Why are the blade rocker sections uniform?

[Query]

Hockey blade rockers are near flat (9 - infinite foot radius) in the center, and becomes more curved towards the ends. The center gives strong pushes and stops; the ends create better turns. The variation is continuous, or varies in so many steps that it might as well be. I guess gradual variation gives more options and smoother stronger transitions into turns.

In contrast, most figure skating blades have two or three uniform curvatures. The main rocker portion, most of the blade, is usually 7 or 8 foot radius. The spin rocker has 1 or 2 uniform radius lengths, but less curved than for hockey blades.

Why doesn't the rocker profile of figure blades vary continuously too? I was taught to make ice dance lobes of uniform curvature, so it makes sense there - but why uniform for freestyle blades?

[Query]

I forgot to mention:

I get that moves in the fields requires uniform radius circular arcs, so a uniform curvature rocker may make that easier there too.

And the flat or nearly flat central section of a hockey blades makes for longer, faster glides. Since speed is important to freestyle skating, it might be better there too.

I realize that in freestyle, jump takeoffs and landings (and the aerial turns between) create most of the points. Do uniform main rocker and spin rocker sections help with that?

[sampaguita]

I guess it's because in hockey, you only do one thing (glide/stop). In figure skating, you have to spin and you have to glide. Spins are easiest with a smaller ROH to minimize contact with the ice, but gliding is better with a larger ROH. Also if you land jumps, you want that large contact area with the ice. These requirements may make a continuously varying rocker more difficult to engineer, so that's why it's more piecewise.

[Query]

Of course the goals of the  two sports are different, so the blades are different. But I wonder whether the rule that figure skaters use figure skating blades discourages major shape changes.

I get that jump landing stability is important, but is a uniform curvature in the entire primary rocker length really optimal for, say, vaulting into the air, or the initial heel landing?

I hope someone who knows a fair bit about freestyle skating and blade shapes will respond.

[tstop4me]

Query, you're overlooking a key practical point.  With maybe an outlier or two, sharpening machines have no control mechanism to maintain the rocker profile.  A tech guides the blade via hand and eye.  Even if rocker profiles were well controlled coming out of the factory, they wouldn't be after multiple sharpenings.  Then there's the separate issue of actual control of rocker profiles coming out of the factory. 

[Query]

...sharpening machines have no control mechanism to maintain the rocker profile... the separate issue of actual control of rocker profiles coming out of the factory.

Some of the better skate techs have bought or made guides that show the nominal original profile, for comparison.

CAG has made profiling machines for decades. Mostly for hockey skates, but some do figure skates too.

I wonder if laser cutters have improved factory profiling enough that it would matter.

But my initial question still is - are non-constant rocker sections theoretically better shapes, for a given skater? I don't know.

[Query]

I should say for me, that an easily defined rocker curve transition point (in rocker curvature and/or direction) near the ball of my foot (which I was told to call the sweet spot, though not everyone uses it the same way - e.g., see Scarlet Skater and Aimée Ricca), is an advantage, because it helps me feel when I am there.

Of course, many skate techs do gradually lose that transition point through sharpening, which I don't like. I deliberately exaggerate it.

I have also wondered if a second transition point, a little behind where the toe pick would start to engage, would help me to stay within that zone when spinning. I have also wondered wither a second transition point, near the back of the skate, would help me do backwards turns better. Some blades do add a second transition point, though I'm not sure if that is why. (Yes, I know some skaters prefer a turning technique that does not use the back of the blade.)

Freestyle skaters currently earn most of their points on jumps. Depending on where in their range of motion they are strongest, it is at least possible to imagine that some of them might vault higher in the air if the spin rocker transition was more gradual, and stronger at the end. But I'm not sure of that. Many jumps start on a turn, so perhaps it is better to have a well defined transition point??

There is already significant blade profile variation. Would it be surprising if some figure skaters would do better with some gradual transitions?