Blades by Todd Website - Rockers Explained

[FigureSpins]

Found this web page by chance and I liked the blog post about blade rockers.
http://bladesbytodd.com/rockers-explained/

The "About" section of the Blades by Todd site is like a journey for a skate technician.  Very interesting read!

[Query]

I assume he is aware that figure skating blades have at least 2 rocker radius - including the spin rocker radius(es) roughly forward of the ball of the foot.

Mike C had mentioned to me that over the years the Gold Seal changed its shape a lot. It looks like Todd took a lot of measurements. and found this to be true of a lot of blades. Perhaps this means that some coaches still advocate blade models based on out of date shapes?

I studied hollows for different disciplines of skating, including a special ‘Patch’ sharpening technique that would fool the judges.

What would "fool the judges", and in what respect?

[Loops]

Awesome find!  So interesting.  Thanks for sharing.

[AlbaNY]

Interesting read!

[Kaitsu]

I would be also very interesting to hear what a special ‘Patch’ sharpening technique means. I have heard and seen several times "butcher sharpening´s", where skate tech is fooling everyone, including him/her selves, but Patch sharpening is totally new term to me. The given tips where it is said to fool judges does not help me to understand what is actually done for the blades. I believe it is related how blades sounds when you are skating. At least its common topic that judges does not like how certain blades sounds.

What comes to the different rockers radius's, I am quite confident when I claim that 99.5% of skaters has not verified what the rocker radius they actually have in their blades. They believe to skate with certain rocker radius which is informed by manufacturer, but reality is very often something else. Laser cutting is not securing correct radius in the final product as there is so many manual grinding phases and induction hardening after the laser cutting. Most likely manufacturers tries to make cutting so that errors on the upcoming phases are pre-compensated, but there is a lot of unknown variables before blades are put in to the box. I am also 99% sure that there is no any quality control that rocker radius in the final product would be that what has been promised. It would be too expensive to check every blade and scrapping rate would be huge...except if you have huge tolerance.

I am also a bit skeptic if people can really recognize differences example between 8 or 9 foots radiuses. If you take a look attached sketch, you will see how small area of the 8 or 9 foot radius is actually used in the blade. As we use so short distance from the very large circle, also "the height" differences are very small...or at least they look very small in the sketch. Maybe I need to use my router to produce wooden off-ice "spinners" to test the differences in the practice. Wooden spinner could be also interesting challenge for Bill which is real handy man and owns lots of nice tools. I am sure he would have skills to produce such a spinners. As he is also skater, he would be more experienced to say if he feels any differences between them.

[Bill_S]

Patch skating is where skaters do school figures on a "patch" of ice assigned to them.

Patch blades have a minimal toe pick (especially the drag pick closest to the ice) to reduce the chance that a skater would accidentally hit it while doing figures. Drag picks were often ground to reduce their size for this kind of skating.

The blades also had a very shallow ROH for maximum glide for any given push. Common ROH values for patch blades would be around 3/4" to 1".

I completely agree that the stated rocker on blades can be substantially different than specified by the manufacturer. I've measured the rocker on enough new blades to draw that conclusion.

An experienced skater can tell the difference when switching between a 7' rocker and a larger 8' rocker. When I experimented with different blades a few years back, I could sense differences between them. However, I became accustomed to any new rocker size within a few hours of skating. The hardest part was adjusting to different spin rockers for, well..., spinning.

Here's another (animated) illustration that I created showing the small difference between a 7' and an 8' rocker. Click to enlarge.