Rail/Cushion/Pocket Height Problems

[Master Blaster]

A recent new cloth and cushions were fitted to our match table and 18mths later the balls are bouncing out the pockets after hitting the leathers plumb, especially the middles. Balls will also jump up in the air off the cushions and if they hit the knuckles after a firm stun, they can leave the table. The pockets aren't bags, they're cut to a comp size because some of us play county. One theory I have is the rails are too short in height, compared to other tables I look after. Can this be the issue? I'll post a video later to show what I mean. But its like when you put snooker balls on a pool table and they have problems staying on there. If the rails are to low then could the cushions will be as well, as they sit about 1mm before rail height?

I have no idea what cloth was put on as I wasn't there when it was fitted but it's slower than a 4yr old 6811 T at one of my other clubs so I doubt it is pure wool. The table is BBI 4 times a week so it the baize if as smooth and fast as anyone can make it. The cushions are 39mm above the table, is this too low Geoff Large/TD/Deano or any other table fitters/experts?

*In this video I play a stun-run-through with the white just below middle and slightly off the cushion, trying to return to pot the ball in the middle again, so maybe 12ft of travel, not 24ft, so not that hard, but quite firm:

The red bounces out. This table is ruining a lot of big breaks.

HELP!

[jlowap]

I've slowed it down... uploading. Could do with a higher rate video, have you got an iPhone?

It seems to be that the red bounces up off the bed and hits the pocket bag.

https://www.youtube.com/watch?v=tA37a4YbqSI

[Master Blaster]

Thanks James, you're right. I'll have to think about that, it could just be the ball bouncing because of stun, which we've seen on tv tables. I filmed it in HD with my Nokia 1020 but the way youtube encodes and kills mp4 is basically rubbish.

[DeanH]

Yes, the top of the rail/cushion is meant to be 39mm and as you can see from the diagram below, taken from the WS pocket template set, the important metric is the point of contact of 30mm.
I have an idea (could be wrong ) that if the cushion cloth is a bit tight it may pull the rubber and the point of contact down a bit.

Not sure what the bottom diagram depicts and where on the table/cushion this scenario is, anyone?

[Master Blaster]

Thanks bud. Is the bottom one the rubber cut into the pockets Dean? Or are these just 3 different cuts of rubber allowed by WS shown for example?

I'm a bit confused because I thought they always use Hainsworth Northern Rubber?

[DeanH]

Rail/Cushion/Pocket Height Problems

you be right that the three are the progress into the pocket and the bottom one is the profile at the further point in the pocket where the rubber has stopped. not sure

[Master Blaster]

you be right that the three are the progress into the pocket and the bottom one is the profile at the further point in the pocket where the rubber has stopped. not sure

You be learnin' me with all your readin' an all!

So the middle pic is the apex of the bumper? I guess if it was square the knuckle wouldn't take the ball in? On the match table in my post, the black ball won't go in to the bottom pocket unless plumb, not even at drop pace. So I'm now thinking, has the rubber around the knuckles been cut properly or left with too square a face (pic 1). I will have to check the shape under the cloth now as my next question.

[DeanH]

Rail/Cushion/Pocket Height Problems

my previous post should have started "you may be..."
the thing with the WS and ISBF pocket images etc is that often they don't have the full information; like for these images they should have above elevation diagram showing the placement of these profiles

[Master Blaster]

my previous post shouldhave started "you may be..."
the thing with the WS and ISBF pocket images etc is that often they don't have the full information; like for these images they should have above elevation diagram showing the placement of these profiles

True, but I've seen fitters in action around pockets and one will use a stanley knife to cut the undercut after he's fixed the rubber on to the block. Obviously, if he left it square, snooker would be extremely difficult not just difficult because the pockets would be ultra tight and everything would bounce out anyway. So what you've explained makes logical sense to me. If I find a square face on the knuckle apex I will have found the answer I reckon.

[DeanH]

Rail/Cushion/Pocket Height Problems

could be the case
check the height of the contact point as well
let us know what you find

we have one table where the top and bottom rail that bounce the ball on contact in place, I have been meaning to check the contact point height
could be where people have sat on the rail and pushed the rubber lower ?

[Master Blaster]

Now I remember it, when the table was done (new cloth/rubber) the teams wanted tighter pockets. The fitter didn't introduce new rails/blocks but left more rubber on going into the pockets to close the gap, so there is definitely less undercut than before the new rubber. If he's left it more square, that could be why the balls are pinging out. The rubber will be the wrong shape, there will be too much of it and too much energy is being returned = ping out. Holy crapola, that's the worst of both worlds! Honest, it's like trying to pot the black on a Star, worse in some ways.

We had a table where you couldn't pot down the the two pink rails but that was because the black rail rubber was old and dead. This rubber is still lively.

Yes mate, I've taken a pic on my phone so I'll carry the pic and a ruler to check the contact point and feel the knuckle shape at the apex with my hand. If the theory turns out to be true, we are ******. The only solution would be new rails, blocks and more rubber and it would be cheaper and better to buy another table I think.

Cheers Sherlock!

[DeanH]

Rail/Cushion/Pocket Height Problems

pocket profile is a minefield mate
in the diagram set from WS/IBSF there is a diagram the shows the slate fall differences, and all it shows is four(?) different coloured lines - no key as to which colour is which organization and no dimensions

[Master Blaster]

pocket profile is a minefield mate
in the diagram set from WS/IBSF there is a diagram the shows the slate fall differences, and all it shows is four(?) different coloured lines - no key as to which colour is which organization and no dimensions

I think WP make it up as they go along. Does anyone know the official minimum pocket gap on a Star table for WS events?

[DeanH]

here is the World Snooker template diagram which the block templates at the events should follow when fitting the tables

[Geoff Large]

The old way of undercut was to file away the rubber under the nose of the angle until it was almost a sharp angle

the modern and now the correct way , and you can see this on match tables on TV is to leave a square face almost like the face of the cushion going right around the angle and into the back of the radius , they have been doing this for over 10 years now look back on youtube at some old footage of TV tables and you may find the period they changed it , I think it was the mid 1990s

look at my two examples in the link below of a proper finished smooth undercut and a rough speed fitters attempt

I think it is not that the nose is now square going into the angle and all the way to the rear , but the rough undercut that may be your problem ?

having studied your shot of the ball on the video link , the ball is already bouncing before it is anywhere near the pocket so is off the bed as it hits the pocket therefore it will bounce up more into the air as it rebounds as the centre of the ball is way above the nose of the lower angle of the flat edge , making the ball lift rather than be seated to the bed on the rebound .
place the ball against the cushion , the ball should be slightly under the nose , so imagine a centre line on the ball , it should be under the lower edge of the nose of the rubber .

if a rubber is too high the ball tends to die a bit , if it is level or below level the ball tends to jump , there is a fine line where you get maximum bounce from the cushions before it begins to jump , I always buy wood blocks from peradon they are made to the exact height for rubber
so no problems when fitting and shaping for rubber .

some fitters insist on making their own blocks unless they make them correct there will be problems , if oversized blocks are fitted then it is a full strip down and fit new blocks or plane old blocks down to correct height and refasten back on , this may also result in another Re-rubber , I have come across this twice recently and I have told the fitter concerned that he would be better off using Peradon standard blocks when re-blocking and re-rubbering . rather than make his own , but he is set in his ways .

http://gclbilliards.com/a-couple-of-...-rubber-angle/

and also http://gclbilliards.com/plenty-of-re...april-and-may/