Mirror Banking Tool Question...

[Runnin8]

AZers,

I am playing on a bar team where I get called on alot to coach during a match. Often it involves kicking or banking out of trouble. I have created this diagram to use as a tool to help my team mates visualize the kick/bank. During a match we'd layout the key balls on the center table, mirror as appropriate, and then show the aim line relative to the diamonds so it's something concrete.

A couple of questions: 1) do you think inexperienced players will grasp the concept quickly? 2) Can they be successful with center ball, medium hit, single rail kicks using a tool like this? and 3) Is it laid out correctly ?(created for a 44 x 88 table- I'll have to adjust for 39 x 78 bar box. The tables are overlapped by the width of a ball)

Thanks,
Steve

 

[ez2h8]

I think it's a good idea. I am not sure if you will have enough time during a match or time out to use it everytime but as a learning tool or discussion tool after the match or while the opponent shoots, sure.

I have not seen something like this used, mostly the captain and the player seeking advice discuss the shot over the table and point where and how to hit the ball. Doesn't hurt to try and nice job

ez

 

[teebee]

This is as good a diagram as I have seen to illustrate the mriror system. I understand the diagram and the idea behind it but must lack some visualisation skill required to make it work.
I have had to use other methods that require less imagination. I think many players especially new players may be like me. Have you read "Banking With The Beard". There is some amasing information there. I doubled (at least!) my chances of making simple banks shortly after practicing some of the shots he teaches.

 

[Bob Jewett]

... A couple of questions: 1) do you think inexperienced players will grasp the concept quickly? 2) Can they be successful with center ball, medium hit, single rail kicks using a tool like this? and 3) Is it laid out correctly ?(created for a 44 x 88 table- I'll have to adjust for 39 x 78 bar box. The tables are overlapped by the width of a ball) ...

Quickly? Many players have a hard time with formulas like doubling the diamond for a mirror bank. Figure a quarter of an hour of discussion with examples before a player can use it on his own. I think that teaching them the "doubling the diamond" method will be more useful.

The mirror system (any way you want to calculate it, including with your diagram) is not accurate unless you also are careful about the spin the cue ball has when it gets to the cushion. Most beginners will have a problem with that.

I assume you mean that the rail grooves of the adjacent tables are coincident. If so, the layout is geometrically correct.

 

[HittMan]

"Mirror Image" advice

I think your geometry is correct so that will not be a problem.

The problem comes at the visualized point, it is important to encourage players to attempt to visualize the entire ball or pocket instead of a point in space (balls are not points). This requires practice and the ability to adjust based on results because not all tables/rails are square/parallel/perpendicular (like they will be in heaven, I'm sure).

Spin will be a problem as well but spin will be a problem on all banks regardless of method.

When I coach, I do the visualization and indicate the point on the rail to hit with whatever spin.

Mirror image is an intuitive tool in my opinion and works on all tables for single rail shots...gets a little dicey on multiple rail shots because of the sppin the ball picks up off the first rail.

I use it successfully and believe you can as well.

Just my opinion...you be the judge.

Hittman

 

[Patrick Johnson]

I think that teaching them the "doubling the diamond" method will be more useful.

Sure, since it can be carried in the head, and I think the diagram is a good visual aid for graphically showing how doubling diamonds = mirror angles. It may be especially helpful for players who have difficulty understanding doubling diamonds.

The mirror system (any way you want to calculate it, including with your diagram) is not accurate unless you also are careful about the spin the cue ball has when it gets to the cushion. Most beginners will have a problem with that.

Conveniently, most beginners' inaccuracy far outweighs such refinements so they can afford to take a little time to absorb them as they gain the skill to use them.

I assume you mean that the rail grooves of the adjacent tables are coincident. If so, the layout is geometrically correct.

To be really accurate I'd add, say, 1/2 inch per side to account for lateral travel while in contact with the cushion. As balls roll along the cushion while compressing and uncompressing it, they follow a curved path that "cuts the corner" of the effective rebound angle, so its point is a little beyond where the ball reaches.

pj
chgo

 

[duker]

mirror banking

I remember maybe 5-6 years ago, someone at Valley Forge were selling mirror sets that go under the rails in order to help learn banking. I think they retailed for $75.00, but I can't remember who it was, someone here might have that information for you.

 

[Jal]

...To be really accurate I'd add, say, 1/2 inch per side to account for lateral travel while in contact with the cushion. As balls roll along the cushion while compressing and uncompressing it, they follow a curved path that "cuts the corner" of the effective rebound angle, so its point is a little beyond where the ball reaches.

On the other hand, since the mirror system assumes angle out = angle in, to achieve this the cueball has to pick up topspin on the way to the first cushion and it has to retain some of this after contact with it (otherwise cushion friction will shorten the reflection angle). It will then masse to equalize the angles (out = in), thus tending to pull" the effective reflection plane away from the rail gutter/grove.

It's not an easy thing to figure out exactly where the plane should be located - it depends on speed and incident angle as well as the amount of topspin. There is no single fixed position. But balancing your observation (lateral travel during contact) with the above consideration, using the rail gutter is probably a good enough guess for many situations, which is what the original poster uses in the diagram.

Jim

 

[Runnin8]

Thanks for the comments...

I appreciate the guidance! Our league is really very friendly to coaching and I know that we have even allowed multiple timeouts during the same game with no imposed time limit; the only rule is that the coach can't touch the table or balls. I plan to have a handful of these printed out and on a clip board just in case. Most of the use will be in kicking out of a safe where the ball is away from a bank- cases that make doubling the diamonds harder I think. As an example, I figure we'll wind up with something like this on the page after a time out:

As we have more opportunities to practice I hope to share, and continue to learn, how to correct for the inadequacies of the method. I joined the team before learning that they were in last place and we have since climbed up 3 spots. My last session with one team mate was teaching him how to hit a stop shot. I'm enjoying the teaching aspects to the game and will consider the season a win if any of them improve their confidence in the game.

Thanks guys!

Steve

 

[Patrick Johnson]

On the other hand, since the mirror system assumes angle out = angle in, to achieve this the cueball has to pick up topspin on the way to the first cushion and it has to retain some of this after contact with it (otherwise cushion friction will shorten the reflection angle). It will then masse to equalize the angles (out = in), thus tending to pull" the effective reflection plane away from the rail gutter/grove.

It's not an easy thing to figure out exactly where the plane should be located - it depends on speed and incident angle as well as the amount of topspin. There is no single fixed position. But balancing your observation (lateral travel during contact) with the above consideration, using the rail gutter is probably a good enough guess for many situations, which is what the original poster uses in the diagram.

Jim

The diagram is for showing simple mirror angles unaffected by ball/cloth friction. Ball/cloth friction, including the kind you mention, is the effect that changes the simple mirror angles and that must be controlled by controlling CB rotation or by adjusting aim. It would be counterproductive to adjust the diagram itself to include any of the ball/cloth friction effects, because (1) choosing which one to include is arbitrary and (2) then the "natural" angles aren't clearly shown and learning to identify and compensate for the friction effects is made much more difficult.

pj
chgo

 

[Bob Jewett]

I remember maybe 5-6 years ago, someone at Valley Forge were selling mirror sets that go under the rails in order to help learn banking. I think they retailed for $75.00, but I can't remember who it was, someone here might have that information for you.

I saw one version of these. The problem is that they are in the wrong place for the geometry. Also, if you bank hard, you hit the mirror.

 

[Jal]

The diagram is for showing simple mirror angles unaffected by ball/cloth friction. Ball/cloth friction, including the kind you mention, is the effect that changes the simple mirror angles and that must be controlled by controlling CB rotation or by adjusting aim. It would be counterproductive to adjust the diagram itself to include any of the ball/cloth friction effects, because (1) choosing which one to include is arbitrary and (2) then the "natural" angles aren't clearly shown and learning to identify and compensate for the friction effects is made much more difficult.

pj
chgo

Yes, keeping the diagram as simple as possible is important. But you suggested a refinement for the location of the reflection plane based on the ball's movement parallel to the cushion during contact with it. While it's certainly valid, I think you have to consider other things when you start making such refinements.

The rebound angle "naturally" comes up shorter than the incident angle without some compensatory spin. If you use sidespin to equalize them, the effective reflection plane moves toward the cushion instead of being fixed at the rail gutter, and this adds to the effect you described. But topspin has the opposite effect and moves the reflection plane away from the cushion. Happily, this counters the parallel travel effect (during contact) and at least makes the rail gutter a decent candidate for it's location.

When using sidespin to equalize the angles, using the nose of the cushion is a better guess.

Jim

P.S. For those unfamiliar, the rail gutter is 1/2 ball width toward the center of the table from the nose of the cushion.