Originally Posted by bud heishman
Can the skis be brushed into a tighter turn Skiatansky?
I'm not skiantsky but I think it's an interesting question. Nerd alert ahead.
Lets for a moment disregard gravity, fricton and the fact that the body need to be turned, and just look at the turning of the skis.
Brushed carving is described as a turn where oversteering by the skis alone is providing the steering angle (1). Rate of oversteering is dependent amongs other things edge angle (2). Intuitivly it makes sense that increasing edge angle will reduce steering angle as we are traveling forward(3). If we want to keep a consistent steering angle throughout the turn, then all that is needed would be to progressively tip the skis, and when the effect of the oversteering is reduced just enough to keep a consistent steering angle, and then then resist edging more (4)
Turning radius will decrease with increased edge angles and increased steering angels up to a point. It then makes sense that different combinations of steering angle and edge angle can be combined in proportions to make the same turning radius in at turn where rate of oversteering and edging is in equilibrium to provide a consistent steering angle during the turn. Waiting longer at the top of the turn to increase edging until the desired steering angle is met will give a larger steering angle.
The braking effect will be larger with larger steering angels. The perfect offensive brush carve (5) with a slow line fast GO attitude, is then the least amount of steering angel and most amount of edging that is necessary to keep the intended round turnshape and the turning radius (6).
No but that was not the question. The question was if it was possible to decrease turning radius in a brushed carve. Do you mean compared to a carved turn? At the same speed? As for how to reduce the radius my suggestion would be:
-Increase the rate of oversteering.
-By moving more forward on the ski?
As Jamt mentionied before radius is dependent on turning force and speed:
-Reducing speed will give tighter turns, but that's not very offensive.
-Increase turning force? Increasing edging without destroying the equilibrium between the oversteering and steering angle. I guess we need to model how edge angle, turning force, turning radius, rate of oversteering, speed and steering angle all depend on each other to detitmine how fast how short it would be possible to go. And will the answer to that be very different for a skidded turn supplemented with some rotary power? We need someone to take a PhD in skidding, @Rich666 Perhaps this model exist already. Some of the relationships can be modeled easily, but not all I think...
(1) In context i think it makes sense to define it as ski angle of attack, angle between the travel direction of the ski and the direction the whole ski is pointing.
(2) Let’s keep them constant during this turn. It’s probably dependent on angulation, fore/aft balance and perhaps amount of foregonal boot pressure(?) in addition to the things that we can’t change during the turn like sidecut, taper and snow conditions. With every ting else keept the same I would think that the rate of oversteering will be much faster on ice than on semisoft untracked settled slush.
(3)This is what is happening when a large pivot is turned into a carve like the racers do. The turning radius in this segment of the turn will be really small, but it’s not possible to keep the combination of high edge angle and high steering angle throughout a turn.
(4) Well I guess stop moving sounds something does not sound like good skiing. It would also work to progressively edge more until apex and then gradually reduce edge angel. It will just provide a different turn shape or a not constant steering angle. Non of those are a goal in itself. Constant movement is probably a more important goal.
(5) I think we should stop calling it brush carve and rather star to call it “The Offensive Smear” . Not to be confused with other types of smears. Can I have that trademarked?
(6) Of course there is a limit to what kinds of turning radius and speed that will be possible.
Sorry for the footnotemania...
Edited by Smear - 11/11/15 at 11:47am