Help understanding the faults

BC21

BC21

https://www.playpoolbetter.com
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Patrick Johnson said:
.....

For a stunned CB (as we've been discussing), the OB travels anywhere from 1/10 more than your rule of thumb (for very thin hits) to 7 times farther (for very thick hits). For any hit over 1/2 ball thick the OB travels at least twice as far as your rule of thumb predicts.

Your rule of thumb comes closer for a rolling CB, but still mostly too far off to be useful: the OB travels about 50% farther than your rule predicts for hits over about 1/2 ball thick, up to 5 times as far for very thick hits.

P.S. There's no need to memorize my chart for stun hits - I summarized it in a few simple words. Unfortunately, I don't think the real rule for a rolling CB can be described as simply.

pj
chgo
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In bold. For saftey play you're right, the cb+ob=1 isn't very accurate. But if you're just wanting to control cb speed, the ob speed is irrelevant. So it doesn't matter if cb+ob speed equals 100% of total speed after impact. All that matters is that the rolling cb speed is affected proportionally (though inversely) to the fractional overlap of the shot, meaning a 75% overlap (a 3/4 ball hit) sends the cb away at 75% less speed than it had upon impact with the ob. On a 1/4 ball hit the cb will only lose 25% of its speed. That's a very useful and accurate method of establishing a good feel for cb control. It isn't quite as accurate for controlling both balls, however, as you've already explained.
 
Patrick Johnson

Patrick Johnson

Fish of the Day
Silver Member
BC21 said:
...it doesn't matter if cb+ob speed equals 100% of total speed after impact. All that matters is that the rolling cb speed is affected proportionally (though inversely) to the fractional overlap of the shot, meaning a 75% overlap (a 3/4 ball hit) sends the cb away at 75% less speed than it had upon impact with the ob. On a 1/4 ball hit the cb will only lose 25% of its speed. That's a very useful and accurate method of establishing a good feel for cb control.
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I agree - it's simple, intuitive and can be very useful. Thanks for pointing it out.

pj
chgo
 
BC21

BC21

https://www.playpoolbetter.com
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Patrick Johnson said:
I agree - it's simple, intuitive and can be very useful. Thanks for pointing it out.

pj
chgo
Click to expand...

Of course, it all boils down to experience. I mean, as you've pointed out, once draw or top or stun is introduced the method is basically rendered useless. That's where experience comes in.

The only reason I hit this speed estimating sidetrack was because the op said he finds the cb whizzing around multiple rails on many shots. That made me think he is shooting a lot of thin cuts due to being out of line, and the cb is traveling a bunch based on the thin hit and not neccesarily excessive speed.
 
BilliardsAbout

BilliardsAbout

BondFanEvents.com
Silver Member
Patrick Johnson said:
No, it's mostly not.

For a stunned CB (as we've been discussing), the OB travels anywhere from 1/10 more than your rule of thumb (for very thin hits) to 7 times farther (for very thick hits). For any hit over 1/2 ball thick the OB travels at least twice as far as your rule of thumb predicts.

Your rule of thumb comes closer for a rolling CB, but still mostly too far off to be useful: the OB travels about 50% farther than your rule predicts for hits over about 1/2 ball thick, up to 5 times as far for very thick hits.

P.S. There's no need to memorize my chart for stun hits - I summarized it in a few simple words. Unfortunately, I don't think the real rule for a rolling CB can be described as simply.

pj
chgo
Click to expand...

I see the confusion, for which I apologize. I'm not suggesting a precise calculation on distance for ob/cb, which many players already have by feel.

Rather, I'm suggesting, for example, for a given ball near the middle of the short rail, where the player is uncomfortable with a thin cut or long bank as an offensive shot, that they may choose from a full hit to send the ob to the far rail opposite, a thin hit to send the cb that way instead, or a half ball hit to send both balls toward the long rails and a challenging bank for the incoming player. The hits determine the relative speeds of the ob and cb following ball impact.
 
Bob Jewett

Bob Jewett

AZB Osmium Member
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Patrick Johnson said:
Yes, just not in the ratios you suggested....
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It is important to note that the quantity everyone is probably interested in is the distance traveled by the two balls. That distance is proportional to the square of the speed of the ball (modified by whatever spin is on the ball).
So, for a stun shot:

45-degree cut, equal speeds, equal distances

30-degree cut (half-ball), speeds in a 1.73:1 ratio (OB faster) and distances in a 3:1 ratio (OB farther)

60-degree cut, speeds in a 1:1.73 ratio (OB slower) and distances in a 1:3 ratio (CB farther)

The distances are only good if the balls do not contact a rail, of course.

If there is follow/draw on the cue ball, things get a lot more complicated. There is a graphical method that allows you to find the final speeds and directions of both balls after the spin takes effect. I described that in two articles in 2001 that you can find here:

http://www.sfbilliards.com/articles/2001.pdf

A simple rule of thumb is that if you hit a ball full with follow, the cue ball will go 1/6 as far as the object ball. The simple version of the theory actually predicts a ratio of 4/25. There are enough minor effects that 1/6 = 4/24 is close enough and you have to see what the actual number is for your equipment anyway.
 
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FranCrimi

AzB Silver Member
Silver Member
bratnikotin said:
Apologies, for not providing more details

I am above novice level .. so stance, bridge .. I am sort of OK on that front.
And, yes, I meant "shooting fast" as a speed of a cue ball, directly related to "speed" of the cue.
Now, I do not understand what is it I do, when I want to shoot "fast" and NOT hard, and instead, I end up shooting hard. So, the object ball swiftly goes to the pocket or to chosen target, but ... at the same time, cue ball makes few rounds around the table, and I would want it to, maybe just, run q quarter table off, keeping the swiftness of the object ball.
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Sounds like a timing issue to me. Take your cue back slowly, even if you're trying to shoot fast. What that person watching you may be seeing is that you may be poking the ball sometimes which is because you are bringing the cue back too fast and your stroke timing is off. If you keep changing the speed of your backstroke, your forward stroke timing will get affected.
 
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