Physics debate

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TallGrass
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Re: Physics debate

Post by TallGrass » Thu Jan 19, 2023 10:10 am

Related Post: https://telemarktalk.com/viewtopic.php? ... 460#p56297


Perhaps this can be simplified as a discussion of Component Vectors

V-> = (Vx, Vy)

Image

The wrap-around(-the-heel) cable has to be under tension or it would fall off.
The heel-pivot is higher than it's connection to the frame.
Hence there is a downward component vector resisting the raising of the heel,
which becomes larger as the heel is raised.
Image
Image
Image

How to affect how much the heel is "anchored" or "locked" versus "free" seems well-established.
The component vectors should be easy to visualize, as well as how the following system functions.
Source: http://www.smhc.co.uk/objects_item.asp?item_id=33040 (<-- short read)
Image Image


If you've read this far and would like more of a rabbithole, check this out. It's in German, but even scrolling through the photos gives an idea of this paper's scope.
https://docplayer.org/18680858-Alpiner- ... en-at.html

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DG99
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Re: Physics debate

Post by DG99 » Thu Jan 19, 2023 1:19 pm

Nice! I think that’s the missing link, the force vector components diagram.



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GrimSurfer
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Re: Physics debate

Post by GrimSurfer » Thu Jan 19, 2023 1:50 pm

DG99 wrote:
Thu Jan 19, 2023 1:19 pm
Nice! I think that’s the missing link, the force vector components diagram.
I can certainly see it’s appeal… no scale, all force vectors of equal magnitude, symmetry that bears no resemblance to real forces, pretty colours.

Like an idea, without thought or logic.

I’ve asked Johnny to cancel my account. I’m not getting anything from corresponding with people who are too lazy (or stupid) to think. Or maybe there’s snow. IDK… you choose whatever excuse makes you happy.
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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lowangle al
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Re: Physics debate

Post by lowangle al » Thu Jan 19, 2023 2:09 pm

GrimSurfer wrote:
Wed Jan 18, 2023 10:03 pm


This will likely be my last post on this thread because, frankly, I’m happy to leave people believing in whatever they really want. Even if that includes the magical properties of crystals, the infallibility of the zodiac, or the limitless power of cables.

I thought you were on to something here. :)

At this point it might be a good idea to move this science discussion over to the OT forum. Physics Debate #2. It's no longer about the skiing. There is no debate on what binding activity and tip pressure do for your skiing. This thread will just confuse people who are looking for info. It doesn't matter to me though, I'm not here for info.

Carry on.



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connyro
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Re: Physics debate

Post by connyro » Thu Jan 19, 2023 2:13 pm

GrimSurfer wrote:
Thu Jan 19, 2023 1:50 pm
DG99 wrote:
Thu Jan 19, 2023 1:19 pm
Nice! I think that’s the missing link, the force vector components diagram.
I can certainly see it’s appeal… no scale, all force vectors of equal magnitude, symmetry that bears no resemblance to real forces, pretty colours.

Like an idea, without thought or logic.

I’ve asked Johnny to cancel my account. I’m not getting anything from corresponding with people who are too lazy (or stupid) to think. Or maybe there’s snow. IDK… you choose whatever excuse makes you happy.
images.jpeg



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Stephen
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Re: Physics debate

Post by Stephen » Thu Jan 19, 2023 2:20 pm

If @GrimSurfer thinks that a 75mm binding, with a cable, is basically a free-pivot binding, that would explain a lot.
See: viewtopic.php?f=1&t=5450&start=470#p56313
He chose not to answer the question I asked about that.



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TallGrass
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Re: Physics debate

Post by TallGrass » Thu Jan 19, 2023 2:22 pm

GrimSurfer wrote:
Thu Jan 19, 2023 1:50 pm
no scale, all force vectors of equal magnitude, symmetry that bears no resemblance to real forces, pretty colours.
Here's the scale
Image
The force vectors are not of equal magnitude, though I realize magnitude can be depicted differently (line thickness, line length, numeric notation, ...)
Above, a vector of roughly 6.4 units at a the angle shown, is broken down into it's component vectors, 5 vertically (Y axis) and 4 horizontally (X axis).
Per Pythagorean Theorem ~6.4^2 = √(5.0^2 + 4.0^2) = √41
(Yes, I realize √41 isn't exactly 6.4 (6.40312423743...), significant digits and all that...)

So, if it's line thickness that's the catch, oops. Here is a re-do with the vertical in Red 3pt wide, horizontal in Blue 4pt wide, and the diagonal in Purple (red+blue) 5pt wide.
Image

I'm sorry if the angle in the photo is not exactly the same as a 3-4-5 right triangle, but the boot-binding photo was handy, and it's clear it could be inclined to match that angle per prior photos.

Not trying to aggravate anyone, just civilly working toward understanding.
I'm open to any constructive comments or critiques.
Thank you again.

P.S.
Anyone wanting to illustrate, there's MS Paint at https://mspaint.humanhead.com/. Between it, screenshots, left/right-click options, uploading to imgur for a link to embed here via [img] code, one should be able to show what they are trying to describe.



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tkarhu
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Re: Physics debate

Post by tkarhu » Thu Jan 19, 2023 2:47 pm

lowangle al wrote:
Thu Jan 19, 2023 2:09 pm
At this point it might be a good idea to move this science discussion over to the OT forum. Physics Debate #2. It's no longer about the skiing. There is no debate on what binding activity and tip pressure do for your skiing. This thread will just confuse people who are looking for info. It doesn't matter to me though, I'm not here for info.
It is true that this thread has been more about gear than skiing lately, but that is not a reason to move things to off topic IMO. After all, more threads are about gear than skiing technique on this forum. :D

EDIT: Or if Al meant closing the discussion in this thread, it sounds like a good idea.

Thinking things through together, I have understood what kind of characteristics switchback and 22 design axl bindings have. A lot of their difference comes from where and how cables are attached. Others have reached same conclusions elsewhere, see citation below. It might have been nothing new to @lowangle al so I do see why this might not have felt relevant. Just old things expressed in an new way.
Consider 22 Designs Axl and Voile Switchback as examples. The reputation for these two bindings are at opposite ends of the activity spectrum, with the Switchback being a ‘neutral’ cable binding and Axl, the free-pivot descendant of the Hammerhead, the epitome of adjustability and the benchmark of comparison for tele power. […] Resistance to heel lift can be determined with a lil’ trigonometry by splitting the vector representing the spring force of the cable into vertical and horizontal components. Analyzed this way it is easy to see why the Switchback is more neutral than an Axl in position 3 (or 2 or 1).
https://earnyourturns.com/34754/diy-2-p ... orce-luke/

Sad that everybody has not seen writing this all as a collaborative effort, spending a lot of time on it. I feel I have met people in the process.



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Lhartley
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Re: Physics debate

Post by Lhartley » Thu Jan 19, 2023 3:02 pm

tkarhu wrote:
Thu Jan 19, 2023 2:47 pm
lowangle al wrote:
Thu Jan 19, 2023 2:09 pm
At this point it might be a good idea to move this science discussion over to the OT forum. Physics Debate #2. It's no longer about the skiing. There is no debate on what binding activity and tip pressure do for your skiing. This thread will just confuse people who are looking for info. It doesn't matter to me though, I'm not here for info.
It is true that this thread has been more about gear than skiing lately, but that is not a reason to move things to off topic IMO. After all, more threads are about gear than skiing technique on this forum. :D

EDIT: Or if Al meant closing the discussion in this thread, it sounds like a good idea.

Thinking things through together, I have understood what kind of characteristics switchback and 22 design axl bindings have. A lot of their difference comes from where and how cables are attached. Others have reached same conclusions elsewhere, see citation below. It might have been nothing new to @lowangle al so I do see why this might not have felt relevant. Just old things expressed in an new way.
Consider 22 Designs Axl and Voile Switchback as examples. The reputation for these two bindings are at opposite ends of the activity spectrum, with the Switchback being a ‘neutral’ cable binding and Axl, the free-pivot descendant of the Hammerhead, the epitome of adjustability and the benchmark of comparison for tele power. […] Resistance to heel lift can be determined with a lil’ trigonometry by splitting the vector representing the spring force of the cable into vertical and horizontal components. Analyzed this way it is easy to see why the Switchback is more neutral than an Axl in position 3 (or 2 or 1).
https://earnyourturns.com/34754/diy-2-p ... orce-luke/

Sad that everybody has not seen writing this all as a collaborative effort, spending a lot of time on it. I feel I have met people in the process.
I also have learned a few things about the mentioned bindings from these threads, and have found a real appreciation the mechanics of those bindings. Ironic considering the purpose of these threads was likely a not so sneaky way to promote xplore systems.



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TheMusher
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Re: Physics debate

Post by TheMusher » Thu Jan 19, 2023 3:12 pm

tkarhu wrote:
Thu Jan 19, 2023 2:47 pm
https://earnyourturns.com/34754/diy-2-p ... orce-luke/

Sad that everybody has not seen writing this all as a collaborative effort, spending a lot of time on it. I feel I have met people in the process.
Great link! This guy Dostie obviously went down this road for us a few years ago.

He concisely summarizes the forces, it’s vectors and the tip pressure relating to the cables.

Think it’s be a much more factual and informative read than this collective clusterhug of a thread :D



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