theoretical pool shots vs practical pool shots
- Thread starter justnum
- Start date
Except on very new cloth, there's a "gutter" along the rail from where balls are driven downward into the cloth when they hit the rail. Seems to me it would keep a softly hit ball next to the rail even if that wouldn't quite happen without it.
pj
chgo
my final physics question. do you believe there are more than one configuration for a rack to be frozen.
based on the history robert byrnes says yes. but when i saw magic rack become a standard it made me question the theoretical part of a rack.
magic racks always result in the same configuration and predictable break.
any discussion is welcome
based on the history robert byrnes says yes. but when i saw magic rack become a standard it made me question the theoretical part of a rack.
magic racks always result in the same configuration and predictable break.
any discussion is welcome
Configuration meaning like how balls are frozen next to each other. At a smaller scale the billiard ball is likely rough and perhaps those jigsaw edges impact the which way the balls go creating that random and non repeating break patterns.
What does "how balls are frozen next to each other" mean? For instance, 3 balls frozen together in a triangle - how could that configuration vary?
pj
chgo
for worn out billiard balls with chips and cracks the different grooves are more visible.
do you have an older set that shows more imperfections than youd like?
ill go take pictures
human eye inspection and common sense convince most three balls can only sit one way.
i live in reality perfect balls are tough to make. just imagine those spots as smaller than human eye visible grooves
what magnification has billiard balls been under? i dont have access to lab equipment. i would have gotten some imaging if i could.
So you're wondering if the different amounts of friction at the three contact points can account for the randomness we see breaking "perfectly frozen" racks? My guess is there are lots more significant variables - like for instance, imperfect "freezing" or imperfect rack orientation or differences in the way the cue ball hits the rack even when we try to break the same way. Of all of these, I'm betting friction differences are by far the smallest.
pj
chgo
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no im saying the contact between balls may not be equal because the local flatness of the ball can vary.
the same reason pool tables need leveling. there is wide variation in the set up.
Doesn't sound likely to me. I'm betting there's even more difference in friction.
pj
chgo
I would include temperature and altitude and atmospheric pressure.
I am arguing based on my source Robert Byrnes Trick shot book, the picture posted in this thread claims for a full rack no ball can be consistently called.
why 15 balls is when repeatable physics fails is what interests me
So (far) you speculate friction, ball "flatness", temperature, altitude and atmospheric pressure may play parts in break randomness. I'm still betting all of those things added together are less important than any one of the more obvious culprits (imperfect "freezing", imperfect rack orientation, differences in the way the cue ball hits the rack).
But good luck quantifying those things.
pj
chgo
That book was written way before the template racks were in use (at least widely, I'm not sure if similar like the Sardo rack was out then. You are nitpicking things, between what is theoretically possible to do using a robot with a perfect placement of balls under a theoretically perfect table with magic cushions under some specific atmosphere and what the writer actually meant in the book. I may say it's impossible to throw a needle through the eye of a flying bee, that does not mean we are going to be using a super computer from 2067 to be taking the shot that makes it impossible.
There are a ton of variables to the rack, orientation, how accurate of a hit a human can make, ball sizes in the rack, cloth in the rack area, rail conditions, cloth condition, environment variables, how tightly the balls are together. In some of the racks the balls are actually leaning in towards other balls, in other they may just be sitting next to them without inward pressure, probably a bit of both in a single rack.
There is really no need to think about any of this past in general terms since no human will be able to ever combine all the factors to make a ball off a full rack more than a small number of times. There are too many collisions that can take place on the table with 15 balls being broken apart and too many variables to fully control all those trajectories.
That is why we have % shots, what do you play that has the best chance of a good result.
It's a neat mental exercise that has almost no actual effect on what happens in the real world with a real player on a real table past some general ideas of the area a ball is predicted to go. You can call something like the 1 ball in the side pocket of a break, but can't accurately predict exactly where in the pocket the ball will hit.
That book was my only pool companion for decades until now.
I thought some of the people mentioned in the book had access to better measurement technology nowadays.
My notes from the trickshot book are making the trick shots easier to hit, a lot has not been said about the shots.
As for the scientific nature of a whole rack, this interests me greatly at the academic level.
I thought some of the people mentioned in the book had access to better measurement technology nowadays.
My notes from the trickshot book are making the trick shots easier to hit, a lot has not been said about the shots.
As for the scientific nature of a whole rack, this interests me greatly at the academic level.
If you notice, the CB runs down the rail until it gets to the side pocket, then deflects of the nose of the pocket and diverts off the rail line. There is a trought (mentioned above) on all but new cloth at the side pocket.
The correct way to play this is to use a bit of low and a bit of right on CB and aim a couple of mm outside the side pocket and have the CB massé back onto the rail after the side pocket. This shot works even when the rails are not "dead straight".
The correct way to play this is to use a bit of low and a bit of right on CB and aim a couple of mm outside the side pocket and have the CB massé back onto the rail after the side pocket. This shot works even when the rails are not "dead straight".
If you mean the "gutter" I mentioned, that only exists next to the cushion (the cushion actually creates it). I have noticed slow rolling balls hitting the pocket nose as you say - always thought it was because of imperfect rail alignment.
That's also a good technique for harder hit shots along the rail - they tend to hop a little and get deflected off the overhanging cushion nose.
pj
chgo
When the ball is rolling straight donw the rail, it is actually touching the hairs on the cloth, cause a bit of sidespin.
When the side pocket is encountered, the rolling ball arcs in towards the tip of the far side of the side pocket.
You can see this with a measles ball or striped ball.