more squirt for harder shots? -Miz cue from Hell

[mikepage]

I've had the sense that cues squirt more at higher speeds, though I haven't really measured the effect in any controlled way. The problem of course is that when you hit at higher speeds there's less swerve, and this gives the appearance of more squirt. Another problem is accuracy suffers at higher speeds, at least for some of us.

So to make squirt a bigger effect compared to swerve, I constructed the MIZ CUE FROM HELL. I thought about doing surgery on my Scruggs, Josey, etc. but then decided maybe it'd be better to choose the cue from my MIZ collection.

It looks like a normal cue, but suffice it to say proponents of backhand english--the kind where you just pivot about your normal bridge--would be scratching their head with one hand and their butt with the other after a few shots with the MIZ CUE FROM HELL. It has a pivot point of about 7 or 8 inches.

I don't really have results yet, but the exit polls are suggesting I might have been wrong about harder shots squirting more.

mike page
fargo

 

[Colin Colenso]

How are you controlling consistancy of hit?

If you're doing it by trying to hit the same place on the CB yourself ther may be a tendency to subconsciously bring the cue in closer to center ball when whacking it hard.

Just like how guys lift the tip up on draw shots for fear of jumping the CB.

 

[Jaden]

we seem ot think a lot alike.

How are you controlling consistancy of hit?

If you're doing it by trying to hit the same place on the CB yourself ther may be a tendency to subconsciously bring the cue in closer to center ball when whacking it hard.

Just like how guys lift the tip up on draw shots for fear of jumping the CB.

Hey Colin, it seems we must be right on some things because we both seem to be saying a lot of the same things. Like the tendency to bring the stroke back to center on harder shots or when you're using extreme english.

 

[Cornerman]

I don't really have results yet, but the exit polls are suggesting I might have been wrong about harder shots squirting more.

mike page
fargo

Diggers Union got to you, eh?

Fred <~~~ those heavy-handed bastards

 

[Jaden]

I bet that damn Digger's union....

Diggers Union got to you, eh?

Fred <~~~ those heavy-handed bastards

I bet that damn Digger's union is involved with the mafia with the pull they have around here, they just say something and it's accepted on principle and fear. LOL

 

[Colin Colenso]

Hey Colin, it seems we must be right on some things because we both seem to be saying a lot of the same things. Like the tendency to bring the stroke back to center on harder shots or when you're using extreme english.

Well it's always good to find someone who's on the same page

But having witnessed idiots agreeing with each other on occassion, we better refrain from hubristic celebrations just for the moment

 

[Colin Colenso]

A testing method for Mike:

You can set up two rests so that the cue can slide along an identical line and height for various tests. Mark the rest positions where they touch the table/s. You might need a bench set up behind the table.

Place the CB on a piece of paper with a small hole to mark and hold the CB in an identical position.

Slide the cue at various speeds.

For the power shots, take out a baseball bat and whack the butt of the cue. Make sure to use one of those crap cues with an ivory butt cap!

Check where the various speeds hit the end rail. Compare. Repeat, and serve with parsley and beer.

 

[Jal]

....I don't really have results yet, but the exit polls are suggesting I might have been wrong about harder shots squirting more....

Unless some compensatory mechanism is at work, I think that the harder shots should produce at least a little more squirt. The harder the shot, the farther the tip will roll along the surface as the ball picks up rotation, since a harder hit produces more spin and the contact time remains nearly the same. This increases the average offset of the tip during impact, which further increases the final rate of spin.

So a harder shot begun at the same tip offset, will end up producing more "excess" spin than a softer one, and thus more squirt, according to the momentum conservation model. There might be some additional effects from Colin Colenso's surface property idea.

I'm sure you're aware of this as I think you understand the physics better than I do, but I just thought I'd mention it. Maybe the effect is very small.

Thanks for taking the time to actually check this out. Some of us will be very interested in your results.

Jim

 

[mikepage]

How are you controlling consistancy of hit?

If you're doing it by trying to hit the same place on the CB yourself ther may be a tendency to subconsciously bring the cue in closer to center ball when whacking it hard.

[...].

I probably do have that tendency. However, one advantage of the aim&pivot squirt test is it doesn't matter how much english you actually put on the ball. If you're pivoting about a point in front of the "pivot point," left english will send the cueball to the left side of the object ball. And if you're pivoting about a point behind (longer than) the cue's pivot point, then left english will send the cueball to the right side of the object ball.

Other squirt tests, such as seeing how far the cueball squirts over the length of the table *do* depend on getting maximum english, or at least consistent english. So these tests are not as good, imo.

I've tried them both. In the latter case I used a striped ball and checked the location of the chalkmark. In either case I cannot get my MIZ FROM HELL to squirt measurably more at higher speeds. I can get it to squirt a half a diamond over the length of the table. This is not to say *all* cues don't squirt more at higher speeds. But it leaves me skeptical. I think this may be one of those things that seems true for a number of reasons but isn't.

Aiming the "impossible cut shot" is mind boggling with the MFH.

I also tried putting together a rig like you suggested. I wasn't very satisfied, though I was able to send the cueball *and* the cue stick flying down the table with a blow from a mallet... ;-}

The MFH is almost like the cue equivalent of the trick cueball. I think I may take it down to the poolhall and tell the local short stop I'll play him a set straight up provided he uses this p-o-s cue, and then hand him the MFH. It's got a decent tip and it looks solid enough. I think he'll go for it.

mike page
fargo

 

[mikepage]

Unless some compensatory mechanism is at work, I think that the harder shots should produce at least a little more squirt. The harder the shot, the farther the tip will roll along the surface as the ball picks up rotation, since a harder hit produces more spin and the contact time remains nearly the same. This increases the average offset of the tip during impact, which further increases the final rate of spin.

So a harder shot begun at the same tip offset, will end up producing more "excess" spin than a softer one, and thus more squirt, according to the momentum conservation model. There might be some additional effects from Colin Colenso's surface property idea.

A mitigating factor is that the contact time is not really independent of speed; it actually gets a little shorter at faster speeds. And this would tend to (at least partially) cancel the effect you're describing. Also your mechanism predicts both more squirt and more spin for a softer tip, which has a longer contact time. I haven't been able to measure a difference in squirt with tip hardness, so imo, such an effect is at best small.

I haven't looked carefully at Colin's stuff, but at first blush it looks similar to the old "minor miscue" ideas about squirt. The problem with the "little bit of slipping before the grip sets in" idea is that it predicts much more squirt for a heavily chalked tip than a thinly chalked tip. I haven't observed that, and I haven't seen anyone else claim they have.

Another comment I have--really a semantic one-- is that the "momentum conservation model" is not really a base model that can have other effects added onto it. The "momentum conservation model" is complete and unrefutable, unless of course you want to claim momentum is not conserved. As long as Steve Hegg doesn't show up, I suspect nobody's going to make that claim. The model that *can* be incomplete and/or inadequate is the "fixed endmass model." All postulated mechanisms that suggest squirt does or doesn't depend on whatever are equivalent to suggesting the effective endmass does or doesn't depend on whatever.

mike page
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[pete lafond]

I've had the sense that cues squirt more at higher speeds, though I haven't really measured the effect in any controlled way. The problem of course is that when you hit at higher speeds there's less swerve, and this gives the appearance of more squirt. Another problem is accuracy suffers at higher speeds, at least for some of us.

So to make squirt a bigger effect compared to swerve, I constructed the MIZ CUE FROM HELL. I thought about doing surgery on my Scruggs, Josey, etc. but then decided maybe it'd be better to choose the cue from my MIZ collection.

It looks like a normal cue, but suffice it to say proponents of backhand english--the kind where you just pivot about your normal bridge--would be scratching their head with one hand and their butt with the other after a few shots with the MIZ CUE FROM HELL. It has a pivot point of about 7 or 8 inches.

I don't really have results yet, but the exit polls are suggesting I might have been wrong about harder shots squirting more.

mike page
fargo

You will get more squirt the harder you hit, this has been known for quite some time. So you are right. The other side to squirt is your q shaft and how much flex. I do not know how to determine the effects, but I do know that I always seem to mentally adjust without problems. I sometimes leave my cue at home because I did not plan on playing. In which case I use either a house cue or just someones break cue so I do know an adjustment is made. House cues are somewhat stiffer and I do get more squirt cause my adjustment is always bigger.

 

[Jal]

.... Also your mechanism predicts both more squirt and more spin for a softer tip, which has a longer contact time. I haven't been able to measure a difference in squirt with tip hardness, so imo, such an effect is at best small.

It's not clear to me that this is true, but it's probably just me. I'm not sure that the increased contact time wouldn't be more or less canceled by the smaller forces acting over that contact time. It's not obvious (to me) how this would affect the average tip offset since the cueball will be picking up spin at slower rate. I'll have to look at this in more detail unless you have a fairly intuitive way of seeing this.

Another comment I have--really a semantic one-- is that the "momentum conservation model" is not really a base model that can have other effects added onto it. The "momentum conservation model" is complete and unrefutable, unless of course you want to claim momentum is not conserved. As long as Steve Hegg doesn't show up, I suspect nobody's going to make that claim. The model that *can* be incomplete and/or inadequate is the "fixed endmass model." All postulated mechanisms that suggest squirt does or doesn't depend on whatever are equivalent to suggesting the effective endmass does or doesn't depend on whatever.

Good point, which I obviously didn't appreciate. The effects of a miscue, partial or otherwise, come under this model.

Thanks again for relaying your results. It seems as if you're well on the way to putting this issue to rest.

Jim

 

[pete lafond]

It's not clear to me that this is true, but it's probably just me. I'm not sure that the increased contact time wouldn't be more or less canceled by the smaller forces acting over that contact time. It's not obvious (to me) how this would affect the average tip offset since the cueball will be picking up spin at slower rate. I'll have to look at this in more detail unless you have a fairly intuitive way of seeing this.


Jim

If it helps, a softer tip will cause increase contact time translating to more grab resulting in more spin. Harder tip requires a much softer stroke to acheive the same. (Harder tips will tend to skid more off the CB)

 

[sjm]

As I've mentioned before on the forum, here's a shot I discussed with Mizerak over twenty years ago. I mentioned to him that I had a little trouble with the straight pool break shot below, which has to be hit with high speed inside english. I told him I often overcut the ball, and he explained that I wasn't compensating enough for the squirt. In fact, if you hit this shot with maximum inside and high speed, you must aim for an undercut, whereas most of us are accustomed to aiming for an overcut when we cut a ball in with inside. Squirt can be really tricky to deal with.

 

[mikepage]

It's not clear to me that this is true, but it's probably just me. I'm not sure that the increased contact time wouldn't be more or less canceled by the smaller forces acting over that contact time. It's not obvious (to me) how this would affect the average tip offset since the cueball will be picking up spin at slower rate. I'll have to look at this in more detail unless you have a fairly intuitive way of seeing this.

Jim

One way to see it is to imagine the hard tip is extremely hard and that its contact time is extremely short. Hit a ball with with this tip at an offset of, say, 10 mm. The contact time is so short that the force both during compression and during decompression is acting at 10 mm. You will get a cueball with a spin/speed ratio characteristic of a 10mm offset.

Now hit the same shot with a normal tip with a 1 ms contact time. After compression of the tip the cueball has attained about half its forward speed and about half its spin. It's also moved forward some and rotated some so that the compressed tip has an offset of 10.5 mm instead of 10mm. Then the rest of the acceleration of the ball, during decompression, is occuring at offsets between, say 10.5 and 11.0 mm. I think this cueball, struck at 10 mm will have a spin/speed ratio characteristic of perhaps a 10.5 mm offset. Go now to a somewhat softer tip and the effective offset might increase to 10.6 mm.

If you ignore this effect, then I agree a soft tip and a hard tip give the same result: it's the impulse--the area under the force versus time curve--that matters.

mike page
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[mikepage]

You will get more squirt the harder you hit, this has been known for quite some time. [...]

This, imo, has been as well known and as well established as the idea in 2003 that Iraq had an advanced clandestine WMD program.

mike page
fargo

 

[mikepage]

As I've mentioned before on the forum, here's a shot I discussed with Mizerak over twenty years ago. I mentioned to him that I had a little trouble with the straight pool break shot below, which has to be hit with high speed inside english. I told him I often overcut the ball, and he explained that I wasn't compensating enough for the squirt. In fact, if you hit this shot with maximum inside and high speed, you must aim for an undercut,

Makes sense to here.

whereas most of us are accustomed to aiming for an overcut when we cut a ball in with inside. Squirt can be really tricky to deal with.

I don't understand this last part. Unless you need to compensate for a lot of swerve, inside english shots always need to be aimed thick to compensate for squirt.

mike page
fargo

 

[Colin Colenso]

I wonder if part of the reason many players are convinced that harder shots lead to greater squirt is the effect harder shots have on throw. That is, at high speed, throw is significantly reduced.

So, though the CB may hit the OB (let's use sjm's shot on the previous page as an example) in the same spot, the OB would be overcut more at higher speed as the throw on contact from the CB and OB is a couple of degrees less. Hence, when hitting with power you need to aim to undercut (hit thicker) on the shot.

But if you were playing the same angle shot with Outside English you would need to aim to undercut it slightly as the throw won't turn the OB toward the pocket as much. And because many may miss this shot thick (undercutting) they may assume squirt was the cause, where in fact it may be the change in throw that is to cause.

Just an idea to consider

By the way, in my theory of SPID, it doesn't conclude that hard shot will squirt more, but I suggested that if they do, it might have something to do with Surface Property Induced Deflection. Still, I must admit, there is still a lot for me to learn about the physics and complex interactions and their various dependencies and correlations.

 

[Colin Colenso]

Also, it's worth noting that even slower shots where OB swerve comes into play, the swerve acts in the same direction. ie: IE shots swerve sends OB thicker (undercut), OE swerve sends OB thinner (undercut).

So we have a situation where 2 factors (swerve and throw) combine in the same angular direction such that the harder we hit the CB with IE, the thicker (undercut) we have to aim, and with OE, the harder we hit it, the thinner (overcut) we have to aim.

If squirt is indeed greater with hard shots, we would have a third factor exaggerating the same tendency.

Though, if squirt is not greater at speed, these other two factors would be reason enough for many to mistakenly aim wrongly and then blame their error on squirt.

 

[sjm]

Makes sense to here.



I don't understand this last part. Unless you need to compensate for a lot of swerve, inside english shots always need to be aimed thick to compensate for squirt.

mike page
fargo

Point well taken, and I should have clarified further. I am referring to the very soft hits that are so common in straight pool. On those shots, the swerve tends to be a bigger factor than the squirt. Of course, it's difficult to generalize as tip size and staff stiffness are factors, too. I stand corrected.