0.008 intermediate diff = assymetrical?

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militant02
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0.008 intermediate diff = assymetrical?

Post by militant02 »

i recall another post that broke down how low the intermediate differential of a ball can go before you treat it as a symmetrical ball. does anyone have an idea of what 0.008 int diff would be considered?
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Re: 0.008 intermediate diff = assymetrical?

Post by elgavachon »

militant02 wrote:i recall another post that broke down how low the intermediate differential of a ball can go before you treat it as a symmetrical ball. does anyone have an idea of what 0.008 int diff would be considered?
Asymmetrical. I think that is what the Mojave has. From what I remember the break-off is at .007
I think a wt hole will still move a .008 a little though. The break-off for it not moving is at around .020
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

militant02 wrote:i recall another post that broke down how low the intermediate differential of a ball can go before you treat it as a symmetrical ball. does anyone have an idea of what 0.008 int diff would be considered?
Borderline, but just asymmetrical.
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Re: 0.008 intermediate diff = assymetrical?

Post by militant02 »

ok, thanks. one other question, since the distance from the pin to pap has a different effect with asymmetrical balls versus symmetrical does this effect increase the higher the mass bias value increase?
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

militant02 wrote:ok, thanks. one other question, since the distance from the pin to pap has a different effect with asymmetrical balls versus symmetrical does this effect increase the higher the mass bias value increase?

Pretty much treat it like an asym. flaring ball with intermediate diffs. .007". I treat everything under that as symmetrical.
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Re: 0.008 intermediate diff = assymetrical?

Post by The Kid »

Questions:

1) If one were to have a 4+" Pin-to-PAP on a low asym (.007 or lower) and placed the PSA near the thumb with a large DT weight hole, would the flaring properties change at some point? I know the DT weight hole will increase the total diff., so it will flare more anyhow. But will it lose one of its stable axes to begin flaring like an asym?

2) You (Mo) told me recently that the reason asyms and syms flare differently is that syms have 2 stable axes (Pin 6 3/4" from PAP and Pin on PAP) compared to asyms, which only have one (Pin on PAP). Because all drilled balls are asym, does that mean the second axis' stability is a function of the intermediate diff. (or diff. ratio, perhaps)? That is, is the axis only "stable enough" with intermediate diffs. .007 or less? Beyond that, does it become more and more unstable? For instance, will a ball with an EZ Rev core be more unlike a sym than a 607A or even a 715T?

Thanks as always!
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

The Kid wrote:Questions:

1) If one were to have a 4+" Pin-to-PAP on a low asym (.007 or lower) and placed the PSA near the thumb with a large DT weight hole, would the flaring properties change at some point? I know the DT weight hole will increase the total diff., so it will flare more anyhow. But will it lose one of its stable axes to begin flaring like an asym? YES! IT'S THE MASS PROPERTIES OF THE DRILLED BALL THAT MATTERS!

2) You (Mo) told me recently that the reason asyms and syms flare differently is that syms have 2 stable axes (Pin 6 3/4" from PAP and Pin on PAP) compared to asyms, which only have one (Pin on PAP). Because all drilled balls are asym, does that mean the second axis' stability is a function of the intermediate diff. (or diff. ratio, perhaps)? YES! That is, is the axis only "stable enough" with intermediate diffs. .007 or less? YES! Beyond that, does it become more and more unstable? YES! For instance, will a ball with an EZ Rev core be more unlike a sym than a 607A or even a 715T? YES!

Thanks as always!
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Re: 0.008 intermediate diff = assymetrical?

Post by The Kid »

Cool stuff.

One more:

Seeing as we increase the drilling angle 5* and decrease the VAL angle 5* on a symmetrical ball from an asymmetrical layout due to lower gyroscopic inertia, should we decrease the drilling angle and increase the VAL angle to compensate for extreme asymmetry?

i.e. Comparing a layout for a 916AT (.016/.055) to an Nsane LevRG (.035/.052), [let's assume they're similar enough for comparison] should one alter the LevRG layout because of higher gyroscopic inertia?
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

The Kid wrote:Cool stuff.

One more:

Seeing as we increase the drilling angle 5* and decrease the VAL angle 5* on a symmetrical ball from an asymmetrical layout due to lower gyroscopic inertia, should we decrease the drilling angle and increase the VAL angle to compensate for extreme asymmetry?

i.e. Comparing a layout for a 916AT (.016/.055) to an Nsane LevRG (.035/.052), [let's assume they're similar enough for comparison] should one alter the LevRG layout because of higher gyroscopic inertia?

Please re-word the question. I'm not following.
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Re: 0.008 intermediate diff = assymetrical?

Post by kwettig »

I believe he's asking if we should change the layout for cases of extremely high intermediate differentials as we change the layout for symmetrical equipment. Do we do the opposite as we would for a symmetrical and have a smaller drill angle and a larger val?

So if a symmetrical layout is 60* 30* and a ~.016 int. diff. asym is 55* 35* would a ~.032 int. diff. asym be laid out 50* 40*?
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Re: 0.008 intermediate diff = assymetrical?

Post by The Kid »

I think that about sums it up. My thought process follows this way:

Post-drilled symmetricals have low intermediate differentials. Because of this (I assume), they have lower gyroscopic inertia. Therefore, we add 5* to the drilling angle and take 5* off the VAL angle to cause the ball to lose tilt later.

Post-drilled very asymmetric balls have high intermediate differentials. Because of this (I assume), they have higher gyroscopic inertia. Therefore, we take 5* off the drilling angle and add 5* to the VAL angle to cause the ball to lose tilt sooner.

Perhaps it is inconsequential.
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

kwettig wrote:I believe he's asking if we should change the layout for cases of extremely high intermediate differentials as we change the layout for symmetrical equipment. Do we do the opposite as we would for a symmetrical and have a smaller drill angle and a larger val?

So if a symmetrical layout is 60* 30* and a ~.016 int. diff. asym is 55* 35* would a ~.032 int. diff. asym be laid out 50* 40*?
If you're trying to create identical ball motion, YES! since higher diff. ratio balls transition faster.
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Re: 0.008 intermediate diff = assymetrical?

Post by The Kid »

Mo Pinel wrote: If you're trying to create identical ball motion, YES! since higher diff. ratio balls transition faster.
Is this directly due to gyroscopic inertia?

Also, in what way is gyroscopic inertia linked to the Pin-to-Spin line, if at all?
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

The Kid wrote: Is this directly due to gyroscopic inertia? YES!!!!

Also, in what way is gyroscopic inertia linked to the Pin-to-Spin line, if at all?
THE PRECESSIONAL RATE OF THE PAP INCREASES AS IT PASSES THE PIN TO SPIN LINE, THE MINOR AXIS OF THE ELLIPSE!!!!
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Re: 0.008 intermediate diff = assymetrical?

Post by The Kid »

This. Is. Awesome.
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Re: 0.008 intermediate diff = assymetrical?

Post by EricHartwell »

Mo Pinel wrote: THE PRECESSIONAL RATE OF THE PAP INCREASES AS IT PASSES THE PIN TO SPIN LINE, THE MINOR AXIS OF THE ELLIPSE!!!!
Does that mean the flare increases?

Doesnt the spin also increase after the axis migration passes the pin to spin line?
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Re: 0.008 intermediate diff = assymetrical?

Post by Mo Pinel »

EricHartwell wrote: Does that mean the flare increases?

Doesnt the spin also increase after the axis migration passes the pin to spin line?
The real answer is that the spin rate increases after ball crosses the pin to spin line, which does result in an increase in flare.
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Re: 0.008 intermediate diff = assymetrical?

Post by dougsterner »

Wow....I used to think I was a reasonably intelligent guy....until now that is :-)
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