So, an HDI gauge is also useful for something else: If there the HDI measurement yields a ROH that is larger than the true ROH at the center of the hollow, that would indicate the edge is worn down.
Edge evenness often creates edges of unequal sharpness.
In the real world, skaters measure "sharpness" in various ways that are harder to quantify. E.g.,
1. They feel the edge with their finger. Even if you don't create a foil edge, you can do that. In fact, I think it applies to almost any edged tool.
2. They skate. If they skid, or they otherwise have trouble holding an edge, it's not sharp enough.
Skating is also the ultimate way skaters use to measure edge evenness itself. E.g.,
If you skid on one edge, but not another, that may indicate edge unevenness - though that isn't the only possible cause.
If a properly aligned body weight creates skids, but an improperly aligned body does not, the edge might not be be sufficiently even. Unfortunately, that effect can also be created by nicks an edge which isn't aligned in the right direction (at the original sharpening, or by something that happened later, like a collision, or very strong stops).
BTW, some skaters adapt fairly quickly to uniformly slightly uneven edges, and may not be conscious of them. Perhaps it doesn't even matter much for those skaters, as long as they have sufficient time to adapt.
If as you roll down the blade while skating, the edge seems to push your body one way or another, that indicates a rather extreme form of varying edge unevenness. I've had that happen. Though, probably, unevenly aligned edges could do that too.
Again, if the blade skids near the center or near the ends, but not elsewhere, that might indicate the type of edge unevenness that a warped blade creates, if it was sharpened while warped. Though again, there are other possible cases.
I'm not sure if a blade could feel uneven if some parts of the blade were more sharp than others, but it is conceivable. It could certainly feel inconsistently even if the edge was aligned in one direction on one part of the blade, and another direction in another, or if our skating wore down one edge more than another.
Many of you love the idea of measuring sharpness and evenness using repeatable technical measurement methods, that can be performed in the shop, but the skater's world may be a bit different. Consistency and feel are often far more important than absolute criteria.
An edge checker is something a skater who is dissatisfied with the job a pro shop has done can bring to the pro shop to help explain why they are dissatisfied. Though, if the skater needs to do that, they should probably stay away from the pro shop altogether, or make sure they only use the best skate tech at the shop. A bad skate tech who makes uneven edges, or creates inconsistent sharpness, might do other bad things. If you need technical measurements to figure out what the skate tech is doing wrong, it is probably just best to avoid that skate tech, and maybe to assume that the whole pro shop is badly managed, and may deliver bad results in the future.
I think one of the most important things from skaters' point of view is to be able to talk to the skate tech who sharpens their blades before during and after sharpening, and to be able to give and get feedback, and understand what can and can't be done. I hated shops that kept the skater away from the skate tech, just like I hate auto repair shops where you talk to a customer rep instead of the mechanic, or you can't see what the mechanic is actually doing.
Honesty is also very important. If the skate tech pretends the blade was sharpened well, or pretends that the job done by a competitor was bad when it wasn't (extremely common - though sometimes occurs they just disagree on sharpening technique), or doesn't know the answer to a question but pretends to, that is very bad too.
It is a very good idea for a skate tech, especially one who is still perfecting their technique, to use an edge checker, or to analyze a problem a skater has told them about. It can also help a skate tech verify that their technique remains good, and some skate techs never reach the point of being able to produce good results without such tools.
It might be a good idea for a bad for a skater to use who wants to figure out why they are dissatisfied with a sharpening to use an edge checker. But edge checking isn't the whole story.
But I think skaters mostly need to pay attention to the way we feel the blade and our bodies interacting with the ice. And to treat the technical tools more as analysis teechniques than as the prime determinant. Of course, skaters who don't sharpen their blades, need to learn to be able to describe to the skate tech, things they want changed. And the shop needs to let them do that.
My conclusion: Sure, skaters should get and use simple measuring tools to check out their blades. Especially tools like this that don't cost much, are easy to carry with you, and can be applied quickly.
While you are at it, get a cheap radius gauge that lets you see if the skate tech has altered the ROH without being asked to. And trace and check the rocker profiles to see if they are changing over time - though if we don't feel a problem, maybe there isn't an important one. It would also be quite easy to use a ruler to measure the distance from the back toe pick to the point it touches on the rockered part of the blade, to feel whether the relationship of the toe pick to the rest of the blade has changed too much, making it too difficult to stay off the toe pick (there are special purpose tools for that, , but that's silly) - though that is a thing where the feel matters more than the technical measurement too.
Topic: Low-Cost Basic Even Edge Checker (Read 6260 times)