Cushions increasing ball speed

pt109

WO double hemlock
Silver Member
Thanx Doc

Good answers. I can think of many more along these lines, but they are also silly.

Another possibility is if the cushion could somehow convert the rotation of the ball into stored energy that could somehow be returned to the ball as translational energy, but I can't imagine any way this could be possible with regulation pool equipment.

Again, I think this video explains and demonstrates the physics quite well:

The CB looses quite a bit of speed off a rail, even with slick conditions.

Regards,
Dave
As usual, watching you videos is time well spent.
I think most modern rails are too low.In the Theory of the Ball (written
in the late 1800's)it says the rail height should be about 70% of the
ball's height.At a lower height the ball goes air-born.At a greater height
the ball is pinched and bounces air-born.
An old Brunswick owned by Frank Taberski had higher rails and played
great.I feel the lower rails are to accomodate the average player who
can't shoot a frozen cue ball without miscueing.

8pack

They call me 2 county !
Silver Member
I'll give you infinite odds: I'll put up 20 if you win, you put up 0 if you lose.

I agree with you I've played on some GC's with messed up rails that look like the ball was coming out faster than it was going it. But I think what is going on is it is so different than what we expect on normal rails, that our mind thinks its faster on the way out then on the way in.

I don't want to bet too much, because I can see this turning into a proof argument that will end up being a whole bunch of hassle for everyone involved.[/QUOT
----------------------------------------------------------------------------------------------------------------------
I will try to get a video on here this week and just let everyone decide for
themself.I have played on alot of different table where ball seems to speed
up after hitting the cushion but this table beats them all.Am i 100 percent sure
that it is speeding up ,no,but its got us all saying it is thats played on this table.
Dont take the betting thing to serious,i was just kinda funning around and
dont mind making small wagers now and then....Two the eye i think i would
win but a radar gun not sure.

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CreeDo

Fargo Rating 597
Silver Member
One way you could get a deceptive effect is if you hit just a little low on the CB (maybe even intending to hit center). It hits the rail with some backspin but because the ball is rapidly sliding and the hit wasn't way below center, the human eye doesn't see it. It then backspins off the rail to get a little extra kick.

Bob Jewett

AZB Osmium Member
Staff member
Gold Member
Silver Member
Players at my local pool hall seem convinced that a Diamond bar table they use increases the speed of the ball after rebounding off the cushion.

Obviously you can stun a shot with spin and make it speed up off a rail, but can a center english shot actually gain speed after contacting a rail?

I find it hard to believe...where does the extra energy come from? They seem to think the cushions can add energy. I think only transferring spin to linear movement can do this. Especially if a ball hits a rail with any kind of forward spin.

Paging Dr Dave and Mr Jewett....
When a ball goes straight into the typical rail, it loses about 50% of its speed and 75% of its energy. That's the total loss due to the deadness of the typical rail, and the fact that the ball loses speed in going to smooth rolling in its new direction. That's shown very clearly in Dr. Dave's video.

Some rails are not as dead as others, so they do add speed, but only in relation to another rail. If a cushion returns 70% of the stored energy rather than a typical 50% it will look like it's adding speed, but of course it's not.

I played on a table that you could easily get six table widths when shooting across the table with moderate speed. The cushions were sticky and mounted low.

One problem with the bar table comparison is that most bar tables have cushions that seem to be made from ground up bicycle tires and sand. Going to a table with real rubber cushions will be a strange experience for players used to junk.

Tramp Steamer

One Pocket enthusiast.
Silver Member
I am going to side with the impossible group on this one, even though my eyes have told me different at times. Reminds me of this one road you can drive on around here and you would swear you were driving up hill, but your really going down. You cant always trust what you see.

And that is precisely why I've been married three times.

bud green

Dolley and Django
Silver Member
Thanks for the replies.

I actually only started this thread because they obviously didn't seem convinced it was impossible.

Bob and Dave rule...I figured they would of already done some tests and if my friends don't want to believe me, they'll probably believe them.

mbvl

AzB Silver Member
Silver Member
In a recent article in one of the pool magazines the writer stated, "When you cut the first ball thin, the cue ball speeds up after contact".

Add these two "facts" together and you can get some amazing results.

Mark

8pack

They call me 2 county !
Silver Member
After watching this video i dont think the ball is picking up speed but i cant tell.But when your there and your watching it ,it looks a whole lot different.

(Watch when it hits the rail)

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realkingcobra

Well-known member
Silver Member
Players at my local pool hall seem convinced that a Diamond bar table they use increases the speed of the ball after rebounding off the cushion.

Obviously you can stun a shot with spin and make it speed up off a rail, but can a center english shot actually gain speed after contacting a rail?

I find it hard to believe...where does the extra energy come from? They seem to think the cushions can add energy. I think only transferring spin to linear movement can do this. Especially if a ball hits a rail with any kind of forward spin.

Paging Dr Dave and Mr Jewett....

I think I asked once already, but where is this table located?

Glen

Silver Member

dr_dave

Instructional Author
Gold Member
Silver Member
OK ...

The cue ball can't gain speed off a rail, even with bouncy and slick conditions.

Is that simple enough? :wink:

Regards,
Dave

realkingcobra

Well-known member
Silver Member
OK ...

The cue ball can't gain speed off a rail, even with bouncy and slick conditions.

Is that simple enough? :wink:

Regards,
Dave

Dave, having been a table mechanic for over 26 years, I'm aware of that, as I also posted the same answer in the thread as you did. WHY I want to know where this Diamond is located, is so that if I can schedule stopping by the location and change the way the table plays...for the better.:grin:

Glen

realkingcobra

Well-known member
Silver Member
OK ...

The cue ball can't gain speed off a rail, even with bouncy and slick conditions.

Is that simple enough? :wink:

Regards,
Dave

Had you read my posts in this thread I think you'd have asked my "why" I wanted to know where the table is located....instead of the sarcastic answer you posted....as I am not new to how tables play...or why:grin: so your apology IS accepted...OK?

Neil

AzB Silver Member
Silver Member
After watching this video i dont think the ball is picking up speed but i cant tell.But when your there and your watching it ,it looks a whole lot different.

(Watch when it hits the rail)

I have to agree with the science guys that it is loosing speed. But, I also agree with you that it LOOKS like it's gaining speed. I've seen tables like that before, and they drive me nuts. Makes playing position a real challenge. It's like starting all over again.

cleary

Honestly, I'm a liar.
Silver Member
It's physically impossible for a ball to come off a rail faster than when it hits.

Unless you're using running english.

SlimShafty

AzB Silver Member
Silver Member
Can you imagine if this was possible, you hit the side rail, ball picks up speed and hits opposite side rail picks up more speed, the ball would continue to pick up speed, and well it would be some sight.

We would all have Diamond tables powering our houses...LOL

realkingcobra

Well-known member
Silver Member
Alright...does ANYONE else know where this Diamond table is located that Bud Green was talking about in this thread??????????????

I'm beginning to wonder if this table even exists, seems no one knows anything about this table....and Bud won't respond to my PM's or here in his own thread!

Glen

Neil

AzB Silver Member
Silver Member
Alright...does ANYONE else know where this Diamond table is located that Bud Green was talking about in this thread??????????????

I'm beginning to wonder if this table even exists, seems no one knows anything about this table....and Bud won't respond to my PM's or here in his own thread!

Glen

His last activity was at 8:52 am. He probably hasn't been able to get back on line yet today. Give him some time, he'll get back and respond.

8pack

They call me 2 county !
Silver Member
I have to agree with the science guys that it is loosing speed. But, I also agree with you that it LOOKS like it's gaining speed. I've seen tables like that before, and they drive me nuts. Makes playing position a real challenge. It's like starting all over again.

Its funny to watch peoples expressions when its there first time on the table.

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realkingcobra

Well-known member
Silver Member
His last activity was at 8:52 am. He probably hasn't been able to get back on line yet today. Give him some time, he'll get back and respond.

Alllllright, we're getting somewhere...thank you Neil, I've asked him before the same question....I just want to see if I have the time to sidetrack my trip back to the Diamond factory from Washington State...by way of California:grin: and stop in and change the way this table plays...then sit back and see what everyone thinks about the change in the play...and I'll even use the same cushions over again on the same table just so that nothing is replaced...except the cloth of course:grin:

Glen

PS. I'm not even interested in charging the location owner for changing the way the table plays.