aiming

[nrage]

Side is not transmitted to the object ball, running side on the cue ball gives a greater margin for success for a cushion shot because it makes the cue ball hug the cushion while the side is taking effect. If the cue ball hits the exact point of BOB and cushion together then the ball is potted. If the cue ball hits just before the cushion and BOB then running side makes it hugs the cushion for a fraction before making contact on BOB and the ball is potted. If the cue ball contacts the object ball at a point other than BOB and cushion together or the cushion too far before the object ball then the running side will have no effect on the pot, the pot will be missed.
Komikano's theory of throw states that side on a cushion shot would be the wrong way to go as running side would throw the object ball into the cushion rather than along it and check side would throw the object ball away from the cushion rather than along it.
Maybe that's why he plays cushion shots plain ball as he believes that "throw" will make the object ball leave the cushion.
Myself I believe that throw of the object ball is just complete bollocks and that komikano is deluded by an effect that he doesn't understand.

High speed video showing proof of spin induced throw:
http://www.youtube.com/watch?v=GpsVeOYGcu8

[nrage]

Full list of High Speed Videos by Dr Dave:
http://billiards.colostate.edu/high_...eos/index.html

Click "Home" to get to the article list, normal speed video, and other resources.

[ace man]

Double. Sorry.

[ace man]

Side is not transmitted to the object ball...

Hmm. Have you tried looking at it from a physics perspective and not as a player? One spinning phenolic sphere hitting another full in the face, both with same mass. The *is* a little bit of friction between two phenolic surfaces, always, even if the balls are cleaned. Some side spin must be transmitted even if the amount is extremely small, so small in fact it is barely noticeable? What would it take for side not to transfer? No friction at all?

This is one of those cases where I'd rather believe a PhD professor than a player, any player, I don't care how well he plays or what billiard game he plays. While a top player might have fabulous skills as far as playing goes, he might not have enough education to really have deep understanding of what really happens when two balls collide. After all he did spend most of his time in a snooker hall, not at college! In fact, a great player would be better off without such information because he doesn't really need it. All he needs is a great feel to play the game well at subconscious level.

[komakino]

Spin does transfer but too little to be of any use apart from in 9 ball due to the Simonis type table cloths.

Spin induced throw is totally different on the other hand and definitely works to different degrees on both surfaces. I often play that shot when I can't quite see the potting angle. People can repeatedly tell me that it's "complete bollox" or doesn't exist but I know differently. I use it to good effect.

@ace man : I actually do have a physics/astrophysics degree, but when playing go completely from gut...although knowledge always helps when position runs slightly off. Saved my ass last night...had to give 45 points handicap start to opponent but rescued a break half way through with a throw shot to continue the break and eventually win the frame.

[calgo54]

hi a small tip is too look at the light on the ball that shows from the lights above if you walk around to the poting angle and point your cue were the poting point is this light should be there thats a way i got shown and it worked for me.

[vmax4steve]

Spin induced throw is totally different on the other hand and definitely works to different degrees on both surfaces. I often play that shot when I can't quite see the potting angle. People can repeatedly tell me that it's "complete bollox" or doesn't exist but I know differently. I use it to good effect.

Please explain to me how spin induced throw works when potting a ball touching the cushion when using running or check side. If the object ball is thrown when the cue ball is spinning then how does the object ball stay tight on the cushion ? According to this throw theory it should either but thrown into the cushion or away from it when hitting the exact point of contact or BOB and surely cannot be thrown onto the correct path when struck at a point other than BOB because the cushion is in the way.

[komakino]

Explanation: When playing with side it is extremely difficult to hit the correct point of contact on the OB as the CB is subjected to deflection/squirt and swerve etc. We all know this hence the difficulty in aiming when playing with side. Experience helps us but it is never an exact science. The adjustment of aim is dependent on lots of factors such as distance between CB and OB, speed of shot, against or with the nap etc etc.

The aiming or shot as a whole may be deemed to be successful by the OB going into the pocket, but it doesn't mean that you've hit the OB exactly where you would if playing without any side.

As a specific example to fit your question, when playing a ball on the cushion with running side, you actually may be slightly overcutting the ball due to cue ball squirt/deflection, but this small effect is cancelled out by the throw.

The reason I don't pot balls along the cushion myself very often with side is because I usually don't want to affect the angle that the CB comes back off the cushion. If I do, then I will use either check or running side no problem...it's just not necessary or needed in order to pot the ball.

[nrage]

Please explain to me how spin induced throw works when potting a ball touching the cushion when using running or check side. If the object ball is thrown when the cue ball is spinning then how does the object ball stay tight on the cushion ? According to this throw theory it should either but thrown into the cushion or away from it when hitting the exact point of contact or BOB and surely cannot be thrown onto the correct path when struck at a point other than BOB because the cushion is in the way.

When a spinning ball hits a cushion it looses some of the spin/rotation as the spin is turned into forward motion in the new direction of travel. That's why running side causes the ball to speed up off the cushion, and check side does the opposite, for a good example of this see:
http://www.youtube.com/user/FargoBil.../5/Oii0UhnYjCc
(from 6:07)

So, less spin means less spin induced throw, in this case I suspect you get none at all given how little side you typically want to put on this sort of shot.

[komakino]

When a spinning ball hits a cushion it looses some of the spin/rotation as the spin is turned into forward motion in the new direction of travel. That's why running side causes the ball to speed up off the cushion, and check side does the opposite, for a good example of this see:
http://www.youtube.com/user/FargoBil.../5/Oii0UhnYjCc
(from 6:07)

So, less spin means less spin induced throw, in this case I suspect you get none at all given how little side you typically want to put on this sort of shot.

I agree to some extent with this too, but side will remain on the CB for easily 2 to 3 or more cushion contacts on a good table before disappearing entirely. I stick by my original explanation to cover the effects observed after the first cushion contact.

[vmax4steve]

As a specific example to fit your question, when playing a ball on the cushion with running side, you actually may be slightly overcutting the ball due to cue ball squirt/deflection, but this small effect is cancelled out by the throw.

You've hit the nail right on the head there m8 as you can slightly overcut the ball when playing with running side as the side then makes the cue ball hug the cushion for a short distance so that it strikes BOB, it also strikes BOB when judged correctly. But your throw theory states that you strike the object ball thicker than required and the throw then sends the object ball onto a different path, so if the cue ball is spinning as it strikes the cushion just before the object ball, and this squirt as you call it, makes the cue ball strike the object ball exactly on BOB, with the cue ball spinning just as it would when playing your throw shot, this is in effect striking the object ball too thick according to your throw theory and the pot should be thrown into the cushion and therefore the pot will be missed.
This is what the video you posted shows, hit the ball too thick and throw makes the object ball take a different path, yet now you're saying that this doesn't happen when the object ball is on the cushion because the effects of running side are cancelled out by the throw, and yet it's supposed to be the spinning cue ball that makes the object ball throw.
According to your throw theory when played with check side you will have to actually have to hit the object ball too thin in order to throw it along the cushion, yet this is impossible because the cushion is in the way and the squirt you get with running side isn't there as the cue ball does not hug the cushion for longer than normal because the check side "checks" the cue balls path off the cushion.

The reason why myself and many other players use running side for pots along the cushion is exactly because of this "squirt" effect, it gives more margin for error as you can strike the cushion either just before or dead on cushion and BOB and still pot it. A plain ball shot can be played but it is not so easy while a check side shot is very difficult as there is no squirt effect and the path of the cue ball must be judged exactly because the object ball

CANNOT BE THROWN BY THE SPINNING CUE BALL BECAUSE THE CUSHION IS IN THE WAY OF THE THINNER CONTACT NEEDED IN ORDER TO ALLEGEDLY THROW IT THE OTHER WAY. THIS IS THE EXACT REASON WHY THESE VIDEOS DO NOT SHOW THIS "THROW" EFFECT WITH BALLS ALONG THE CUSHION, BECAUSE IT IS COMPLETE BOLLOCKS. THE OBJECT BALL IS NOT BEING THROWN, THE CUE BALL IS SWERVING VERY SLIGHTLY AND CONTACTING BOB. THESE VIDEOS ALSO ALWAYS SHOW THIS EFFECT DEMONSTRATED ON A DEAD STRAIGHT CONTACT WHEREAS THIS EFFECT SHOULD ALSO BE POSSIBLE NO MATTER WHERE THE CUE BALL STRIKES THE OBJECT BALL BECAUSE THE POINT OF CONTACT MUST ALWAYS BE THE SAME SIZE SO THIN CUTS CAN BE THROWN AND THICK CUTS CAN BE THROWN BUT THE BALL ALONG THE CUSHION SHOWS THAT THIS CANNOT POSSIBLY HAPPEN, THE BALL ALONG THE CUSHION MUST BE STRUCK AT BOB YET IT STILL POTS WHEN PLAYED WITH SIDE'

[nrage]

Firstly, whether or not spin transfer occurs for a shot along the rail is not evidence for/against it occurring for another type of shot - like the straight shots shown in the videos. I believe the videos, and the detailed physics shown in the articles, are very good evidence that it does occur on straight contacts, but there are several reasons why it might not occur for shots along the rail.

So, here are several (potentially competing) ideas I have had as to what might be going on in a shot along the rail.

1. The force on the BOB at impact is less for a cut shot than a straight shot. This is because force is a vector, so it is greatest for a straight shot and gets less the thinner you go. You can see this in the speed of the white/object on each type of shot. So, if the amount of spin which can be transferred depends on this force, then less force may mean less spin transfer, there may be a minimum required force for any spin transfer and a certain cut angle may effectively never produce spin transfer.

Given that most shots along the rail are played slow, with only a little side, and given they are usually thin contacts, I can see this meaning there is no spin transfer on this type of shot.

2. When the white contacts a cushion it compresses it. This, with running side can actually bring the white in behind the ball/BOB, doing this would normally take the object ball off/away from the cushion, but spin transfer could potentially counter this effect.

Perhaps, when you hit the rail slightly before the correct BOB this is what happens, and spin transfer corrects the path of the object ball. Combine this with idea #1 above, which would imply no spin transfer for hitting BOB exactly and you could explain why adding running side works for rail shots.

3. When the white hits a cushion with side it effectively stops spinning on the spot and start rolling down the cushion (for a microsecond). The cushion is canceling all the in/out forces leaving only the force directly along the cushion. This force is again 'weak' compared to the in/out forces so BOB force is also weak, meaning (perhaps) very little spin transfer.

I think all the ideas above are possible, some more likely than others, and I think they all can explain why you do get spin transfer on straight shots and why it might not occur along the rail.

[komakino]

@nrage

I can see sense in all of those arguments but are you sure you mean to say 'spin transfer' rather then spin induced throw? 2 totally different effects.

spin transfer - spinning CB causing the OB to pick up the opposite spin after contact - very slight on a snooker table IMO
spin induced throw - alteration of the OB leave angle due to a slight push to the left or the right due to grip between a spinning CB and a non-spinning OB - very conspicuous on a snooker table - I use it all of the time when I can't quite see enough of the ball to pot it plain ball.

?

[nrage]

@nrage

I can see sense in all of those arguments but are you sure you mean to say 'spin transfer' rather then spin induced throw? 2 totally different effects.

spin transfer - spinning CB causing the OB to pick up the opposite spin after contact - very slight on a snooker table IMO
spin induced throw - alteration of the OB leave angle due to a slight push to the left or the right due to grip between a spinning CB and a non-spinning OB - very conspicuous on a snooker table - I use it all of the time when I can't quite see enough of the ball to pot it plain ball.

?

Yes, it seems I wrote spin transfer where I meant spin induced throw. The two effects are different, but they are inter-related and usually occur at the same time tho I can see how different cloth, and weight of balls may mean more of one and less of the other.

[komakino]

@nrage

I agree.

Just out of interest, I see that you understand the principle, but do you actually employ the effect in play as I do when necessary?