the slate, and then figured the speed?

Seems like I read this in BD, but my memory may, again, be playing tricks on me.

Not as much fun a smashing the rack, but cheaper anyway.

Jeff Livingston

drivermaker
04-11-2005, 02:59 PM
Let me see if I have gotten this down correctly.

1. If the gun is placed in front of, or right behind of the breaker, and is held as level as possible, then it will produce the most accurate result.

3. Should I move the radar gun depending on where the breakers break from?

If I focus on the cueball at the moment when it strikes the pack, will the reading be accurate if the cue ball jumps up, when it strikes the 1 ball?

Richard


The Big Buddha at Bushnell said that you wouldn't get as accurate a read from behind because arm swing and the cue itself would be picked up and distort the results. You don't get anywhere near as much from the front.

Screw where the breakers break from. This is a "BREAK SPEED CONTEST", not a "how many balls you can make on the break for a runout" contest. Make ALL of them break from the same place. There's no reason for a contest like this why they can't break right from the head spot in order that you don't have to jump around like a jack rabbit with the gun.

The Buddha did say there can also be distortion at times from the rack balls spreading out.

woody_968
04-11-2005, 03:10 PM
While at a recent siminar Jerry Breiseth and Mark Wilson both had radar guns. When George Breedlove hit one break both had their guns on, one if front and one in back, they both registered 37.7mph. I would be surprised if both were on the exact same vertical and horizontal placements. Not saying what has been written here is not true, just thought it was interesting.

I also noticed that several times Jerry actually layed the gun on the table beside the cueball and then picked it up right after the break. Wouldnt this be the most accurate reading?

Rackin_Zack
04-11-2005, 03:23 PM
While at a recent siminar Jerry Breiseth and Mark Wilson both had radar guns. When George Breedlove hit one break both had their guns on, one if front and one in back, they both registered 37.7mph. I would be surprised if both were on the exact same vertical and horizontal placements. Not saying what has been written here is not true, just thought it was interesting.

I also noticed that several times Jerry actually layed the gun on the table beside the cueball and then picked it up right after the break. Wouldnt this be the most accurate reading?

Ah, 37.7 mph is nothing! I'm pretty sure George was impressed/intimidated by my 15 mph break!

woody_968
04-11-2005, 03:32 PM
Ah, 37.7 mph is nothing! I'm pretty sure George was impressed/intimidated by my 15 mph break!

I think we all were :)

drivermaker
04-11-2005, 03:34 PM
While at a recent siminar Jerry Breiseth and Mark Wilson both had radar guns. When George Breedlove hit one break both had their guns on, one if front and one in back, they both registered 37.7mph. I would be surprised if both were on the exact same vertical and horizontal placements. Not saying what has been written here is not true, just thought it was interesting.

I also noticed that several times Jerry actually layed the gun on the table beside the cueball and then picked it up right after the break. Wouldnt this be the most accurate reading?


Do you recall who the manufacturer was and what model was used? If not, can you get in touch with either or both of them to find out?

woody_968
04-11-2005, 03:39 PM
Do you recall who the manufacturer was and what model was used? If not, can you get in touch with either or both of them to find out?

I can contact them and ask them what they use,,, I was going to anyway as I will be getting one soon for lessons.

Mark has one like what is used at a ball park,,, goes with the theme of the room. Has the big display and all.

Woody

Hal
04-12-2005, 12:16 AM
I once read that David Howard had the fastest break on tour. But that was a long long time ago.

chefjeff
04-12-2005, 07:22 AM
I think he is looking to set this up in a show or something like that, not just to conduct an experiment.

Maybe he could put bells, or cups, or ala Massey, a boot and give prizes found in each when a breaker lands in them.

Jeff Livingston

Williebetmore
04-12-2005, 10:39 AM
Maybe he could put bells, or cups, or ala Massey, a boot and give prizes found in each when a breaker lands in them.

Jeff Livingston

Jeff,
Not a very good way to measure speed, or even compare breaks. I believe it has been shown that the cue ball slows down (someone correct me if they know differently) even before hitting the one-ball on a power break. By the time the cue ball reaches the absent foot rail area, surely it has slowed further. Wouldn't the amount of slowing depend on the amount of forward or reverse spin placed on the cue ball?? Too many variables for me - I like the idea of a radar gun with fixed placement. Ceebee used to sell one on his website, but I believe it had problems with fluorescent light, so he wouldn't sell me one until the bugs are fixed.

drivermaker
04-12-2005, 11:13 AM
[QUOTE=Williebetmore} I believe it has been shown that the cue ball slows down (someone correct me if they know differently) even before hitting the one-ball on a power break. Wouldn't the amount of slowing depend on the amount of forward or reverse spin placed on the cue ball?? Too many variables for me - I like the idea of a radar gun with fixed placement. [/QUOTE]


The CB starts slowing down almost immediately after leaving the tip of the cue, as does a baseball the further it gets from the pitchers finger tips. (Why is it that after you hit 40 years old, this same slowing down of the aging process works in total reverse and turns into an increase of speed)?

I'm not sure that spin has any chance to even take.

The radar gun should have a fixed placement and so should the launching point for the CB. BTW, the shortest distance between the front ball in a rack and the CB is on the head spot. Once you start moving out to the side along the headstring, the distance increases to about 6" or more once you're on the rail. (if you don't believe me...measure it). The increased distance would also lead to a slow down.

T411
04-12-2005, 11:31 AM
Other than to find out who has the fasted break or how fast your break is, what does it matter? I do not think that a good break necessarily has anything to do with ones effort to increase ones break speed. I may be able to break as fast as anyone, is that going to make my break great? :confused:

DaveK
04-12-2005, 11:53 AM
Jeff,
Not a very good way to measure speed, or even compare breaks. I believe it has been shown that the cue ball slows down (someone correct me if they know differently) even before hitting the one-ball on a power break. By the time the cue ball reaches the absent foot rail area, surely it has slowed further. Wouldn't the amount of slowing depend on the amount of forward or reverse spin placed on the cue ball?? Too many variables for me - I like the idea of a radar gun with fixed placement. Ceebee used to sell one on his website, but I believe it had problems with fluorescent light, so he wouldn't sell me one until the bugs are fixed.

Actually it is a very GOOD way to measure the speed of the cue ball (agreed, at the point where it leaves the 'table'). If the table and ground are both nicely 'horizontal' (as compared to gravity), the calculation does not involve the measurement of time, rather you measure distance (the time unit enters the equation as the accelleration due to gravity). My guess (too lazy to do the calculations) is that you can achieve a higher degree of precision measuring the distance. What I mean is, when measuring the distance you should be able to achieve +- 1mm or so. This would equate to a very small time measurement to get the same speed measurement, perhaps in the 1000ths of seconds (again, I did not run the numbers). You might need to know the precise accelleration due to gravity at the table, it will vary a bit from place to place. I am inclined to believe that this method could be more accurate and precise than a radar gun, especially a cheap or uncalibrated unit, but would want to do a bit more research before placing a wager.

Also, if it is felt that the speed is better measured at the foot string, or at the head spot, you just leave 1 or 2 slates off the table :)

Dave, who will not be doing this at home, that concrete wall will get in the way every time !

drivermaker
04-12-2005, 01:12 PM
Actually it is a very GOOD way to measure the speed of the cue ball (agreed, at the point where it leaves the 'table'). If the table and ground are both nicely 'horizontal' (as compared to gravity), the calculation does not involve the measurement of time, rather you measure distance (the time unit enters the equation as the accelleration due to gravity). My guess (too lazy to do the calculations) is that you can achieve a higher degree of precision measuring the distance. What I mean is, when measuring the distance you should be able to achieve +- 1mm or so. This would equate to a very small time measurement to get the same speed measurement, perhaps in the 1000ths of seconds (again, I did not run the numbers). You might need to know the precise accelleration due to gravity at the table, it will vary a bit from place to place. I am inclined to believe that this method could be more accurate and precise than a radar gun, especially a cheap or uncalibrated unit, but would want to do a bit more research before placing a wager.



I think the distance measurement could become totally skewed and moot once the master blasters figured out how to get a little air time into their hit to reduce initial friction.

drivermaker
04-12-2005, 01:16 PM
Other than to find out who has the fasted break or how fast your break is, what does it matter? I do not think that a good break necessarily has anything to do with ones effort to increase ones break speed. I may be able to break as fast as anyone, is that going to make my break great? :confused:


The World's Long Drive Contest in golf surely doesn't mean that they're better players or their long drive will necessarily lead to lower scores. But they're both a lot of fun to watch just to see the awesome speed and power, along with sounds in pool.

DaveK
04-12-2005, 01:31 PM
I think the distance measurement could become totally skewed and moot once the master blasters figured out how to get a little air time into their hit to reduce initial friction.

Again, I have not run the numbers, but any airtime would add a vertical component opposite to what is being measured (the drop off the table), so the result could be worse (lower 'horizontal' speed). This effect would be played with by the 'master blasters', something that would be a detriment to their breaks (that is unless you like launching the cue ball off the table).

So here's another idea, play the CB into a single object ball on the headspot, and measure it's (OB) distance to fall. In that way one must keep control of the CB, and poor hits on the OB would be reflected in both the absolute distance the OB travels, and it's direction.

OK, this is getting too convoluted, maybe a radar gun is better, even with it's limitations ...

I've thought about using a buddys golf ball launch monitor, but it is set up to measure speeds of balls from perhaps 50 to 150 mph. I want to try it out though, even if it's to prove to myself it won't work. One cool thing about this device is that if it could measure such a slow speed, it would also be able to measure spin rate (for top or bottom, it would not do so well with siding spin rates).

Dave

woody_968
04-12-2005, 02:18 PM
Other than to find out who has the fasted break or how fast your break is, what does it matter? I do not think that a good break necessarily has anything to do with ones effort to increase ones break speed. I may be able to break as fast as anyone, is that going to make my break great? :confused:

Break speed is only one small part of the break, and yes its more important to have a solid hit with cueball control than to hit them hard. But at some point to really dominate a nine ball game one may need to learn how to increase their speed. The use of a speed gun can be very usefull to work on this. That way you can find out techniques that may or may not increase speed.

X Breaker
04-12-2005, 04:11 PM
Thank you for all the replies. All of you have been very helpful, much appreciated.

Does anyone remember where was the gun pointed at during the Sardo contest?

I think the breaker was allowed to break from anywhere on the table along the head string, is that correct?

If my memory serves me correctly, during the Saroo contest in Vegas, the gun was mounted on a tripod and was located somewhere in front of the breaker, not from behind or the side, is that right?

Thank you.

Richard

chefjeff
04-13-2005, 05:58 AM
Jeff,
Not a very good way to measure speed, or even compare breaks. I believe it has been shown that the cue ball slows down (someone correct me if they know differently) even before hitting the one-ball on a power break. By the time the cue ball reaches the absent foot rail area, surely it has slowed further. Wouldn't the amount of slowing depend on the amount of forward or reverse spin placed on the cue ball?? Too many variables for me - I like the idea of a radar gun with fixed placement. Ceebee used to sell one on his website, but I believe it had problems with fluorescent light, so he wouldn't sell me one until the bugs are fixed.

I'm not sure about that, Dr. Willie. It seems once the realtionship was established between the distance traveled and the speed, the rest doesn't matter. If it goes so far, it must be going so fast. But I could be wrong. :eek:

Maybe moving the cueball two diamonds toward the rack (= distance from the head ball to the foot rail) would eliminate any additional errors caused by the spin and distance traveled on the cloth. But then only the side break would allow a good stance.

How about using ceebee's practice rack thingy and put a sensor on one of the cords that measures the amount of force that hits the rack?

Where's Mr. Jewett? We need some physics here. :confused:

Jeff Livingston

drivermaker
04-13-2005, 06:26 AM
Where's Mr. Jewett? We need some physics here. :confused:



Only if he can control himself to this issue and not start dragging it into the actual shooting process and how to play the game. :eek:

vapoolplayer
04-13-2005, 06:35 AM
i'm just gonna jump right in here...............


does break spead actually really matter anyway????

you hit the 1 ball...........you make a ball..........you have a good spread............you leave yourself to where you will more than likely have a shot................5mph or 30mph..........all the same.

VAP

mjantti
04-13-2005, 06:38 AM
If you look closely at the cloth, you can see the white "burn" marks where the cueball took off and where it landed first. Watching those rare landing marks tells me that the cueball touches only once or twice the cloth during a high speed break, which suggests that the speed shouldn't decrease much before hitting the rack. The first 2-4' the cueball is usually airborne and in some very hard breaks the cueball doesn't even touch the cloth at all before hitting the rack. A couple of WPC slow motions has shown this...

So, I wouldn't say the cueball slows down much on breaks before hitting the rack...

drivermaker
04-13-2005, 06:47 AM
So, I wouldn't say the cueball slows down much on breaks before hitting the rack...


Even when you're playing anywhere along the equatorial line due to gravity or in the N/S hemisphere from the Coriolis Force? :p :D

drivermaker
04-13-2005, 06:48 AM
i'm just gonna jump right in here...............


does break spead actually really matter anyway????

you hit the 1 ball...........you make a ball..........you have a good spread............you leave yourself to where you will more than likely have a shot................5mph or 30mph..........all the same.

VAP


Ask Keith McCready...

chefjeff
04-13-2005, 07:39 AM
OK, how about a feedback device similar to the one at the carnival where you swing a sledge hammer and ring the bell?

Put an 2-1/2 elbow pipe on the cloth with a clear tube attached to it extending upward x feet. The object is to hit the cueball into the pipe and have it roll up the tube as far as possible. Graduated marks on the tube would indicate the speed. At the top of the tube would be the bell, which would require x mph to hit.

This would require a straight, powerful hit and would be a cool visual.

Step right up, impress your girl, win a cupie doll....

Jeff Livingston

T411
04-13-2005, 07:42 AM
Break speed is only one small part of the break, and yes its more important to have a solid hit with cueball control than to hit them hard. But at some point to really dominate a nine ball game one may need to learn how to increase their speed. The use of a speed gun can be very usefull to work on this. That way you can find out techniques that may or may not increase speed.

I think that you are right in the fact that one may need to increase their speed. I do not think that a great break speed and a great break, necessarily go hand in hand. What works for some may not work for another. I do not think a person needs a radar gun to know if his or her break speed is increased or decreased, you can feel what your putting into the stroke. As fare as techniques that may increase or decrease speed? Well the end result of whatever power that you put in the break is evident. Does the number that registers on the gun matter? drivermaker said that it could be fun tool to see who can hit the ball the hardest; I can go with that. But other than that, is it really a good tool to make your break better?

mjantti
04-13-2005, 07:53 AM
Even when you're playing anywhere along the equatorial line due to gravity or in the N/S hemisphere from the Coriolis Force? :p :D

Actually, Coriolis Force will make the cueball curve on it's way to the rack... that's why I always get that off-center hit on the head ball ;) Damn you rotating earth...

drivermaker
04-13-2005, 08:21 AM
Actually, Coriolis Force will make the cueball curve on it's way to the rack... that's why I always get that off-center hit on the head ball ;) Damn you rotating earth...


That's easily corrected by putting counteracting english on the CB....hmmmm, now which way does it go in the N, clockwise or counter clockwise....time to go to the toilet anyway, I'll figure it out there. ;)

DaveK
04-13-2005, 10:58 AM
Actually, Coriolis Force will make the cueball curve on it's way to the rack... that's why I always get that off-center hit on the head ball ;) Damn you rotating earth...

You play with a degree of precision with which I am not familiar ... ;)

Now if you hit the break shot with such power that time slows down I'll be mighty impressed, and you won't have to worry about Coriolis so much either ...

Dave

thecyclone@btin
04-16-2005, 12:27 AM
hi i am interested in getting hold of a speed gun, can you help........ the cyclone

drivermaker
04-16-2005, 05:00 AM
hi i am interested in getting hold of a speed gun, can you help........ the cyclone


The answer lies within this thread....also try ebay

X Breaker
04-17-2005, 02:40 AM
Thank you for all the wonderful comments.

Are any of you attending the BCA in May?

drivermaker
04-17-2005, 08:18 AM
Thank you for all the wonderful comments.




So...which one have you decided to invest in...the Jugs or another less expensive model?

X Breaker
04-17-2005, 12:54 PM
So...which one have you decided to invest in...the Jugs or another less expensive model?

I am seriously considering the models which can read the decimals. Although they are more expensive, they serve to read the subtle differences when reading a relatively low velocity such as the break velocity. 26mph and 26.4mph may not mean much to most people, but it is an indication of an advantage when you are looking to find out, for instance, the difference the weight of the breaker can make to your break. This is just one of the many applications in which the radar gun can be useful.

I am still trying to learn all the details about where to point the gun at and how to get the most consistent and accurate reading. I would like to allow the player to break from any position along or behind the head string. I am doing this because this can help the player to find a point on the table whereas the player can obtain the highest break velocity. The difference may only be .2 mph--yet it is still a significant difference considering that it can make the difference between a ball hanging in front of the pocket and a ball dropping in the pocket.

Most players like to see how many balls fall when trying out a break cue. This method is very misleading because luck plays a hugh factor in the outcome. Some players listen to the sound of the break--when they hear a loud noise, they think they are having a powerful break--again, it is not scientific. As a matter of fact, a lot of noise represents a lot of energy lost in the form of sound waves--does it offer a guarantee of higher break velocity is what I like to know.

Since kinetic energy is 1/2 mass times the square of velocity, the break velocity is the key factor to obtain maximum energy transferred to the cue ball. My idea is to find out scientifically how such a maximum energy transfer could be possible for each player who participates in my experiment. I am also interested in learning the relationships between shaft taper, tip hardness, balance, and joint configuration versus break velocity.

I like to ask the following questions and hopefully, obtain my answers with the help of a radar gun.

1. Does a stiff taper offer higher break velocity?
2. Does a phenolic tip offer higher break velocity? If so, how much?
3. What is the optium weight for maximum break velocity for each player?
4. Does the joint make a difference?
5. Will a jump/break cue break less solid than a full breaking cue because of the difference in balance and the presence of an extra quick release joint?
6. Will a player break better from a certain point on the table consistently? If so, where is it? And how much higher is the increase in velocity?

This is not intended to be a contest on who breaks the fastest, this expeiment is intended to help the players to learn more about their games and their equipment; in other words, to know more about themselves--it is meant to offer the players a solid proof that what they are using/buying is really the best equipment for the job, and where they are breaking from and how they are breaking is really the best way to go--based on scientific data, rather than outcomes based on luck or personal impression based on noise level.

When one knows these things with certainty, one can always break with the highest breaking velocity within one's capacity.

Thank you very much for all your assistance.

PS: How many of you are going to the BCA in May? Drivermaker, are you going to be there?

Richard

drivermaker
04-17-2005, 01:47 PM
I am also interested in learning the relationships between shaft taper, tip hardness, balance, and joint configuration versus break velocity.

I like to ask the following questions and hopefully, obtain my answers with the help of a radar gun.

1. Does a stiff taper offer higher break velocity?
2. Does a phenolic tip offer higher break velocity? If so, how much?
3. What is the optium weight for maximum break velocity for each player?
4. Does the joint make a difference?
5. Will a jump/break cue break less solid than a full breaking cue because of the difference in balance and the presence of an extra quick release joint?
6. Will a player break better from a certain point on the table consistently? If so, where is it? And how much higher is the increase in velocity?


PS: How many of you are going to the BCA in May? Drivermaker, are you going to be there?

Richard


Interesting questions and the answers will be also, if break speed in itself will divulge them. Nay...I won't be going.

td873
04-17-2005, 05:19 PM
Since kinetic energy is 1/2 mass times the square of velocity, the break velocity is the key factor to obtain maximum energy transferred to the cue ball.

If you are implying that the stick's velocity is the key factor in obtaining maximum kinetic energy ("KE"), then you are a little off target. Since there are two variables, you can change either one to obtain more KE. As noted below, a heavy cue stick travelling slower can have the same KE as a lighter stick travelling faster...

Maximum energy transferred to the cue ball does not equate to maximum energy imparted to the rack. Any off center hit will cause angular velocity, which in turn results in less 'speed'. Further, angled cue sticks cause energy to be transferred to the slate, again resulting in less 'speed'. There are other considerations as well, such as the tip material (as you mentioned below).

I am also interested in learning the relationships between shaft taper, tip hardness, balance, and joint configuration versus break velocity.
What about shaft diameter, cue weight, vertical angle, and break location (breaking head on is a shorter distance than from the rail)?

Just some comments:
There are two schools of thought regarding break cues: heavy cues and light ones. A heavy cue stick travelling slower can result in as much force as a lighter cue stick travelling faster. However, the current trend is to use a cue stick closer to the weight of your playing cue, or perhaps a hair lighter...

1. Does a stiff taper offer higher break velocity?
How would you verify this? If you change the taper on a cue, you would change the weight, resulting in different measurements...
2. Does a phenolic tip offer higher break velocity? If so, how much?
A phenolic tip will absorb less of the impact (as compared to a softer tip). This in turn will result in more energy going somewhere. It could result in more velocity, or a jumping cue ball, or more spin on the cue ball, etc. [I did an experiment on this, will post results below.]
3. What is the optium weight for maximum break velocity for each player?
As above, a player may have two cues that result in exactly the same velocity, one heavy and one light. The player will most likely be able to accelerate a lighter cue more than the heavy one over the course of the forward swing, but they might both result in the same KE.
4. Does the joint make a difference?
Look up the speed of vibrations through wood. The cue tip might be in contact with the cue ball for .001 sec. The longitudinal (compression) waves will most likely not make it through the joint and back in time for the joint to make a difference in this short time.
5. Will a jump/break cue break less solid than a full breaking cue because of the difference in balance and the presence of an extra quick release joint?
Mine did.
6. Will a player break better from a certain point on the table consistently? If so, where is it? And how much higher is the increase in velocity?
There have been statistical studies showing that breaking from the rail increases balls made on the break. I don't believe that break speed was a consideration in that study. I don't think that breaking from one place on the table affects velocity. A player has a maximum break speed no matter where they align. (i.e., if Hillbilly Bryant can break 35 MPH from the center spot, he can break 35 MPH from the rail...)
it is meant to offer the players a solid proof that what they are using/buying is really the best equipment for the job
I think that you would need a Iron Willy type of machine and a bunch of different sticks for any reliability. Simply measuring breaks of different people will yield very little helpful information. Although it will provide a nice statistical analysis of break speeds...

-td

td873
04-17-2005, 05:22 PM
I have a number of cues that I've used for breaking over the years. So
one day I decided to do a little experiment with a few of them. I grabbed the following cues:
J&J jump break with phenolic tip (quick release)
Bob Frey - shaft (1) with phenolic tip (5/16 x 14 piloted joint - not J/B)
Bob Frey (same) - shaft (2) with Moori Medium
Big Log - 20 oz house cue (Dufferin)
Small log - 18 oz house cue (Dufferin)

I ran to my home room and took out my radar gun and had my good buddy
time all my breaks. I did around 10 breaks for each stick, and kept
highly confidential and trade secret protected scientific data on the
back of a beverage napkin. ;)

Speed: *all breaks counted, even if the cue ball went flying to Omaha*
For me, the best speed breaks came from the Frey with Phenolic tip.
I had around a 3-5 MPH slower breaks when using the J&J with phenolic tip. The other cues were just a bit under the J&J, but once or twice I was in the same range. This amounted to about a 15-20% increase in speed. [max with J&J was 22, max with Frey was 25, max with others was 21 (but only did that once); the averages had about the same ranges]

There was almost no difference between Frey with Moori and small log,
but the big log was 1-2 MPH slower. (I'm probably too weak to properly
wield the big log, lol). Overall: Frey with phenolic was fastest, then
J&J, then pick your poison.

-td

X Breaker
04-17-2005, 10:23 PM
If you are implying that the stick's velocity is the key factor in obtaining maximum kinetic energy ("KE"), then you are a little off target. Since there are two variables, you can change either one to obtain more KE. As noted below, a heavy cue stick travelling slower can have the same KE as a lighter stick travelling faster...

Yes, you are right. You can have an identical number. My point was made based on the fact that KE is proportional to the square of the velocity and directly proportional to the mass; therefore, a slight increse in velocity will have a bigger impact on KE than an equal increase in mass. Besides, the range of mass of a breaking cue is very narrow, most likely from 18 to 21 oz, while break velocity can go from less than15mph to over 30 mph. That is why I consider the velocity variable more crucial.

Maximum energy transferred to the cue ball does not equate to maximum energy imparted to the rack. Any off center hit will cause angular velocity, which in turn results in less 'speed'. Further, angled cue sticks cause energy to be transferred to the slate, again resulting in less 'speed'. There are other considerations as well, such as the tip material (as you mentioned below).

I really learn a lot from the points you made. Thank you. I am however not entirely sure if the angular velocity can decrease the linear velocity to a significant extend. Besides, I am interested in knowing what would result in the maximum velocity transferred to the cue ball for each player. I believe a player is used to breaking in a certain way and so the variations of the breaking angle and breaking spin might be quite consistent from cue to cue for that particular player. Having said that, it is possible that a different cue may drastically change the technique of the player, it is something I am very interested to find out. Do you think you break differently with different cue?

about shaft diameter, cue weight, vertical angle, and break location (breaking head on is a shorter distance than from the rail)?

Yes, it is true that the above mentioned distance is the shortest. However, since body position is different for the breaker breaking from the center, is it possible that the breaker might not be able to generate as much acceleration from this position?

Just some comments:
There are two schools of thought regarding break cues: heavy cues and light ones. A heavy cue stick travelling slower can result in as much force as a lighter cue stick travelling faster. However, the current trend is to use a cue stick closer to the weight of your playing cue, or perhaps a hair lighter...

In my opinion, most players do not want to use a heavy breaking cue playing pool for long hours. If a lighter cue is preferred, I like to find out which weight is the best to achieve maximum breaking velocity for each player.

1. Does a stiff taper offer higher break velocity?
How would you verify this? If you change the taper on a cue, you would change the weight, resulting in different measurements...

Good point. If I have two shafts with identical weight but different density, wouldn't they be useful in serving my purpose?


2. Does a phenolic tip offer higher break velocity? If so, how much?
A phenolic tip will absorb less of the impact (as compared to a softer tip). This in turn will result in more energy going somewhere. It could result in more velocity, or a jumping cue ball, or more spin on the cue ball, etc. [I did an experiment on this, will post results below.]

Yes, where did the energy go is the question I suppose. Did they dissipate mainly in the form of sound, or a vertical vector component which jumps the ball off the table, or more energy into breaking the balls?

3. What is the optium weight for maximum break velocity for each player?
As above, a player may have two cues that result in exactly the same velocity, one heavy and one light. The player will most likely be able to accelerate a lighter cue more than the heavy one over the course of the forward swing, but they might both result in the same KE.

If I let you try breaking with cues ranging from 17 to 22 oz, and show you the breaking velocity obtained from each cue, will you pick the cue with the weight which offers you the highest velocity? I think because the range of weight is so narrow, and because it is only linear propotional to KE, it is easier to obtain a maximum KE with an increase in velocity than an increse in weight.

If you look at the differential of KE versus mass and velocity respectively,

d KE / d mass = 1/2 velocity square provided velocity is a constant. i.e. d KE/ d mass is a constant.

d KE/ d velocity = mass times velocity provided mass is a constant. i.e. d KE/ d velocity is a linear equation dependent on velocity, which is a variable.

It tells me that a change in KE is constant versus a change in mass provided that velocity is a constant, i.e they are independent provided velocity is constant;

however, a change in KE versus a change in velocity is a linear equation provided that mass is a constant, i.e. they are dependent in a linear relationship even if the mass is constant.

In layman's term, let's assume that you can move the cue with the same velocity at 18, 19, or 20 oz, you get the same increase in energy going form 19oz to 20oz or from 18oz to 19oz. Whereas if you look at the increase in energy with a particular weight, you can see that the amount of increase of energy is dependent on the amount of increase of velocity and the velocity itself. It is not a constant.

That is why I stated that velocity is the key factor.

4. Does the joint make a difference?
Look up the speed of vibrations through wood. The cue tip might be in contact with the cue ball for .001 sec. The longitudinal (compression) waves will most likely not make it through the joint and back in time for the joint to make a difference in this short time.

I am not too sure about that. For example, if the joint of the cue is lose, would that have any effect on the break? Now, if the joint is not tight enough, would that result in energy lost? Do you believe that some joints are tighter than others, if you do, do you think that it will affect the break?

5. Will a jump/break cue break less solid than a full breaking cue because of the difference in balance and the presence of an extra quick release joint?
Mine did.
6. Will a player break better from a certain point on the table consistently? If so, where is it? And how much higher is the increase in velocity?
There have been statistical studies showing that breaking from the rail increases balls made on the break. I don't believe that break speed was a consideration in that study. I don't think that breaking from one place on the table affects velocity. A player has a maximum break speed no matter where they align. (i.e., if Hillbilly Bryant can break 35 MPH from the center spot, he can break 35 MPH from the rail...)

I agree making balls off the break is not only dependent on break velocity. However, I am interested in finding out if there is indeed a relationship between breaking position and breaking velocity. I personally have a weaker break breaking from the center of the table--it may just be me--but I would like to help players to find out if there is a stronger side to their breaks due to body alignment, machanic or whatever it might be.

think that you would need a Iron Willy type of machine and a bunch of different sticks for any reliability. Simply measuring breaks of different people will yield very little helpful information. Although it will provide a nice statistical analysis of break speeds...

-td

You are right. Your suggestions and comments have been very informative. I have been thinking about this for a long time but I have to say I have missed a lot of key ideas until I read your posts.

What do you think about the following scenerio?

You go to a booth during a trade show and there are a lot of breaking cues made by the same cue makers--some with leather tips, others with phenolic tips; some with pro taper, others with stiffer taper; some heavy, others light.

You are offered to try them all, and to compare them, plus you are also offered to compare them with your own breaking cue, based on the elements I stated.

The point of the experiment is not just to sell you a cue, but to let you find out what is best for *you*. The data from the radar gun are offered to you so you can make an informed decision as to whether you need another breaking cue, if you do, which one should you choose in terms of taper, tip, weight..etc

Richard<--just typed the longest post in his whole life...

drivermaker
04-18-2005, 05:25 AM
I have a number of cues that I've used for breaking over the years. So
one day I decided to do a little experiment with a few of them. I grabbed the following cues:
J&J jump break with phenolic tip (quick release)
Bob Frey - shaft (1) with phenolic tip (5/16 x 14 piloted joint - not J/B)
Bob Frey (same) - shaft (2) with Moori Medium
Big Log - 20 oz house cue (Dufferin)
Small log - 18 oz house cue (Dufferin)
-td


What were the weights of the Frey's and J&J? And do either of them have weight bolts that can be taken out and replaced with either heavier or lighter ones to go up and down the ladder to get different speed results, along with # of balls made, CB control, and rack spread?

ceebee
04-18-2005, 06:29 AM
[QUOTE Originally Posted by td873
I think that you would need a Iron Willy type of machine and a bunch of different sticks for any reliability. -td End QUOTE]

Predator has already done this work for you

td873
04-18-2005, 08:16 AM
[YOUR MATHEMATICAL ANALYSIS +] In layman's term, let's assume that you can move the cue with the same velocity at 18, 19, or 20 oz, you get the same increase in energy going form 19oz to 20oz or from 18oz to 19oz.
Although the KE increase is linear as you suggest, it is more important to note the impact of this on the cue ball's speed, rather than the KE before impact. Accordingly, where you increase weight and keep velocity constant, the cue ball's speed increase will NOT be linear. Rather, it is based on the square root of the stick/ball ratio. Increasing stick weight increases this ratio, therefore, this ball speed plot cannot be linear.
Whereas if you look at the increase in energy with a particular weight, you can see that the amount of increase of energy is dependent on the amount of increase of velocity and the velocity itself. It is not a constant.
Again, increasing KE just before contact is not the critiacal issue. Solving the system after contact is. Using the same analysis as above, where you increase the velocity, and keep mass of the cue the same, the increase in cue ball speed will be LINEAR [and the cue ball will be about 1.732 MPH faster for each 1 MPH increase in stick speed (cue ball = 6oz, cue stick = 18oz here)]

KE is proportional to the square of the velocity and directly proportional to the mass; therefore, a slight increse in velocity will have a bigger impact on KE.

This ratio of increase in stick velocity only vs. increase in stick weight only is approximately 3:1.

Grab your calculator and verify this since it is early, and I could have my math wrong: the increase in speed of the cue ball based on increasing the speed of the cue stick only (i.e., mass of cue stick stays the same, but speed of the stroke increases) is an increase of 1.732 MPH on the CUE BALL for every 1 MPH increase on the CUE STICK (using 18 oz and 6 oz).

The increase in speed of the cue ball based on increasing the weigh of the cue stick only (i.e., speed of the cue stick stays the same, but mass increases) is an increase of ~.55 MPH on the CUE BALL for every 1 oz increase on the CUE STICK. (This will vary based on the constant stick speed, but for average breakers, .55 is a close approximation).

With this in mind, increasing velocity (in 1 MPH increments) rather than weight (in 1 oz increments) is around a 3:1 improvement (rather than a difference based on the square of the velocity).

[For example, if the joint of the cue is lose, would that have any effect on the break? []Do you believe that some joints are tighter than others, if you do, do you think that it will affect the break?

This will not affect the KE calculation before impact, and will only affect the system at contact. Any loss of energy between the stick and the cue ball will result in less velocity. A loose joint effectively lessens the mass of the 'stick.'

The point of the experiment is not just to sell you a cue, but to let you find out what is best for *you*. The data from the radar gun are offered to you so you can make an informed decision as to whether you need another breaking cue, if you do, which one should you choose in terms of taper, tip, weight..etc

Sounds like a good marketing idea to me...

It should be easy to calculate the best weight/velocity relationship for a particular shooter. For example, if a person's arm just can move faster, their cue speed will never increase. But if they can move a heavier stick at the same speed, their cue ball speed will increase. Also, you should be able to determine how much increase a person has by moving a lighter stick faster...

-td

X Breaker
04-18-2005, 12:26 PM
Although the KE increase is linear as you suggest, it is more important to note the impact of this on the cue ball's speed, rather than the KE before impact. Accordingly, where you increase weight and keep velocity constant, the cue ball's speed increase will NOT be linear. Rather, it is based on the square root of the stick/ball ratio. Increasing stick weight increases this ratio, therefore, this ball speed plot cannot be linear.

Again, increasing KE just before contact is not the critiacal issue. Solving the system after contact is. Using the same analysis as above, where you increase the velocity, and keep mass of the cue the same, the increase in cue ball speed will be LINEAR [and the cue ball will be about 1.732 MPH faster for each 1 MPH increase in stick speed (cue ball = 6oz, cue stick = 18oz here)]


This ratio of increase in stick velocity only vs. increase in stick weight only is approximately 3:1.

Grab your calculator and verify this since it is early, and I could have my math wrong: the increase in speed of the cue ball based on increasing the speed of the cue stick only (i.e., mass of cue stick stays the same, but speed of the stroke increases) is an increase of 1.732 MPH on the CUE BALL for every 1 MPH increase on the CUE STICK (using 18 oz and 6 oz).

The increase in speed of the cue ball based on increasing the weigh of the cue stick only (i.e., speed of the cue stick stays the same, but mass increases) is an increase of ~.55 MPH on the CUE BALL for every 1 oz increase on the CUE STICK. (This will vary based on the constant stick speed, but for average breakers, .55 is a close approximation).

With this in mind, increasing velocity (in 1 MPH increments) rather than weight (in 1 oz increments) is around a 3:1 improvement (rather than a difference based on the square of the velocity).


This will not affect the KE calculation before impact, and will only affect the system at contact. Any loss of energy between the stick and the cue ball will result in less velocity. A loose joint effectively lessens the mass of the 'stick.'



Sounds like a good marketing idea to me...

It should be easy to calculate the best weight/velocity relationship for a particular shooter. For example, if a person's arm just can move faster, their cue speed will never increase. But if they can move a heavier stick at the same speed, their cue ball speed will increase. Also, you should be able to determine how much increase a person has by moving a lighter stick faster...

-td

Thomas:

Thank you. I need more time to think about this in terms of the system after contact.

Are you going to Vegas in May?

Richard