By John Harmata
What happens when a skater can no longer spin correctly or has difficultly with jump take offs and landings? The usual comment is that the blade has lost the rocker or its original profile, which is most commonly 7 or 8 foot.
Let’s take a moment to talk about the number; 7 or 8 foot as an example. What would you say if I said there is more than one rocker to a blade and that in many cases it doesn’t even come close to 7 or 8 foot?
Let’s dissect a blade and see. First we need to understand how blades get their profile, the positioning of it on the blade and how it is lost over time.
1. Achieving blade profile – Almost all blade profiles are now created using CAD drawings (computer assisted drawings), which are very accurate. The drawings are fed into a computer assisted laser cutting machine where they are cut out accordingly – again very accurate.
2. The placement of the profile/rocker is extremely important because this is where the spin point is established. Some blades will have the profile curve a bit further up to the front of the toe picks, while others will have it placed back a bit. Either placement is fine, but this is not the 7 or 8 foot rocker that blade radius is based upon. The remaining curvature behind this point is that which is labeled 7 or 8 foot. Long story short………it doesn’t matter if your blade is marked 7, 8, or whatever, because you are not spinning on the back part of the blade. Skaters spin on the front curvature, which is quite different than the rest of the blade. To show you some of the differences, refer to the drawing guide.
Once the front curvature of the blade is removed (after several sharpenings), spins and jumps become more difficult. So you see, having a 7 or 8 foot rocker is irrelevant. What matters more, which is never addressed is the accuracy of the blade edge from front to back and the amount of edge bit you get from a blade made using modern day technology instead of those from outdated manufacturing methods.
What makes the difference is the accuracy of the drawing and what is done to the blades after they have been cut out.
Have a great skater everyone………
– Guest author, John Harmata, askmredge.com