Physics debate

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GrimSurfer
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Re: Physics debate

Post by GrimSurfer » Mon Jan 02, 2023 8:20 pm

I’ve provided my views on the binding for which I provided a photo.

You can call it whatever you like. As long as we’re all talking about the same thing, it really doesn’t matter.

Anyone is free to post contrasting views, opinions. For the purpose of clarity, however, just be sure to explain how the various parts of the binding work (in your view, preferably while respecting things like the laws of nature, physics, etc).

Such comments will stand on their own and stimulate discussion more than “is, isn’t” or personal attacks (which you @Stephen have not done… just to be clear on that).
We dreamed of riding waves of air, water, snow, and energy for centuries. When the conditions were right, the things we needed to achieve this came into being. Every idea man has ever had up to that point about time and space were changed. And it keeps on changing whenever we dream. Bio mechanical jazz, man.

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Stephen
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Re: Physics debate

Post by Stephen » Mon Jan 02, 2023 8:35 pm

@GrimSurfer, not to be snarky, but you seem to sometimes not answer the question.
I asked if the picture I posted was the one you referred to in your most recent post (you didn't answer this question).
GrimSurfer wrote:
Mon Jan 02, 2023 7:16 pm
You will recall, though, that all of my comments have been restricted on NN 75mm 3 pin bindings. (I highlighted this specifically in the preamble to my last long post by including a picture of the exact type of binding I was talking about).

I have offered no views to date on truly active bindings… i.e. those which allow longitudinal boot movement through any kind of sliding plate or hinge. Different fish.
I then went on to say:
Stephen wrote:
Mon Jan 02, 2023 7:35 pm
... this is an active binding, whether you know it or not.
Sliding plate or hinge” has nothing to do with this and may be a mistaken assumption on your part.
I could be mistaken, but I sense you are, to some degree, trying to wiggle your way out of this.
No one wants to crucify you, but if you're mistaken, I think the brave thing to do would be to just say so.

Or, ask clarifying questions until we're all on the same page, if that's possible.
4CD66135-FC0E-48E6-ADA3-05DF4A7E76AC.jpeg



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Re: Physics debate

Post by GrimSurfer » Mon Jan 02, 2023 8:37 pm

Nick BC wrote:
Mon Jan 02, 2023 7:33 pm
Then every so often someone would come along with a post, which provoked a s**t show and the original poster would stand firm and it would cycle on and eventually die out.
I don’t know about standing firm. Is that the same as fully explaining “why” I hold the views I do on NN 3 pin 75mm bindings with a cable?

It’s a rhetorical question. Not intending to draw you into the cycle of insanity going on at the moment.

Keep the edges sharp and shiny while enjoying those carving turns!
We dreamed of riding waves of air, water, snow, and energy for centuries. When the conditions were right, the things we needed to achieve this came into being. Every idea man has ever had up to that point about time and space were changed. And it keeps on changing whenever we dream. Bio mechanical jazz, man.



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Re: Physics debate

Post by GrimSurfer » Mon Jan 02, 2023 8:47 pm

Stephen wrote:
Mon Jan 02, 2023 8:35 pm
not to be snarky, but you seem to sometimes not answer the question.
I asked if the picture I posted was the one you referred to in your most recent post (you didn't answer this question).
GrimSurfer wrote:
Mon Jan 02, 2023 7:16 pm
You will recall, though, that all of my comments have been restricted on NN 75mm 3 pin bindings. (I highlighted this specifically in the preamble to my last long post by including a picture of the exact type of binding I was talking about).

I have offered no views to date on truly active bindings… i.e. those which allow longitudinal boot movement through any kind of sliding plate or hinge. Different fish.
I then went on to say:
Stephen wrote:
Mon Jan 02, 2023 7:35 pm
... this is an active binding, whether you know it or not.
Sliding plate or hinge” has nothing to do with this and may be a mistaken assumption on your part.
I could be mistaken, but I sense you are, to some degree, trying to wiggle your way out of this.
No one wants to crucify you, but if you're mistaken, I think the brave thing to do would be to just say so.

Or, ask clarifying questions until we're all on the same page, if that's possible.
The purpose of the photo was to be as clear as possible.

In that vein… I don’t consider that the binding in my picture to be active. Full stop.

Reasons:

I would consider an active binding to be one that changes the location or magnitude pressure on the ski without skier intervention. Simply having a moveable element (like a wire or cable) does not, in my opinion, make it active unless that wire or cable shifts skier weight as a first order effect.

This distinction is important because there are bindings that do have a moveable element that does shift skier weight. Some of these are manual (which I wouldn’t consider active either). Some are automatic (which could be called active if they fulfill a function independent of a skier’s weight transfer).

But the NN 3 pin 75mm doesn’t fall into this category.

End reasons.

I have described (in my long post):how the NN binding works, with and without a cable. This description makes it clear that the cable acts as a control element on the boot (of which the heel is a part… just so that we avoid that semantic rabbit hole).

Are there specific things I said (pls quote) what I said that you disagree with? If so, what is your alternate view?

Pictures might help too because they get us around the terminology issue, which seems to be one of the derailing forces in some technical discussions.

I’m not trying to wiggle out of anything. I’ve been clear all along about the bindings I’m talking about. Even provided a photo… now I’m having to use redundant expressing like NN 3 pin 75mm.

I get the impression that folks don’t really have a *technical* response to my long post. I wish they did… I’d enjoy considering an alternate view that doesn’t violate laws of physics etc.
Last edited by GrimSurfer on Mon Jan 02, 2023 9:05 pm, edited 2 times in total.
We dreamed of riding waves of air, water, snow, and energy for centuries. When the conditions were right, the things we needed to achieve this came into being. Every idea man has ever had up to that point about time and space were changed. And it keeps on changing whenever we dream. Bio mechanical jazz, man.



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Stephen
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Re: Physics debate

Post by Stephen » Mon Jan 02, 2023 9:03 pm

GrimSurfer wrote:
Mon Jan 02, 2023 8:47 pm

I don’t consider that the binding in my picture to be active. I would consider an active binding to be one that changes the location or magnitude pressure on the ski without skier intervention. Simply having a moveable element (like a wire or cable) does not, in my opinion, make it active unless that wire or cable shifts skier weight as a first order effect.

This distinction is important because there are bindings that do have a moveable element that does shift skier weight. Some of these are manual (which I wouldn’t consider active either). Some are automatic (which could be called active if they fulfill a function independent of a skier’s weight transfer).

I have described (in my long post):how the NN binding works, with and without a cable.

Are there specific things I said (pls quote) what I said that you disagree with? If so, what is your alternate view?

Pictures might help too because they get us around the terminology issue, which seems to be one of the derailing forces in some technical discussions.
OK, maybe we are getting somewhere, here.
You say:
GrimSurfer wrote:
Mon Jan 02, 2023 8:47 pm
I don’t consider that the binding in my picture to be active.
And yet, most all the folks here will disagree with you on that one, key point.
It is the key point of this very long post thread (although not the original point :lol: ).

I don't really know the true defiition of "Active Binding," if there even is one.
But in common usage, it is one that restricts the lifting of the heel, which allows the skier to trasfer weight to the front of the ski MORE than he would be able to without an active binding, such as a free pivot binding (don't let "free pivot" derail the conversation).

I found this thread here, talking about that. Haven't read it, so don't know WHAT it says, but the topic is germane.
Neutral vs. Active Bindings
viewtopic.php?f=1&t=2785

Snip from that post thread, sorry it's blurry.
.
active.JPG
Last edited by Stephen on Mon Jan 02, 2023 9:12 pm, edited 1 time in total.



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Re: Physics debate

Post by GrimSurfer » Mon Jan 02, 2023 9:07 pm

Stephen wrote:
Mon Jan 02, 2023 9:03 pm
GrimSurfer wrote:
Mon Jan 02, 2023 8:47 pm

I don’t consider that the binding in my picture to be active. I would consider an active binding to be one that changes the location or magnitude pressure on the ski without skier intervention. Simply having a moveable element (like a wire or cable) does not, in my opinion, make it active unless that wire or cable shifts skier weight as a first order effect.

This distinction is important because there are bindings that do have a moveable element that does shift skier weight. Some of these are manual (which I wouldn’t consider active either). Some are automatic (which could be called active if they fulfill a function independent of a skier’s weight transfer).

I have described (in my long post):how the NN binding works, with and without a cable.

Are there specific things I said (pls quote) what I said that you disagree with? If so, what is your alternate view?

Pictures might help too because they get us around the terminology issue, which seems to be one of the derailing forces in some technical discussions.
OK, maybe we are getting somewhere, here.
You say:
GrimSurfer wrote:
Mon Jan 02, 2023 8:47 pm
I don’t consider that the binding in my picture to be active.
And yet, most all the folks here will disagree with you on that one, key point.
It is the key point of this very long post thread (although not the original point :lol: ).

I don't really know the true defiition of "Active Binding," if there even is one.
But in common usage, it is one that restricts the lifting of the heel, which allows the skier to trasfer weight to the front of the ski MORE than he would be able to without an active binding, such as a free pivot binding (don't let "free pivot" derail the conversation).

I found this thread here, talking about that. Haven't read it, so don't know WHAT it says, but the topic is germane.
viewtopic.php?f=1&t=2785
A NNN BC has a bumper that restricts lifting of the heel. You can use ones with different firmness. The hardest makes it harder to lift the heel than a cable does.

But I don’t consider a NNN BC with hard bumper to be an active boot… for all the same reasons I use of the NN 3 pin 75mm binding.

Just scanned the discussion that you provided the link to. I’m always concerned when the discussion goes from the binary (active or inactive) to using terms like “more active” or “less active”. It reminds me of the joke about being a little pregnant.

So it’s hard to draw anything definitive from that discussion. Things start getting squishy from the second post.
We dreamed of riding waves of air, water, snow, and energy for centuries. When the conditions were right, the things we needed to achieve this came into being. Every idea man has ever had up to that point about time and space were changed. And it keeps on changing whenever we dream. Bio mechanical jazz, man.



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Stephen
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6’3” / 191cm — 172# / 78kg, size 47 / 30 mondo

Re: Physics debate

Post by Stephen » Mon Jan 02, 2023 9:19 pm

There's nothing squishy here.
You're an absolutist, so either a binding has resistance to heel lift, which is transferred to the front of the ski, or it does not.

A tech binding in tour mode is free pivot and transmits NO force (miniscule, due to friction in the pivot pin) to the front of the ski.
Anything beyond that is SOME degree of active.
Folks don't usually think of that aspect of the low-active bindings (Xplore, NNN BC, straight 3 Pin, NNN, whatever), but as soon as you add a cable, the binding is absolutely active, unless there is NO tension on the cable and it's just hanging on the back of the boot.

That is the purpose of the hard flexors for NNN BC, Xplore, to make the binding more active (without using a cable).



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Re: Physics debate

Post by GrimSurfer » Mon Jan 02, 2023 9:40 pm

Stephen wrote:
Mon Jan 02, 2023 9:19 pm
There's nothing squishy here.
You're an absolutist, so either a binding has resistance to heel lift, which is transferred to the front of the ski, or it does not.

A tech binding in tour mode is free pivot and transmits NO force (miniscule, due to friction in the pivot pin) to the front of the ski.
Anything beyond that is SOME degree of active.
Folks don't usually think of that aspect of the low-active bindings (Xplore, NNN BC, straight 3 Pin, NNN, whatever), but as soon as you add a cable, the binding is absolutely active, unless there is NO tension on the cable and it's just hanging on the back of the boot.

That is the purpose of the hard flexors for NNN BC, Xplore, to make the binding more active (without using a cable).
I might be an absolutist, but I’m am consistent.

First, it is my view that the cable does not (in itself) transfer any force that does not cancel itself out between the boot and the binding. I base this view on Newton’s Third Law of motion. This isn’t me being snooty… I didn’t invent the darned law, I merely observe it because, as a law, it is an immutable rule of physics.

As I’ve stated, the NN 3 pin 75 mm cable is a control element for the boot. It is a necessity of design because it’s the only way to change flex characteristics without changing boots.

Said another way, the boot is harder to rotate when the cables are used. This is because of the cable—>boot interaction (1st order effect), not the boot—>binding—>ski interaction (2nd order effect).

Regardless, the cable does change the flex point of the sole. It moves it forward slightly. This places it closer to the ball of the foot, which is the forward most force bearing part of the foot. This allows the skier’s mass to be more effectively applied to the ski. With or without the cable, however, the mass of that the skier can place on the ski is ultimately the same.

That’s my position. Which part, specifically, do you disagree with?
We dreamed of riding waves of air, water, snow, and energy for centuries. When the conditions were right, the things we needed to achieve this came into being. Every idea man has ever had up to that point about time and space were changed. And it keeps on changing whenever we dream. Bio mechanical jazz, man.



User avatar
Stephen
Posts: 1464
Joined: Thu Aug 06, 2020 12:49 am
Location: PNW USA
Ski style: Aspirational
Favorite Skis: Armada Tracer 118 (195), Gamme (210), Ingstad (205), Objective BC (178)
Favorite boots: Alfa Guard Advance, Scarpa TX Pro
Occupation: Beyond
6’3” / 191cm — 172# / 78kg, size 47 / 30 mondo

Re: Physics debate

Post by Stephen » Mon Jan 02, 2023 10:01 pm

GrimSurfer wrote:
Mon Jan 02, 2023 9:40 pm
Stephen wrote:
Mon Jan 02, 2023 9:19 pm
There's nothing squishy here.
You're an absolutist, so either a binding has resistance to heel lift, which is transferred to the front of the ski, or it does not.

A tech binding in tour mode is free pivot and transmits NO force (miniscule, due to friction in the pivot pin) to the front of the ski.
Anything beyond that is SOME degree of active.
Folks don't usually think of that aspect of the low-active bindings (Xplore, NNN BC, straight 3 Pin, NNN, whatever), but as soon as you add a cable, the binding is absolutely active, unless there is NO tension on the cable and it's just hanging on the back of the boot.

That is the purpose of the hard flexors for NNN BC, Xplore, to make the binding more active (without using a cable).
I might be an absolutist, but I’m am consistent.

First, it is my view that the cable does not (in itself) transfer any force that does not cancel itself out between the boot and the binding. I base this view on Newton’s Third Law of motion. This isn’t me being snooty… I didn’t invent the darned law, I merely observe it because, as a law, it is an immutable rule of physics.

As I’ve stated, the NN 3 pin 75 mm cable is a control element for the boot. It is a necessity of design because it’s the only way to change flex characteristics without changing boots.

Said another way, the boot is harder to rotate when the cables are used. This is because of the cable—>boot interaction (1st order effect), not the boot—>binding—>ski interaction (2nd order effect).

Regardless, the cable does change the flex point of the sole. It moves it forward slightly. This places it closer to the ball of the foot, which is the forward most force bearing part of the foot. This allows the skier’s mass to be more effectively applied to the ski. With or without the cable, however, the mass of that the skier can place on the ski is ultimately the same.

That’s my position. Which part, specifically, do you disagree with?
For the sake of economy, I will say that I don’t particularly disagree with any of the above post. And I don’t think anyone has particularly quibbled with you on those points, but I may have missed something on that.
Where things seem to have gone sideways is the idea of being able to apply pressure to the front of the ski, which, iirc, you said was not possible or doesn’t happen with a cable binding.
That would be buried someplace in all that’s been said so far.
Do I have have that right, or not?



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Re: Physics debate

Post by GrimSurfer » Mon Jan 02, 2023 10:05 pm

Stephen wrote:
Mon Jan 02, 2023 10:01 pm
GrimSurfer wrote:
Mon Jan 02, 2023 9:40 pm
Stephen wrote:
Mon Jan 02, 2023 9:19 pm
There's nothing squishy here.
You're an absolutist, so either a binding has resistance to heel lift, which is transferred to the front of the ski, or it does not.

A tech binding in tour mode is free pivot and transmits NO force (miniscule, due to friction in the pivot pin) to the front of the ski.
Anything beyond that is SOME degree of active.
Folks don't usually think of that aspect of the low-active bindings (Xplore, NNN BC, straight 3 Pin, NNN, whatever), but as soon as you add a cable, the binding is absolutely active, unless there is NO tension on the cable and it's just hanging on the back of the boot.

That is the purpose of the hard flexors for NNN BC, Xplore, to make the binding more active (without using a cable).
I might be an absolutist, but I’m am consistent.

First, it is my view that the cable does not (in itself) transfer any force that does not cancel itself out between the boot and the binding. I base this view on Newton’s Third Law of motion. This isn’t me being snooty… I didn’t invent the darned law, I merely observe it because, as a law, it is an immutable rule of physics.

As I’ve stated, the NN 3 pin 75 mm cable is a control element for the boot. It is a necessity of design because it’s the only way to change flex characteristics without changing boots.

Said another way, the boot is harder to rotate when the cables are used. This is because of the cable—>boot interaction (1st order effect), not the boot—>binding—>ski interaction (2nd order effect).

Regardless, the cable does change the flex point of the sole. It moves it forward slightly. This places it closer to the ball of the foot, which is the forward most force bearing part of the foot. This allows the skier’s mass to be more effectively applied to the ski. With or without the cable, however, the mass of that the skier can place on the ski is ultimately the same.

That’s my position. Which part, specifically, do you disagree with?
For the sake of economy, I will say that I don’t particularly disagree with any of the above post. And I don’t think anyone has particularly quibbled with you on those points, but I may have missed something on that.
Where things seem to have gone sideways is the idea of being able to apply pressure to the front of the ski, which, iirc, you said was not possible or doesn’t happen with a cable binding.
That would be buried someplace in all that’s been said so far.
Do I have have that right, or not?
I have said, and continue to say, that the *cable* does not apply any force to the ski. Doing so would violate a law of motion.

The interaction between the cable and the binding sums to zero. That happens in accordance with a law of motion (the 3rd one).
We dreamed of riding waves of air, water, snow, and energy for centuries. When the conditions were right, the things we needed to achieve this came into being. Every idea man has ever had up to that point about time and space were changed. And it keeps on changing whenever we dream. Bio mechanical jazz, man.



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