Originally Posted by eleeski
@freeski919 I will stand by my base assumptions. I watched my skis and the skis of the instructors - I didn't see much bending. That's what started this whole activity.
The fault lies in you powers of observations - a 180 cm ski with 2 cm of bend (that is, if the center of the ski was flat on the ground, each tip would be 2 cm off the ground) would carve a turn with a 20.26 meter radius. Not exactly a super tight turn, but we're talking instructional free skiing, not pure carving race skiing. (By the way, I'm not deriding your powers of observation - the amount of bend that was present during your observations is likely to be impossible for anybody to accurately observe and judge.)
I also have confidence in my ability to engineer a stiff ski. Gonzo stiffness (what I was shooting for) is much easier than a smooth blended flex (in a nicely behaved ski). I did a bit more than glue a block of wood on the ski (I thought I mentioned the graphite unitdirectional that capped the wood). The skis were stiff enough that they did not bottom out the camber on a level floor (OK there was a huge amount of camber to start with).
Does that mean that the camber was reduced by some amount, even if very small?
How does a skate turn? Sure, on a molecular level there is skidding going on.
Because they bend, and they have have rocker, and some even a parabolic sidecut. Just like skis. Except the bend is even harder to see with the naked eye. Here's an explanation from a speed-skate manufacturer, Bont.
"People have been trying to come up with a parabolic blade since bending blades first became accepted as the norm in short track speed skating. Short track skaters have always sacrificed their straightaways for the corner. The parabolic having a curve on both sides of the blade like a carve snow ski lets you turn around the corner without sacrificing your left foot push on the straight."
But it sure feels like a carve when my rollerblades follow a not too wide circle. While a curved snow ski edge might make certain radius carved turns easier, the range of carveable arcs is not limited solely by edge curvature. Something else is going on.
There is, but only slightly - the sidecut of the ski. In soft snow, the tips and center of the ski can all touch the snow surface at the same time, when minimally tipped to engage just one edge, effectively producing an arc equal to the sidecut radius. But with 40 or 50 mm difference between tip and center width, bending is required to engage tips, tails and centers in order to carve a tighter turn. So yes, a bit of a turn is possible with no bending at all, due to sidecut, but only at much larger radii than a bent ski can achieve.
On the Sochi thread, Tog posted a bunch of pictures of racers. Most of those shots showed little ski bending. I sure seemed to me that when the skiers were going fast and smooth the skis weren't bent. Am I to ignore those photos?
When watching video of ski racing, it's obvious the skis are flopping all over the place. I suspect that the pictures showing the skis straight are at times during those flops when they are straight, hopping off the ground, or the like. Which is why I suggested a slow-mo video. Check out Lindsey Vonn in slow-mo SL. Go to 45 seconds. You'll see that when she initiates her turn, her skis bend. When she has minimal to zero contact with the snow is when her skis are straight and there's no snow being kicked up.
The explanations do make sense. Trying to get my skis to bend was a great coaching tip. It felt right. But my skis weren't actually bending.
1) Yes they were. You just couldn't see it happening.
2) There weren't bending and you were simply turning at the sidecut radius. The Salomon BBR you mention, for example, in 177 mm length, has a 20 meter sidecut radius, like the 2cm setup I mentioned above. On softer snow that allows for both the tips and the center of the ski to contact the snow without the ski bending, it is indeed possible to carve a turn with just sidecut alone, no bending, if you minimally tip the skis so that just one edge is engaged.
Read the 8th post here http://snowheads.com/ski-forum/viewtopic.php?t=72074 with the side cut radius and carve zone diagrams for another explanation. Minimal carving can be achieved with no bend due to sidecut. Any tighter carving requires bending.
Then "experienced" people say my stiff cambered skis won't carve. It felt like they did carve. And how does a funky shape like the Salomon BBR be so much fun to ski? Reality is not matching the explanations.
Rather, your observations aren't matching reality. Or, you and everybody else are talking about different things - sidecut radius vs bending due to sidecut.
While my expertise is in waterski design, construction and performance, I have confidence in my ability to test and feel characteristics in snow skis. Besides, "I'm the best skier on the mountain!" GNAR.
I am sorry if I offended anyone. I don't recall calling anyone silly or stupid - if I did I apologize. I won't apologize for questioning accepted beliefs when I see contradictions.