How Do I Turn?

[Stephen]

@tkarhu, these guys are actually going fast enough to put enough pressure on the skis to really carve turns (although there is also skidding):

[GrimSurfer]

these guys are actually going fast enough to put enough pressure on the skis to really carve turns (although there is also skidding):

Maybe I don’t understand you… are you actually saying that speed is required in order to put enough pressure on your skis as a prerequisite to starting a turn?

Because that’s how your statement reads to me… and it makes zero sense whatsoever.

So maybe I’m not understanding you correctly. Mplesse clarify what you actually meant.

[GrimSurfer]

these guys are actually going fast enough to put enough pressure on the skis to really carve turns (although there is also skidding):

Maybe I don’t understand you… are you actually saying that speed is required in order to put enough pressure on your skis as a prerequisite to starting a turn?

Because that’s how your statement reads to me… and it makes zero sense whatsoever.

So maybe I’m not understanding you correctly. Please clarify what you actually meant.

[Stephen]

No speed required. I can just stand here and ski down the hill. I have some special goggles I put on and I’m Peekaboo Street, just zipping down the Super G course.

[GrimSurfer]

No speed required. I can just stand here and ski down the hill. I have some special goggles I put on and I’m Peekaboo Street, just zipping down the Super G course.

Your statement made a connection between speed and pressure before turn initiation.

What is that connection, exactly? I want to know… because this trick has somehow eluded me up to now. Knowing more might help me be a better skier.

Lord knows, I can use all the help I can get.

[Stephen]

OK, I’ll quit being snarky.

But it seems obvious.
And, you’ll have to put up with me not knowing the correct terminology to use.
Let’s say: turn left.
Skier tips skis on edge to engage inside (left) edges of skis.
Skis have sidecut so bend as the tip and tail support the ski more than the waist (because of side cut).
Skis are now curved into an arc with more or less equal pressure along the length of the ski.
The faster the skier is traveling, the more energy is required to change direction, which produces more pressure applied to ski, whic requires more edging to resist skidding, which bends the ski more, which makes the ski turn.
The faster the speed / the greater the course direction change, the greater the pressure applied to the ski to resist skidding, the greater the bend, …

The limits are the ability of the ski to cut through the snow and follow an arc (“carve”), rather than skid out (like tire traction), the speed potential of the skis and slope, the strength of the skier, the ultimate flex and flex pattern of the skis.

Possibly I’ve skipped a step, or misused a term, or oversimplified in some way which would trip me up here, but I think I have laid out the basic concept.

And this is why tip pressure was a hot topic, because additional tip pressure (beyond a neutral stance over the center of the ski) forces the front of the ski to bend more, enhancing the ability of the ski / skier to turn more quickly or more sharply.

OTOH, if one is skiing very slowly and tips a ski with sidecut on edge, if the ski is reasonably stiff, as most skis are, there will not be enough energy to bend the ski. This is probably why most skiers use skidded turns — because they work at low speeds.
This is a real hurdle for those learning to ski: most people don’t want to go faster because they don’t know what to do or what’s going to happen next, so never build up enough energy to make the skis do their thing.
I think this is really true with the narrow, double camber skis.
It takes some energy to get those skis to turn.

Anyone who wants to add, subtract, refute, confirm, or clarify, feel free.

[GrimSurfer]

Weighting your heel on the lead ski definately helps in carving, not sure why though. One reason may be that when you put weight on your heel you may also be flexing your ankle forward which would give you better edge control.

I would imagine (and this is pure conjecture based on how I visualize what’s happening under my feet), that weighting your heel in the lead ski does two things:

1. It takes pressure off the front of the ski, making it less resistant to turning (grip is proportional to load, all other things being equal); and

2. It places greater force on the back half of the ski, which leads to a lower polar moment of inertia (this is a fancy term that means it’s less resistant to any forces that would lead to a change in direction).

I suspect that both these things allow better edge control. The front and rear edges bite differently, which helps the turn.

This is just what comes off the top of my head (could be other, better, explanations) because the lead ski seems pretty important in executing a successful telemark turn.

[lowangle al]

Weighting your heel on the lead ski definately helps in carving, not sure why though. One reason may be that when you put weight on your heel you may also be flexing your ankle forward which would give you better edge control.

I would imagine (and this is pure conjecture based on how I visualize what’s happening under my feet), that weighting your heel in the lead ski does two things:

1. It takes pressure off the front of the ski, making it less resistant to turning (grip is proportional to load, all other things being equal); and

2. It places greater force on the back half of the ski, which leads to a lower polar moment of inertia (this is a fancy term that means it’s less resistant to any forces that would lead to a change in direction).

I suspect that both these things allow better edge control. The front and rear edges bite differently, which helps the turn.

This is just what comes off the top of my head (could be other, better, explanations) because the lead ski seems pretty important in executing a successful telemark turn.

It does take pressure off the front of the ski, but that's not my goal. You are just carving with more pressure on your tails than tips.

On #2 you may be on to something because the ski does feel resistant to directional change. Add to this that when your heel goes down, your toe goes up, now you have a flexed ankle too.

Weighting the heel of your lead ski works best on turns close to the fall line. If you want to cross the fall line at bigger angles you will want to pressure the lead ski with a flat foot and drive a knee over that foot to get more weight towards the tip. This enables you to get more edge earlier in the turn. This is something that comes in real handy on steep terrain to control speed.

[Stephen]

But, I should point out that in what I wrote above viewtopic.php?f=1&t=4436&start=90#p54876 is in reference to the part of the video that showed Telemark Ski Racing.
And, specifically about the skier’s ability to CARVE turns.
Good ski racers have years of practice learning to do one thing really well: Carve turns.
Carved turns maintain more speed than skidded turns (that’s why they are less useful for controlling speed).
So, to win races, be good at making carved turns (among other things, of course).

@Montana St Alum looks like he can carve a pretty mean turn.
Me, I try, but not so much.

The reality is that, especially on narrow, double camber skis, mostly skidded turns are most common, or a combination of skid/carve.

But, unless the turn is pure skid, a bent ski still helps the turn.
And, the ski needs to be on edge to some degree to keep from just sliding sideways and not turning.
Any ski with sidecut, put on edge, will bend into an arc.

If you have a flat wood surface long enough, put the a ski on it, tip the ski maybe 30* to 45* on edge, apply pressure to the middle of the ski (from the top side), and the ski will bend into an arc.
Ski manufactures use the geometry of the ski and sidecut to calculate the arc a ski will travel when it is bent like that.
I think if the skier wants a tighter turn than that arc radius, some degree of skidding is involved.

[lowangle al]

Stephen, as far as carving goes, if your dbl camber skis passed the paper test, they aren't going to carve well on hard pack, that's one reason they skid. Add a few inches of fresh and they suddenly work.