Je voulais savoir quel roh vous pratiquez dans vos pays?
cela fait 3 ans que j'affute et je vais vous dire les roh que je pratique:
5.5/16 :pour les confirmés, poids normal, pour les sauts simple et double , pour la danse solo niveau national
6/16: pour ceux qui ont un niveau moyen et qui commance à patiner avec un coté de la lame( carre)
6.5/16: pour les débutants, adultes et les patineurs un peu costaud
Je me demande s'ils ne se sont pas habitué à cela ...
quand j'essaie de chercher, je trouve pas grand chose si ce n'est que le roh classique est 1/2 pouce.
Et je me demande si je ne fais pas trop creux....
un ancien patineur de notre club qui faisait les triples saut faisait encore plus creux que 5.5/16 alors que moi je trouve que c'est déjà tres creux!!
Alors je voulais avoir un peu vos avis...
Bien à vous tous dans vos différents pays et merci de m'eclairer un petit peu
There is no single standard.
I believe studies have shown that the most common hockey ROH in NHL (The major professional league in Canada and Mexico) is 1/2". But the online advice has been that it should depend on the skater's weight and aggressiveness. E.g., a lighter skater, or one who isn't very aggressive skater needs sharper blades, which is taken to mean a lower ROH. The variation with weight and aggressiveness makes sense for figure skaters too.
And I think that most people I know stay with the ROH the blade comes from the factory with - at least on factory pre-sharpened blades. That usually means 7/16" for most figure skating blades, but 3/8" for MK Dance (because it is ground "thinline" - thinner at the bottom of the blade).
But Mike C told me that many people in New York City used 1/4". And for some reason a lot of the hand tool sharpeners available cheap from China are that.
And the few people I've known who did school figures - which is now similar to what is called "skating skills" in the U.S., want longer glides, so they sometimes choose 3/4" or even 1".
I'm not sure if it makes sense to use a different ROH on synthetic (lubricated plastic) ice. Edges wear out so fast that maybe people choose higher ROH??
The best skate techs I've known give the skater what they ask for. Or they try to copy what the skater already has.
Most skate techs remove the sharpening burr, by using a flat stone, slanted slightly inwards towards the centerline of the hollow. That makes the blade less sharp, and the amount of it you use might vary. Coarse grain wheels and stones also produce a less sharp edge than fine grain wheels and stones. And the rocker length affects effective sharpness too. So ROH isn't the only factor in sharpness.
Also, some blades are said to have a dovetail shape - meaning that the sides of the blade near the bottom slant inwards, which means that the angle included between the hollow surface and the sides is less. In theory, that would let you use a longer ROH to get the same angle.
The speed skaters and Nordic ice skaters I've talked to about this say they don't use hollow.
RoH for hockey players:
A general rule used in Europe to find a suitable radius of hollow (in mm) for adult ice hockey players, is to divide the body weight (in kg) with π (3.14).
Example: if your weight would be 80kg = 80kg /3.14 = 25mm (1").
Hockey players in the US and Canada are generally skating on a smaller RoH than Europeans.
Though, there are by now enough examples in the NHL of players using a very high RoH. Paul Coffey, Mark Messier, Matt Cullen and Sergei Gonchar being some of the most famous ones.
25mm (1") and above may sound extreme, but these players are so good at skating that it is their preference to maximize their glide and speed at the expense of bite.
My advice is: go for the shallowest hollow you feel comfortable with.
The choice of RoH is always a compromise.
With hollows such as 13mm (½ ") the edges are always biting.
The more flatter the hollow becomes the more edge control you have to apply.
At RoH 19 (¾ ") it becomes scary for most of the skaters to change skidding into controlled sliding.
From 25 (1") onwards it's all about good edge control.
You have to try it out to know how much speed and less fatigue you can gain at the expense of bite.
Keep in mind it might take a few skating sessions to utilize the benefits of flatter hollows.
Wally, Skater and Skate Sharpener
Back in NY the hockey players I sharpened for basically always wanted 1/2". I can't really remember anyone asking for another hollow.
I'm still trying to figure out the number system in Germany. They just ask hockey or figure skater and only have those two options. I don't get sharpenings done here and haven't gotten a mini job yet so I can't say more. I believe I used to get 17 in Romania?
I saw a video once (from Blademaster's) that said there were differences between hockey in the U.S. and Europe.
In particular, in the U.S., most hockey is played on NHL size rinks, whereas in Europe, they said it was more often played on larger Olympic size rinks.
Blademaster's video said that meant the central portion of the blade should have a flatter rocker - in fact that many players wanted no rocker curvature in the middle, presumably because the larger rink let people go faster, and they could stop and change directions faster.
I don't know if that would also affect ROH.
But if it does, then a difference in rink sizes could perhaps affect figure skating too.
Even in the U.S., many figure skaters prefer to practice on Olympic size rinks - but most skating facilities don't have them. :(
Obviously, if a skate tech has to change ROH more often, they wear down their grinding wheel and their dressing tool more rapidly, and they also have to spend time doing so - time they could be earning money by doing more sharpenings. Even if they use different wheels for different ROH, they have to spend time changing wheels. So some skate techs (or their pro shops) try to settle on one ROH. Or push everyone to be willing to use one ROH. Some charge more for other than their preferred ROH.
Also, some people feel the ROH should depend on the temperature of the ice. E.g., many rinks set up to be best for hockey keep their ice colder (and harder) than rinks more optimized for figure skating. I was told rinks optimized for curling takes warmer ice than either.
When I sometimes had to skate on outdoor ice, which sometimes creates a lot of very rough ice, and variation in surface conditions, I kept my blades extra sharp, so I could cut through to get a better surface.
Perhaps there are also variations for humidity? Because a lot of humidity produces rougher ice too.
So not everyone will agree on what ROH should be. So a skate tech who is willing to give skaters what they want might be able to charge more - but might have to spend more time and supplies doing that.
I started on 1/2" but moved to 7/16" a long time ago - and because I felt like I wasn't getting enough grip.
Most blades are designed with a 7/16" recommendation, so it also made it easy from that end, as well.
It's kind of the default ROH for a lot of techs (when the skater doesn't specify anything differently) when sharpening free skating blades.
Radius of Hollow for figure skates
Skate sharpeners are supposed to advise the skaters and help them to find the best RoH for their kind of skating.
But this is hardly the case. This is what usually happens:
• The skater does not have contact with the sharpener
• The sharpener does not ask which RoH the skater wants and applies the "house cut" which is usually 13mm (½")
With deeper cuts the edges are wearing out faster than with shallower cuts.
• The sharpener is not a skater and cannot give tailored advice.
Fortunately, some sharpeners do have the knowledge and experience to advise the skater (figure, hockey, freestyle, recreational).
There are 4 main levels of skaters:
1. Beginners
2. Intermediate
3. Advanced
4. Expert
Advanced and expert skaters can skate on any cut and the choice of RoH becomes a personal preference influenced by body weight, personal style, age, level of edge control, ...
Beginners and intermediate skaters can use some help by means of a flatter hollow between 19mm (¾") and 25mm (1").
The principle of RoH for beginners is simple:
The deeper the hollow, the more the skates control the skater.
The shallower the hollow, the more the skater controls the skates.
People these days are generally skating on a too deep hollow (figures and hockeys alike). The better your edge control, the shallower the hollow can be.
Good edge control makes your body adaptive enough to do those turns without the need for a deep hollow. If you are good enough, you never need those deep cuts. You will be able to cut those corners with the extra advantage of more glide.
Good luck to all beginners skating on hard hockey ice during the winter up here with a 1" hollow.
The ice up here gets too hard in the Winter for that to be generally viable - especially for beginners who are not as adept in skates.
There are a couple of rinks here with better great control (comfortable on the ice, even in winter) and ice temperature maintained for figure skaters (usually on the Olympic surface - though one is the opposite :-P), but that is more of an exception. Lots of skaters skate at multiple rinks, so they generally sharpen for the more problematic scenario they deal with.
Flatter blades on hard ice are more problematic than sharper blades on soft ice, so that is what the skates are sharpened for.
That's generally how I approach this, as well. It's why I moved from 1/2" to 7/16".
Skater Body Composition and the Ice they skate on have to factor into this, as well.
Merci à tous,
je lis avec attention toute vos réponses.
ce que savais c'était que les patineurs de vitesse ont des patins tout plats dessous c'est à dire vraiment à l'equerre.
Je sais aussi que moins c'est creux plus on va vite mais pour faire de la danse ou des figure cela accroche moins!
Mais avez vous déjà affuter des patins à des patineurs qui font des triple saut ....et etes vous sur qu'il ne faudrait pas se rapprocher du 5.5/16 6/16 ?
Je vous rapelle pour certains que je me suis mis à affuter pour ma fille, et que moi hélas je ne patine pas!!!
Il est très compliqué de trouver de vraies réferences dans le sud de la France, et l'affutage est un monde très secret....
Donc par vos réponses , je penserais faire un petit moins creux et descendre donc dans mes 3 catégories :
1 compétitions
2confirmés
3 débutant / recreatifs
I'm basing this on "Google Translate", because I don't know French.
>What I knew was that speed skaters have skates that are completely flat
>underneath, meaning they're square.
Not flat: Most, speed skaters I've known sharpen their own skates and create a "foil edge". That means they polish and redirect the sharpening burr to extend down into the ice. The foil edge is very thin, and is much sharp than a hollow grind, so you can push better, but is still very fast. But it is also very fragile - they sharpen every time they race.
I used to sharpen my figure skates with a foil edge, but not now, because the edge doesn't last as long.
I watched a world class skate tech work, including for people doing triples and quads. He tried to get them all to use 7/16".
Sometimes he dulled the front 1/3 of the outside edge on the jumping foot, to make it 1/1000" shorter, for skaters who needed to skid into double jumps (but non-skidded jumps are "better").
But that is just one skate tech.
Blademaster says:
https://blademaster.com/pages/skate-sharpening-101
Wissota says (for hockey?):
https://wissota.com/support/skate-sharpening-101/choose-your-radius
They both make skater weight a major factor, not skill.
Quote from: R45 on March 11, 2025, 06:44:07 AMAdvanced and expert skaters can skate on any cut and the choice of RoH becomes a personal preference influenced by body weight, personal style, age, level of edge control, ...
Beginners and intermediate skaters can use some help by means of a flatter hollow between 19mm (¾") and 25mm (1").
The principle of RoH for beginners is simple:
The deeper the hollow, the more the skates control the skater.
The shallower the hollow, the more the skater controls the skates.
People these days are generally skating on a too deep hollow (figures and hockeys alike). The better your edge control, the shallower the hollow can be.
Good edge control makes your body adaptive enough to do those turns without the need for a deep hollow. If you are good enough, you never need those deep cuts. You will be able to cut those corners with the extra advantage of more glide.
You've got this backwards. Advanced and expert figure skaters can benefit from the extra glide of a larger ROH for maneuvers that call for extra glide, because they have developed advanced edge control to press the edge into the ice harder (to get greater bite) when they need deep edges. Beginner and intermediate skaters have yet to develop such advanced edge control; hence, they need the assist of a smaller ROH (greater bite) to attain deep edges, at the expense of less glide during maneuvers not requiring deep edges. If you start beginners on a 3/4" to 1" ROH, they never will develop advanced edge control: they will spend the majority of their time skidding, going kersplat, and sitting on the ice. They are better off starting with 7/16" or 1/2" for a more controlled bite initially and then increasing ROH as their edge control improves.
For 3 years I offer skate sharpening in Singapore.
First sharpening is for free as well as any new RoH they want to try.
I do this because sharpening is a hobby for me, and I love to see the progress of the skaters. I am skating myself and can see what happens when they try out different radii.
With deeper hollows there is more friction to overcome and that's the struggle for beginners because they don't have the speed and the skills. For them it feels like being a train on the tracks.
A larger RoH (19 till 25mm) is more easy for them and also allows them to sense how a proper edge should feel, and at the same time be forgiving in things like T-stops and hockey stops.
This is confirmed by the experience of the skaters using different radii.
The skaters are a mix of hockeys, figures and recreational skates.
Advanced figure skaters are a small group only, there are no expert skaters, and they prefer radii between 13mm and 19mm (½" and ¾").
Advanced freestylers on hockey skates perform best on RoH 25mm to 32mm (1" to 1¼").
So - a conclusion might be that people can't agree on what ROH is best. Much like other sports equipment decisions. :D
Quote from: Query on March 14, 2025, 10:11:49 AMSo - a conclusion might be that people can't agree on what ROH is best. Much like other sports equipment decisions. :D
Ultimately, there's not one single best value of ROH (or other parameters) for every skater. There's a whole host of variables involved, and ultimately it's a matter of personal preference (skaters need to try out different values and see what they like best; and this may change over time). And advanced skaters are more adaptable than beginner skaters. The major issue that I see is what range of ROH (or other parameters) various people recommend for beginners, who don't know any better, and are not yet in a position to experiment and find their optimal values, because they're still struggling with basics such as balance and positioning of various body parts.
Quote from: tstop4me on March 15, 2025, 09:03:49 AMThe major issue that I see is what range of ROH (or other parameters) various people recommend for beginners, who don't know any better, and are not yet in a position to experiment and find their optimal values, because they're still struggling with basics such as balance and positioning of various body parts.
That's correct, I only give beginners a different hollow when the are ready for it.
Like discussed earlier in another thread, we should talk bite angles instead of ROH. Then we would speak "same langue". Like already pointed out by others, same ROH will give different bite angle if the blade thicknesses varies. This should be noted example if you change from Coronation Ace to Coronation Ace lite.
Unfortunately it is not so simple that blade thickness would be the only thing in blades which is affect to the bite feeling. My favorite topic is this &#¤%&" chrome removal grinding where they basically ruin the blades, if nowhere else. These specific blades has now 7mm ROH, since 5/16" was not deep enough and I can expect that problems still continues until she changes blades. I already have challenges to dress the wheel to enough small ROH.
https://youtu.be/bBdq03asRpI
Very cool video!
I had assumed the reverse would be true - that the chrome removal would be done using a complex grinding wheel, giving one a slight dovetail shape, that would slightly decrease the included angle (of bite).
I wonder how typical this is for new HD Sports blades.
The video is a little bit mean to HD Sports. No matter how well you do something, it is always possible to do better. They aren't a precision machine shop, creating parts to a .0001 inch precision, and charging thousands of dollars or more per blade to do it. They are creating a relatively crude tool to cut into the ice so it doesn't slip sideways. Perhaps their prices could be lower - but people continue to buy from them in large quantities.
Of course, many (most?) skate techs use a flat stone to round off the edge itself as well, to get rid of any sharpening burr that might be formed. That also affects effective sharpness a huge amount - but doesn't change the bite angle.
Plus that type of flat stone use would create exactly the shape that the video shows, because the stone is usually tilted slightly inwards towards the center of the hollow. Is it possible that was how that shape was created, rather than the chrome removal process? And if so, we don't know whether that reshaping was done at the factory, or at a pro shop.
Alternately, some skate techs, especially those using fine grain grinding wheels, and some people using hand tools, push the sharpening burr vertically, to create a much sharper blade than the bite angle would indicate - unless you count the near-zero bite angle at the end of the created foil edge.
And I believe, but haven't proved (because my microscope isn't that good) that most sharpenings create a ragged edge, sort of like a saw blade (but less regular) that might also dig deeper, and therefore act more sharp.
Also, I think much of the time, possibly most of the time, when people think they need a sharpening, they could instead just straighten the edge.
In other words, bite angle is but one of many factors in effective sharpness. Important, but not always the most important.
And without more information, we don't know whether the inward tilt that the video shows was created at the factory, or at a pro shop.
Query,
Here is a brandnew Gold Seal blades and quote from HD-sport confirmation.
https://youtu.be/HATMLP8SbOw?si=DW_UbyaXaEXbTQOu
The characteristic you have described are a result of a part of the process which make the blade what it is-- heralded around the world.
The blades in question meet our current production standards and do not indicate a fault or deviation.
Sigh.
Chrome removal (or "Chrome Relief", as Sid Broadbent called it) doesn't have to ruin the blade. In fact, I think it is desirable, if the chrome plating isn't nearly as hard as the steel. Because if the plating remains, the plating could flake off, or perhaps wear down in an uneven fashion.
But you have successfully proven that the chrome removal was done in a very puzzling fashion, on that blade. What is more, the bite angle will change abruptly, when the sharpening goes past the rolled edge - and if the metal isn't taken off uniformly, it will be change abruptly along the length of the blade.
I'm not a machinist. I think I understand how they create the concave portion - I think they used a cylindrical shaped grinding tool, sort of like a cross grinding sharpening tool, but applied to the sides. If I understand correctly, that is somewhat common on some types of expensive knife. And it makes some sense on skating blades. Can you help me understand what tool creates a rolled edge like that? Is there any reason for them to use that tool?
E.g., is the rolled edge a consequence of the cutting tool (a laser?) that cuts the profile (and if so, why?), but they positioned the grinding tool too far up on the blade?
BTW, perhaps you want to rewrite "what they were still in 90 century" in that video. That's a bit unclear. Did you mean something like "That's the way it was done in the 20th century"? (And is that true?)
HD Sports must hate that many people are becoming aware of these issues through forums like this! If they aren't careful, more and more people will "herald" their mistakes rather than their performance, and will switch brands...
What do you believe very good skate techs should do with blades like that? If you returned them, would the next pair be any better?
BTW, by "bite angle", do you mean the "included angle" between the side of the blade and the hollow?
Wait!
I just figured out a way rolled off edges could be created:
Many (most?) skate techs and skaters feel that the potential sharpening burr (which as far as I can tell, only actually forms if you use a fine grain grinding wheel) should be removed. So they slide a flat stone along the sides after sharpening, pointed slightly inwards. I wonder if HD Sports does that, or something equivalent, at the factory.
But my understanding was that people who advocate that, try to remove very little steel. Ideally, I think they just want to remove the burr, and maybe make the final edge a little less sharp, because many skaters don't like ultrasharp edges. In that case, burr removal would leave most of the dovetail shape in place (NOT what they did, according to your video), to reduce the included angle, and to reduce the deepness of edge the skater needs to skate on to create clean arc lines on the ice, for a given included angle. (I.E., you can also reduce the included angle by using a smaller ROH - but that means you need to skate on deeper edges to make them clean. If you reduce the angle by using a dovetail shape, that isn't needed.)
Whether the effect is by rolling off the edge, or by burr removal, if it removes that much steel, as you note, it completely destroys the purposes of that type of side honing, that most people think they are trying to achieve - unless the entire purpose is to remove a tiny fraction of the weight from the blade. Could that tiny amount of weight matter?
Quote from: Query on May 25, 2025, 11:04:50 PMHD Sports must hate that many people are becoming aware of these issues through forums like this! If they aren't careful, more and more people will "herald" their mistakes rather than their performance, and will switch brands...
We've had blades manufactured to tighter tolerances using licensed profiles for decades. I think JW/MK have great marketing by putting top skaters on their blades and advertising it. That is going to make it hard for any competitors to topple them - regardless of the relative merits of the products.
Not meaning to sound harsh, but this market is rooted in a massive amount of ignorance. Skaters and parents of skaters often don't know the technicalities of the equipment they are purchasing/using. They simply go with the recommendation of the professionals that they know and trust - or defer to what other top skaters are using as a guide.
It's like the thing about how Edeas can't over boot a skater. Forums are the only place where I see people argue against this. Didn't stop one parent from getting Ice Flies and Gold Seals for an 8 year old... and I was shocked that they even manufactured those blades in that size.
The amount of people reading forums is really inconsequential when juxtaposed against the size of the overall market; and advocating against this can feel rude. I just don't generally do it, nor do I make it my business to educate people. If the Pro Shop won't say anything, then I guess that's on them. I don't want to run the risk of them thinking I'm impeding their business if word gets back to them that I told Suzie or John to buy a cheaper pair or boots or a lower level blade, Lol.
Our discussions are going heavily out of the original topic. Marc I am sorry about that.
Nate, Could you tell us whom is this "We" whom has manufactured JW/Mk profiles with tighter tolerances for decades?
I know that Paramount claims that they make blades with JW/MK profiles, but their profiles tolerances I am not so sure. Definitely they do not make rolled edges, but their profiles accuracy is a bit question mark. This is what they wrote to me some year ago. See also attached photo from their C9
blade.
"We are not a skate sharpening company. We only send 5 or 6 pair a year that are sharpened, we do not do the sharpening."
"The accuracy only comes on the SS blades, SS blades only. You get what you pay for. Cost a lot to machine the profiles."
Both Ultima and Paramount have been well known for doing profiles more accurately than HD Sports (MK & JW). I have many pairs of runners of the old Ultima Matrix (I) blades, all of nominally 9-3/4" size. Within each model, I could not visually tell the two blades in a pair apart, laying them on top of each other. That included many Ultima Dance pairs - and I couldn't visually tell any of them apart that way.
But I recently looked at the left and right blades of a new pair of Jackson Ultima Freestyle skates (which the dealer said he had not sharpened) that included Ultima Aspire XP blades (admittedly not their highest end blades!). I traced them. When I tried to match the left blade against the tracing of the right blade, and tried to precisely match the fronts (spin rockers) of the blades (which did match pretty well), the backs were different by 1 or 2 mm. So their profiles aren't very similar either. But perhaps their higher end blades match better. Or maybe that one pair was unusually bad?
Quote from: Nate on May 26, 2025, 12:07:51 PMNot meaning to sound harsh, but this market is rooted in a massive amount of ignorance.
Of course, most markets are. :)
E.g., most of us don't understand everything there is to know about cars, houses, computers, cell phones, clothing etc. in enough detail to make really good judgements about them.
Yet people often have very strong preferences about them, which don't always reflect engineering quality measures.
OTOH, I suppose you could argue that in a sport like figure skating, where you can win or lose based on tiny performance details, we ought to care more about these kinds of issues, which might impact performance.
Quote from: Kaitsu on May 31, 2025, 12:01:09 AMI know that Paramount claims that they make blades with JW/MK profiles, but their profiles tolerances I am not so sure. Definitely they do not make rolled edges, but their profiles accuracy is a bit question mark. This is what they wrote to me some year ago. See also attached photo from their C9
blade.
"We are not a skate sharpening company. We only send 5 or 6 pair a year that are sharpened, we do not do the sharpening."
"The accuracy only comes on the SS blades, SS blades only. You get what you pay for. Cost a lot to machine the profiles."
Thanks for this response from Paramount. Though it's a bit bizarre, given their marketing hype on their website:
"Not only are Paramount Sk8s fully customization, they are also perfectly leveled and balanced from the most advanced sharpening method the market has ever seen, revolutionizing the way we sharpen blades."
Even on their top grade 440C stainless-steel blades, though, the finish of their factory-sharpened edges is not that great. I still have my tech sharpen them first. I have no means to determine profiling accuracy though.
Paramount 17" Blades are the same as my MK Phantoms in terms of profile, but their tolerances are lower so you're getting something true to the schematic... This can feel a little different than actual MK Profiles machined to higher tolerances.
The only differences are:
1. They are lighter
2. They hold sharpening much longer (420SS)
3. They are not tapered (due to design/construction)
Cost difference isn't huge with their SS blades, unless you catch a pair of Phantoms on super sale, but if you want to shed weight, the difference is very noticeable when you mount them onto lightweight boots. Paramount isn't as annoying as Revolution when it comes to grabbing the blade, etc.
I rate their customer service very highly. Feels very "mom-and-pop" compared to other FS equipment manufacturers.
You only get factory grind on the blades when they send them out. You need to have a tech sharpen them when they come in. Edges may not be even, etc.
Personally, I find the 420SS a bit ... aggressive. They hold edges too long and the blades feel like they're controlling me because of how much bite they have. Would probably switch to a shallower setting if I were to skate on them full time. Maybe 1/2". I felt like I was going to catch and edge and wipe out stopping all the time with them. They do make edge jump entrances feel stable, though.
The toe rake on the Paramounts are a little bigger/more aggressive than MK's, and they aren't coated so they are very sharp.
The aluminum runner scratches easily. I don't think I'd get anything but Polished as far as color goes. Anything else will start to look ugly pretty quickly from your blades hitting each other and whatnot.
I have never purchased paramount carbon. That is something they added later to have products at a lower price point. Sometimes things like that picture posted happen. I've gotten SS blades that had markings like that on the side. Has something to do with the part not being placed properly in the machine. They simply sent a return receipt back and made a new pair of blades and sent them out to me quickly. Was pretty painless.
If you get something like that, just send them a picture and they'll almost certainly replace the blades ASAP at no cost to you. They are pretty easy to deal with - even if you purchased from a reseller.
Hi Marc,
If those numbers you quote are sixteenths of an inch e.g. 6/16" which equals 3/8", those are very unusual numbers. Are you sure you are speaking about radii and not diameters?
For hockey players in the US and Canada, the most common roh are 1/2" or 5/8" for players and something like 1" for goalies (because they need to slide their feet out quickly to get their leg pads flat on the ice for blocking shots). And these edges are actually not as sharp as figure skaters with the same hollows because their blades are much thinner.
For figure skaters, the far majority of blades come from the factory with 7/16" and most skaters stick with that number. Even members in our club doing triples and attempting quads use the same radius. And 3/8" is realistically not usable by most skaters due to them having almost no glide at all (unless the ice is like -20C or something).
For beginner and less advanced skaters, coaches usually recommend something much less deep; anywhere from 1/2" to 5/8". The reason is that these skaters have most problems maintaining glides, and learning T-stops and the shallower radius is a big help. Also, they need to learn to attain edges with their bodies and not just use sharp edges as a crutch.
And a shallow radius is not that limiting as I know skaters that can do doubles with 5/8".
Hope this helps!
Quote from: marc on March 09, 2025, 02:01:30 PMJe voulais savoir quel roh vous pratiquez dans vos pays?
cela fait 3 ans que j'affute et je vais vous dire les roh que je pratique:
5.5/16 :pour les confirmés, poids normal, pour les sauts simple et double , pour la danse solo niveau national
6/16: pour ceux qui ont un niveau moyen et qui commance à patiner avec un coté de la lame( carre)
6.5/16: pour les débutants, adultes et les patineurs un peu costaud
Je me demande s'ils ne se sont pas habitué à cela ...
quand j'essaie de chercher, je trouve pas grand chose si ce n'est que le roh classique est 1/2 pouce.
Et je me demande si je ne fais pas trop creux....
un ancien patineur de notre club qui faisait les triples saut faisait encore plus creux que 5.5/16 alors que moi je trouve que c'est déjà tres creux!!
Alors je voulais avoir un peu vos avis...
Bien à vous tous dans vos différents pays et merci de m'eclairer un petit peu
Those Dance blades that are ground thin at the bottom ("thinline", like MK Dance) often have smaller radius. At one point, I believe they published 3/8" ROH as the factory grind. And here is a website (from the main US distribute of Edea boots) listing 5/16" for MK Dance:
https://skatesus.com/product/mk-dance-figure-skating-blade/
However, because they are thinner at the bottom, the small ROH does not create as small an included angle as it would on a wider blade, such as a typical freestyle blade.
However, Eclipse Dance blades are also nominally thinline, but they recommend 1" ROH.
I have used 3/8" ROH on various blades, including freestyle blades, for a long time. But I would like to try a larger ROH, on the assumption that they would glide better. I think I originally benefited from that small an ROH because I was not aligning my weight with the direction of the blade very well. Also, because I sometimes skated on relatively cold (hockey) ice. And maybe I wasn't strong enough yet to push down hard on the blades.
BTW sometimes skate techs choose relatively small ROH for very light skaters - e.g., little kids, especially if they aren't very aggressive skaters, because without that, the kids don't get much ice penetration.
Hi query, nicelce,
J'écris en français depuis mon téléphone !
Merci pour vos échanges constructifs.
Cela me fait réfléchir et avancer et depuis le début de cette discussion j'affute moins creux.
Je vais vers 7/16 pour les compétitions, et je vais essayer le 1/2" pour les débutants (petits et adultes).
J'ai essayé le hockey :
3/8 pour un enfant 8ans
Et
6,5" pour son père ( cela fait 30 ans qui fait du hockey et il trouve que cela lui va bien)
Mais je vais essayer,sans leur dire, de baisser de roh à tout les 2 et je pense qu'il verront rien.
A suivre ...
I don't think you should change the ROH without telling them!
If a skate tech had done that to me, I would never have gone back to them, and I would have told all my friends to stay far, far away from that skate tech.
You could get a very bad reputation if you do that. And in my opinion you would deserve the bad reputation.
Also, you use up a lot of blade metal, and therefore reduce blade lifetime, when you change ROH.
The responsible thing to do would be to ask for permission first, saying that you think they would benefit from the change - but only if you really do think they would benefit.
I'm not sure what you meant by 6.5". At least in the U.S.A., " is an abbreviation for "inch". Did you mean 6.5 mm? If so, both of the current ROHs are fairly reasonable for a child and an adult.
Quote from: Query on September 03, 2025, 03:32:41 PMI'm not sure what you meant by 6.5". At least in the U.S.A., " is an abbreviation for "inch". Did you mean 6.5 mm? If so, both of the current ROHs are fairly reasonable for a child and an adult.
If you check the original post (beginning of thread), marc initially specified values of ROH in increments of 1/16". So 6,5" was a typo; should have been 6,5/16", where some countries use a comma instead of a period as a decimal-point separator.
Quote from: NiceIce on August 23, 2025, 11:20:37 PMIf those numbers you quote are sixteenths of an inch e.g. 6/16" which equals 3/8", those are very unusual numbers. Are you sure you are speaking about radii and not diameters?
Quote from: NiceIce on August 23, 2025, 11:20:37 PMFor figure skaters, the far majority of blades come from the factory with 7/16" and most skaters stick with that number. Even members in our club doing triples and attempting quads use the same radius. And 3/8" is realistically not usable by most skaters due to them having almost no glide at all (unless the ice is like -20C or something).
For beginner and less advanced skaters, coaches usually recommend something much less deep; anywhere from 1/2" to 5/8". The reason is that these skaters have most problems maintaining glides, and learning T-stops and the shallower radius is a big help. Also, they need to learn to attain edges with their bodies and not just use sharp edges as a crutch.
And a shallow radius is not that limiting as I know skaters that can do doubles with 5/8".
* I'm in the US. I skate in indoor rinks. The ice temperature never gets as low as -20 deg C (-4 deg F). I'm medium weight (135 lbs), not super-lightweight. I specify a 3/8" ROH on my freestyle blades (confirmed by gauges). I further hand burnish the edges to be really sharp. I have no problems with glides and T-stops. I prefer the extra bite for deep edges entering a spin.
* As I wrote previously, large values of ROH (say 5/8" or greater) are advantageous for advanced skaters since they can benefit from the extra glide on maneuvers that do not require a deep edge. At the same time, when they do need a deep edge, they have enough control to press the edge into the ice. One advanced skater I know (jumps triples; amazing spins; swooping spirals down the length of the ice) at one time used a 1" ROH. Another sharpener recommended that she change to 3/4". An ex-US-national pairs champion (also an ex-Olympian) goes to the same sharpener that I do. She specifies 5/8" ROH.
* But beginners have not attained good edge control. With large values of ROH, they will skid on many single-edge maneuvers. Several of the sharpeners in my area use a default of 1/2" ROH if the skaters don't know what to specify. When beginners discuss their skidding issues with me and ask for my advice, I will recommend 7/16" ROH; so far, they've been happier afterwards.
Quote from: marc on September 03, 2025, 06:51:33 AMHi query, nicelce,
J'écris en français depuis mon téléphone !
Merci pour vos échanges constructifs.
Cela me fait réfléchir et avancer et depuis le début de cette discussion j'affute moins creux.
Je vais vers 7/16 pour les compétitions, et je vais essayer le 1/2" pour les débutants (petits et adultes).
J'ai essayé le hockey :
3/8 pour un enfant 8ans
Et
6,5" pour son père ( cela fait 30 ans qui fait du hockey et il trouve que cela lui va bien)
Mais je vais essayer,sans leur dire, de baisser de roh à tout les 2 et je pense qu'il verront rien.
A suivre ...
Hi marc. I never learned French, so I'm working off Google translate. As you can tell from the various responses, there is no consensus on the optimal value (or range of values) for ROH. There are many variables, and different approaches to skating. Ultimately, it's a matter of personal preference once the skater has advanced sufficiently. So I agree with Query (not something I often do ;D ), that you should not secretly change a value of ROH. You can recommend a default value for a beginner who has no clue; and you can suggest a change for a more experienced skater who has requested a particular value. If they agree, then all is good. But if they do not agree, then don't make any changes.
-20 deg C (-4 F)? Yuk!
Does arctic scuba diving sound fun too? :o
Query
You're right, for both hockey players, I wouldn't change ROH without telling them.
The skaters in my club have complete confidence in me, and rightly so. If I sharpen, it's because my daughter is the strongest in the club, and I wanted the best for her.
And she's my biggest test.
She was used to 5.5/16, and I wanted to go 6/16, but she was scared until the day she agreed and didn't notice any difference... (and yet she skates a lot, 10 hours a week!!)
And then I bought her Matrix Supreme blades (where they recommend 7/16), so I sharpened them to 7/16.
And then I realized that these blades were the best: more speed in a straight line and great grip in turns with a less hollow edge!
My wife, too, for whom I gave a test:
5.5/16 even though she's just a beginner and a bit strong (but it was my first sharpening attempt),
and recently, I went up to 7/16 and, of course, she sinks less into the ice and brakes better.
So to all those beginner skaters whose skates I sharpened last year in 6.5/16, I'm going to warn them that I'm going to go a little less hollow in 7/16