Big bounces off the cushions?

[DeanH]

Hi Terry
Kicks - was it not you (IIRC) that tested your sets of balls by rubbing a set in your hands before play and noticed a reduction of kicks compared to the un-molested set?

[Terry Davidson]

DeanH:

I've found cleaning the balls with my bare hands definitely cut down on the number of kicks I was getting but it didn't eliminate them. When I put the nearly-new #10 on my table and got a brand new set of 1G balls I found I was getting a lot of kicks and I did reduce them but this could also be a case of the balls being worn in a bit and also the cloth getting a little worn in.

I am still getting kicks, especially off the black and pink spots as they are the most used although I've found if I brush up the nap on the spots (I use a small brass brush that looks like a toothbrush) and then using the same brush lay it down again this has also almost eliminated the kicks off those spots.

Terry

[DeanH]

When I had the new set of TCs, I noticed a lot of kicks from them compared to the old set of balls (make unknown but old) we were using up till then.
But over time (months) the number of kicks has dropped to negligable.
Maybe on the TV, they are always using new/near-new sets of balls hence the frequency of kicks?

[moglet]

Terry,

I had expected Steve Davis and John Parrott to show the same test done without chalk but using a "sterile", a normally handled and a wax polished ball, either the same ball or three separate ones. The results are quite dramatic.

[itsnoteasy]

DeanH:

I've found cleaning the balls with my bare hands definitely cut down on the number of kicks I was getting but it didn't eliminate them. When I put the nearly-new #10 on my table and got a brand new set of 1G balls I found I was getting a lot of kicks and I did reduce them but this could also be a case of the balls being worn in a bit and also the cloth getting a little worn in.

I am still getting kicks, especially off the black and pink spots as they are the most used although I've found if I brush up the nap on the spots (I use a small brass brush that looks like a toothbrush) and then using the same brush lay it down again this has also almost eliminated the kicks off those spots.

Terry

Terry i wonder if you get kicks off the spots as the cloth gets squeezed under the ball causing two things , one, a small dint in the cloth causing a slight jump on the ball to get out the dip,(object ball kick) and two, because the pink or colour is sitting in a slight dint, the the white and pink on contact will not be level(the white slightly higher) and will be hitting each other off perfect center, ( causing the white jump kick?)

[Terry Davidson]

I guess I didn't state it clearly enough. The spots on any table after a bit of use will develop a depression and this will mean the two balls are not making contact on the exact waistline of the balls. To get rid of (or at least minimize) this slight dent in the cloth I brush the nap backwards with my small brass brush and then using the same brush do it with the nap to lay it down again.

I just did this the other day as I was getting quite a few kicks, especially from the pink spot and this treatment eliminated them but as I pot more balls off the spots I know I will have to repeat the treatment as a small depression will always form from the contact between the two balls. You can also see this happening right where the cueball bottom sits when it contacts the black or pink and there will be a wear spot (with probably some chalk too) one ball width from the spot and inline with the pocket.

I have never seen the 'stimp meter' test done using balls treated differently, just the one with chalk on the cushion face.

I agree that the pros get more kicks than club players probably due to them using brand new balls and cloth for every tournament.

Wouldn't you think the ball manufacturer and the cloth manufacturers could get together to finally eliminate kicks? It might be difficult for chalk reasons but at least it might eliminate those kicks the pros get on new cloths using the new balls (even after the ref cleans the balls). I suspect these are from both static electricity and also the lubricating oil used by the cloth manufacturer when they shave the nap during the final production process. The oil causes a difference in static potential on the face of the object ball.

Does anyone know if kicks are less prevalent with Hainsworth cloth?

Terry

[Achamian]

Terry, I've posted a thread about my experiments with 'kicks' here.

http://www.thesnookerforum.co.uk/boa...lem-The-answer!

From reading your various posts, I can see that you obviously know an enormous amount about all aspects of snooker. So any comments from you in that thread will be most welcome and greatly appreciated. :snooker:

[magicman]

I think big bounces are caused as much by a trace of unwanted side adding a little speed as much as anything else. I was unaware of the Davis experiment referred to by Terry, and if that's true then a quick wipe of the cushions after every frame as a matter of course should help eradicate this problem.

Kicks are a different matter. I think it's a variety of different causes tbh. Some are caused by poor cueing and are revealed to be so by slow motion replays which show the ball bouncing before contact. Some are caused, aka like Terry's, by a slight miss-match in height, either on the spots, ball sitting in a finger mark, or elevated sitting on a bed of chalk maybe? Sometimes the cue-ball travels the length of the table smoothly on the baize bed and then kicks on contact, which could still be a height difference or maybe the usual suspect of Keyser Soze, sorry, chalk dust.

[vmax4steve]

Quite frankly I don't believe in big bounces.

You never see a player complain of a big bounce when the shot is played at pace, like a shot to nothing long pot, only when trying for exact position when in close and the shot is played too hard and runs on a bit further than wanted.

[RGCirencester]

I think you can see on the replays that the ball appears to rebound off the cushion unusually quickly sometimes.
I have also seen the Chalk experiment done on the bbc on a separate occasion years ago but this was very unscientific just passing the shots at similar pace.
The ball did appear to rebound quicker with a little chalk on the cushion

[golferson123]

big bounces, physics dictate you cannot get anything for nothing,the ball cannot come of the cush faster than it hits it.but the cushion rubbers could possibly be pre-loaded but this effect would fast diminish over time.

[roykay]

Obviously a ball can't leave the cushion faster than it arrives on it but it does sometimes come off faster than expected.
It has been known for some time that chalk at the point of contact with the cushion causes about a twenty five per cent increase in speed.
The chalk does not have to be on the cushion, it could be on the ball at the point of contact.

Roy

[MasterBreak147]

I have seen on club tables in the past that a certain part of a single cushion used to kick off faster than the rest, thats not a BIG bounce but a true bounce its just the rest of the cushion was worn or sat on at some point etc making it less speedy so it looks like you have a so called big bounce.

isn't this referred to as inconsistent bounce ?

[Terry Davidson]

I have a theory regarding the seemingly big bounces off cushions, at least for the pros on TV. I don't think anyone is saying they bounce off more quickly than they came onto the cushion however sometimes they do seem to get more distance than you would normally expect.

Remember, the pros always play on tables that have just been re-clothed. When a fitter does the cushions he tends to pull the cloth tight and then tack it every 4" to 6" and what I believe is happening is the tight cushion cloth is very slightly pulling down the face of the cushion, perhaps 1/64" or so and when the ball hits this spot directly above a tack the cloth will be pushed in slightly and this allows the cushion face to spring up that 1/64" and this might add just a bit of acceleration to the bounce and this is only going to happen where the cloth is a touch tighter above a tack.

I don't think this will happen on other areas of the cushion and also this effect will disappear after the cushion has been in use for a little while, although in most tournaments the tables are re-clothed a couple of times during the tournament so the chances of bigger bounces are always there.

Just a theory, although I have seen tables re-clothed where you can see where the face of the cushion has been pulled down opposite the tacks (or staples as they use here) but after awhile in use the cloth will loosen a bit and this effect disappears. I would assume the fitters doing the pro tables will do a much better job but perhaps there is still a little distortion on the cushion faces.

Terry

[pottr]

I have seen on club tables in the past that a certain part of a single cushion used to kick off faster than the rest, thats not a BIG bounce but a true bounce its just the rest of the cushion was worn or sat on at some point etc making it less speedy so it looks like you have a so called big bounce.

isn't this referred to as inconsistent bounce ?

I'd go with that.