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Steering: two points of view. - Page 5

post #121 of 148
Max,

Quote:
So, increase pressure along the edge of the ski in front of the boot and decrease pressure along the edge of the ski behind the boot. Sounds like a great way to cause a skid.
If you read more of the post,

Quote:
Stated differently, on a steep ice slope, the outside ski is pulled into the surface (rather than pushed against) using rotary touque by exerting the aductor muscle group.
you will see that the whole ski is being pulled into the snow while some rotary torque is being applied to keep the tip engaged along with guiding the ski along an arc. I really don't think anyone has the rotary strength to rotate an effectivally edged and weighted ski enough to make the tail breakaway and cause a skid as you are implying unless they are going 2 mph on a pair of 80 mm skis, and even them b/c the ski is so flat on the snow. I am talking about dynamic sking on hard snow. It works for the world cup skiers.

RW
post #122 of 148
Quote:
Originally Posted by Ron White View Post
I really don't think anyone has the rotary strength to rotate an effectivally edged and weighted ski enough to make the tail breakaway and cause a skid as you are implying...
I'd have to disagree. I find it rather easy to kill a nice carve with a twisting movement.

Quote:
Originally Posted by Ron White View Post
I am talking about dynamic sking on hard snow. It works for the world cup skiers.
Really? I spoke with a coach that has plenty of WC experience about this and he told me they don't coach a rotary movement to tighten the arc.

If you want to side load then why not do it without a twist?
post #123 of 148
Quote:
Originally Posted by Bob Peters View Post
Isn't sideslipping (which is sort of the mother of all skids) the whole topic of discussion for the last several posts? That's certainly how I read Ron White's comments.
No, as Ron's post above attests, we are talking about carving on hard snow. The sideslipping was in answer to Prof PM's questions.
post #124 of 148
Max,

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Really? I spoke with a coach that has plenty of WC experience about this and he told me they don't coach a rotary movement to tighten the arc.
I'm not talking about tightening the arc. I am talking about enhancing edge engagement.

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If you want to side load then why not do it without a twist?
Because of the design and shape of the ski.

RW
post #125 of 148
mmcknison,

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When we flex the leg, the tibial bone rotates inward. Similarly, when we extend or straighten the leg, it rotates outward. I would suspect that a similar reaction occurs in the femur (which of course would be turning in the hip socket) as these movements occur.
Very interesting. If I understand this correctly, during a turn, the outside extended leg is rotating outward form the turn and the inside flexed leg is also rotating out of the turn shape. Hmmmmm gives active leg rotation a little different light.

Rw
post #126 of 148
Thread Starter 
Anybody care to comment on how this relates to skiing in snow that's not soft, but not boiler plate, say your able to dig you skis a couple of inches into it. Consider the direction of the force that's making you turn. Consider the apex of the turn in conjunction with this and consider for a moment, avoiding a rock stump or tree, but continuing on the same line afterwards. Consider using a carving-type action with only the front half of the ski heavily bent out of shape, tails be damned, and following it with a carving action of the now-heavily waited tails with the tips doing not much. I see lots of room for rotary skills to aid carving there. Mind you it's kind of like teaching trail-braking to new motorcycle riders; you might want them to learn the basics first.
post #127 of 148
Quote:
Originally Posted by Ron White View Post
I'm not talking about tightening the arc. I am talking about enhancing edge engagement.
For what purpose? Is the edge letting go while you are arcing?
post #128 of 148
Max,

I have explained the purpose over and over and you are choosing not to get it. I know your alliegence is to a different forum than this and you will choose not to understand anything about rotary movements. I am fine with that, but I won't waiste my time on something you chose not to get.
RW
post #129 of 148
Ghost,

I think you might be confusing pressure control movements for edging movements.

RW
post #130 of 148
Thread Starter 
Quote:
Originally Posted by Ron White View Post
Ghost,

I think you might be confusing pressure control movements for edging movements.

RW
I don't think so. Please elaborate.
post #131 of 148
ghost,

Quote:
Anybody care to comment on how this relates to skiing in snow that's not soft, but not boiler plate, say your able to dig you skis a couple of inches into it. Consider the direction of the force that's making you turn. Consider the apex of the turn in conjunction with this and consider for a moment, avoiding a rock stump or tree, but continuing on the same line afterwards. Consider using a carving-type action with only the front half of the ski heavily bent out of shape, tails be damned, and following it with a carving action of the now-heavily waited tails with the tips doing not much. I see lots of room for rotary skills to aid carving there. Mind you it's kind of like teaching trail-braking to new motorcycle riders; you might want them to learn the basics first.
I guess I don't understand the question or senerio you describe or even why this is a valid senerio. In the apex of a carved turn (max edge angle to the snow), being able to first wieght (or pressure) the tips and then the tails (still in the apex?) and how this relates to rotary skills to aid carving??
Rw
post #132 of 148
Quote:
Originally Posted by Ron White View Post
I really don't think anyone has the rotary strength to rotate an effectivally edged and weighted ski enough to make the tail breakaway and cause a skid as you are implying...
Quote:
Originally Posted by Ron White View Post
I'm not talking about tightening the arc. I am talking about enhancing edge engagement.
Quote:
Originally Posted by Ron White View Post
I have explained the purpose over and over and you are choosing not to get it. I know your alliegence is to a different forum than this and you will choose not to understand anything about rotary movements. I am fine with that, but I won't waiste my time on something you chose not to get.
I'm trying to understand why you twist the skis when you are arcing on hard snow. You've said to enhance edge engagement. OK, but why does the edge engagement need to be enhanced? Do you have any pictures or video of you skiing on hard snow that would show your body position and angles while you are applying the twist?
post #133 of 148
Thread Starter 
Take a step back and consider the turn shape as cut in the surface of the snow. There is a definite apex at some point in the turn as it sits there. Now there are different ways to go through that apex. You can go through it evenly balanced, torque neutral, or not, smoothly, dynamically, etcetera. One way, not the only way, but certainly one way is as follows.

You ski past that apex. At one point in time your tips are going through the apex and the integral of the pressure forces you in a direction such that the line of action of the net force acting on your cm goes through the apex and your cm with a sideways (towards the centre of the turn, centripetal, not center-fleeing) and a rearward component to it. Later as your tails are going through the apex the line of action of the net force acting on you goes through the apex and tails of your skis pointing at you cm with a sideways and a forward component. You are getting the bulk of your turning force from the tips at the early point in the turn. As there is more force being dealt to you by the tips at first, their grip is critical and you must dig in that edge using some rotary. Of course tipping and pressure control are also requirements. As the tails go through the apex, the tips are no longer forcing the turn, but the tails are and you must pressure the tipped tails and use some rotary in the other direction to keep them from slipping out. At that point the tips are done with the turn so they don't need to do anything.
post #134 of 148
Quote:
Originally Posted by Ghost View Post
...As there is more force being dealt to you by the tips at first, their grip is critical and you must dig in that edge using some rotary.
Why must you use rotary here? What happens if you don't?
post #135 of 148
Thread Starter 
Quote:
Originally Posted by Max_501 View Post
Why must you use rotary here? What happens if you don't?
Just a guess on my part, a non-carved BPST:.

In the situation I'm thinking of the ski is being bent so far and the curve so tight at the apex (think a rapidly decreasing radius turn that opens up quickly afterwards) that the ski would not hold without some extra pressure, which has a large component toward the edge requiring some torque. Also in the case I'm thinking of, you do not have enough pressure with your weight evenly distributed along the whole ski, but you do have enough with most of your weight on the front of the ski. The ski holds the curve even in the apex, but only about half a ski at a time as that part of the ski goes through the tightest bend and you place your weight where it's needed. As you go through the apex you are torque neutral, but when the tips go through they have more weight and when the tails go through the tails have more weight (we can do it with one ski and twice as much bend or two skis at their limit).
post #136 of 148
Quote:
Originally Posted by Ghost View Post
...that the ski would not hold without some extra pressure, which has a large component toward the edge requiring some torque.
I understand why it requires extra pressure. But why extra torque (in other words, why do you need to add more torque than is already present)?
post #137 of 148
Thread Starter 
Max,
Take a ruler and hold it in the middle betwixt thumb and forefinger, touching the flat parts (thumb is like a ski boot). Now place one quarter of it's length on the desk in front of you (with three quarters hanging in the air not touching anything), keeping it flat to the surface of the desk and push down. Pure pressure, no torque required. Now tip it on edge and push down. Notice that it will twist in your grip. Consider the extreme: put it up to a 90 degree edge angle and all of that extra pressure on the front is pure rotary torque.

Now in skiing the tails are not hanging in the air most times, but if you are to have more pressure on the tips than the tails and the skis are tipped there will be a rotary component as illustrated above (zero pressure on tails instead of just less pressure on tails).
post #138 of 148
Quote:
Originally Posted by Ghost View Post
Now in skiing the tails are not hanging in the air most times, but if you are to have more pressure on the tips than the tails and the skis are tipped there will be a rotary component as illustrated above (zero pressure on tails instead of just less pressure on tails).
I understand that there is a rotary component. However, I do not understand why you are adding extra rotary to the equation.
post #139 of 148
Thread Starter 
You push your skis against the snow. The direction of the push determines how much "rotary" is added. I don't know how much is "extra", but you may at times need to push more towards the edge than towards the base in order not to have the tips slip out. This does reduce available grip at the tails. If the tails are not bent as far, they may not need as much grip. There is a fine line you can't go over without loosing the tails, but that line is not always "torque neutral".
post #140 of 148
Quote:
Originally Posted by Ghost View Post
I don't know how much is "extra", but you may at times need to push more towards the edge than towards the base in order not to have the tips slip out.
Yes, side-loading. I understand that. But I don't understand why you would add a "twist" to it.
post #141 of 148
Thread Starter 
If you side-load the tips more than the tails there will be a twist. You are not adding a twist; you are adding more side-load to the tip than you are to the tails. You do that because the tips enter the tighter section of the turn before the tails, and you do the reverse because the tails are still in that tight section when the tips are clear.
post #142 of 148
Quote:
Originally Posted by Ghost View Post
If you side-load the tips more than the tails there will be a twist. You are not adding a twist; you are adding more side-load to the tip than you are to the tails. You do that because the tips enter the tighter section of the turn before the tails, and you do the reverse because the tails are still in that tight section when the tips are clear.
Yup...But others have been talking about adding a twist to keep the tips engaged. That is what I don't understand.
post #143 of 148
Thread Starter 
Quote:
Originally Posted by Max_501 View Post
Yup...But others have been talking about adding a twist to keep the tips engaged. That is what I don't understand.
You probably release your turn before you reach the critical angle mentioned above. Imagine if you did not release the turn, but continued to accelerate your body in a turn (albeit at larger radius) even after you have decreased the ski's tipping angle to the point where it would slip. Imagine also skiing fairly slowly with a goodly sum of angulation. Since the bindings are closer to the tails they (the tails) still have the lion's share of the weight and a nice groove to run in, and thus can still hold, but the tips will slip out. In order to prevent this you would have use pressure management to shift some weight forward. As the skis are on edge this results in some side loading. Those other poster's, no doubt, are feeling this front-biased side loading and referring to it as an extra twist, assuming they know what they are talking about.

Even if you do a nice cross-under move to a high C turn, you probably do a little of it yourself. There is no way not to do it given the ski's construction and binding position.
post #144 of 148
Quote:
Originally Posted by Ghost View Post
Even if you do a nice cross-under move to a high C turn, you probably do a little of it yourself. There is no way not to do it given the ski's construction and binding position.
I'm sure I don't add a twisting motion to the skis at any point in the turn. But I've been taught that there is so much rotary force generated passively that the last thing you need to do is add more.
post #145 of 148
Quote:
Originally Posted by Max_501 View Post
I'm sure I don't add a twisting motion to the skis at any point in the turn. . . . there is so much rotary force generated passively that the last thing you need to do is add more.
This IMO is the point that is lost to many who are skiing with technique founded on and developed from wedge and christy origins.
post #146 of 148
Thread Starter 
Quote:
Originally Posted by Max_501 View Post
I'm sure I don't add a twisting motion to the skis at any point in the turn. But I've been taught that there is so much rotary force generated passively that the last thing you need to do is add more.
Some people realize there is so much rotary force generated passively and say they are using rotary because they are aware of it, but are they really adding extra rotary? Are they referring to what you do, and call more than that over-rotating? Is it a communications breakdown or do they really add unneeded rotary force into their skiing?

No doubt some people do add in unneeded rotary, and I've seen many intermediates do it. I agree it is a possibly a very likely route to take from the flying wedge-christie. On the other hand it is also possible to quickly learn to ride the edges without unneeded rotary having learned from a severe snow-plow.
post #147 of 148
Ghost, et. all:
Here's the rub fellas. Torque and the moment of inertia are terms we use to identify and quantify a rotation around an axis. The rotation around the vertical axis happens as a function of the deflection occuring down at the snow/ski interface. Regulating the pressure along that contact patch is how we get the ski to bend into a reverse camber and it is also the key to opening or closing the radius of any turn.
How any of us choose to regulate (change) that pressure is really the debate here. Can we lever forward and use the tip as a fulcrum? Certainly! Can we add leg steering (hip articulation), or lower leg steering (articulation of the tib/fib), or foot steering (ankle)? Certainly!
The important part of this debate (at least in my opinion) is that there is no one way to create and manage the forces creating the arced ski path. In so far as the opinion that it is limited to intermediates, I for one would strongly disagree. The three skiers I learned this concept from are all current Demo teamer. The context of the clinic was dynamic medium and short radius turns. The participants were all trainer level through examiner level skiers.
The idea of discreet and independent skills is part of the problem. Isolating a skill during an exercise is an accepted path to learning more about that skill. It needs to be brought from that stage into a skiing stage before the progression is complete. Incorporating the change and blending it with other skills is the second and IMO most important part of the process.
post #148 of 148
Ghost,

Thanks for stating leg rotation as an aid to edge engagement in such a good way. Max as added his word "twist" to the ski,

Quote:
Originally Posted by Max_501
I'm sure I don't add a twisting motion to the skis at any point in the turn. But I've been taught that there is so much rotary force generated passively that the last thing you need to do is add more.
and I am thinking he is meaning pivot.

To try again to answer Max, on very hard snow (shiny ice) the edge of the ski tneds to slide off the shape of the arc after the fall line is reached, so side loading the tip espicially to keep the ski engaged instead of skidding is a must. Because the ski is on a high edge, adding front side loading is done my gently rotating the femor keeping the edge engaged and keeping the shape of the arc. I don't have any pics of me doing it, but look at a gs racer on a very hard surface after they pass the gate. The knee of the outside ski is rotated inward.

RW
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