Is my understanding of ROH correct?

[Christy]

I currently have a 1/2" ROH on my matrix elites and I'm having several issues with spinning and stroking - I find the blade doesn't glide as well as my old matrix legacies.
I'm tall and heavy so I'm thinking that changing the ROH to 3/8ths will help. Is that correct or should I be changing to 5/8ths?

[Bill_S]

Going to a small radius ROH will slow you down, not improve glide. I have experienced that when switching between 1/2 and 3/8 ROH.

I've been using 3/8" and it's very "grippy". I just purchased a new 1/2" stone to try for more speed, flow, and glide. Of course the tradeoff could be less grip in deep edges (leaned over).

EDIT: Replaced vague terms. Thanks jbruced!

[rd350]

This is an interesting thread.  My last sharpening Jim did 1/2" and I had difficulty with it.  He went to 7/16" and I was much happier, but have/had no clue why!

[Bill_S]

The best sharpener/fitter in my region uses 7/16". It's halfway between 1/2" and 3/8".

I assume that it's a good compromise for most skaters.

Speed skates are sharpened dead flat across the blade, yet the skaters manage to do some really impressive edges (leans).



It makes me think that there are some other factors beside ROH to make a blade grip well while providing speed. It also makes a case for shallow ROH providing good speed and glide (less friction).

[jbruced]

Going to a shallow ROH will slow you down, not improve glide. I have experienced that when switching between 1/2 and 3/8 ROH.

I've been using 3/8" and it's very "grippy". I just purchased a new 1/2" stone to go back up for more speed, flow, and glide. Of course the tradeoff could be less grip in deep edges (leaned over).

Bill_S I think the use of the word shallow may be a little confusing in this case. A 3/8" radius is smaller than a 1/2" radius but creates a deeper groove or hollow in the blade. I think smaller would be a better word in this sentence.

Please accept my humblest apologies in advance as I realize my comment comes across as obnoxious or rude and that is certainly not my intent. I completely understood what you meant and agree with the point you were making. The use of deeper and shallower in relation to the measurements was confusing to me when I first wrapped my head around the ROH concept. I see the same confusion with others when we discuss ROH at the rink.

[Christy]

I had read that 7/16" was a popular option so may try that. Need to check what I had on the Legacies.

Hmmm, now wondering if you should keep the same ROH when changing blades i.e. is the ROH independent of the blade?

[Query]

My understanding is that a flatter blade (greater radius of hollow) is faster. E.g., a speed skating blade has no hollow, and also has much less rocker curvature.

As near as I can tell, a flat blade skims over the surface. A sharper edge, created in part by a smaller ROH, cuts into the surface more, which should give one cleaner edges and perhaps better spin and jump entries.

However, this is complicated by the fact that the edge of the pushing foot must bite into surface to give you a good strong push, so that the gliding foot can go further. Good skaters, especially good freestyle skaters, don't push as much as they "flow". Instead of pushing somewhat backwards with one foot, they use a more sophisticated pressure-against-an-edge technique to create more speed. I don't fully understand the advanced technique, but I would assume you need a fairly sharp edge to do that too.

So there is a trade-off between good glide and good push.

This is my current understanding.

[lutefisk]

I'm happy with 1/2" ROH.  Plenty grippy for me.  I'm 5'9" tall and weigh 175 lbs.  I've come to the conclusion that most of my skating problems are related to the skater and not the equipment.  Axel Paulsen didn't have anything near the equipment we have today, yet his name will be remembered forever...

[irenar5]

I'm happy with 1/2" ROH.  Plenty grippy for me.  I'm 5'9" tall and weigh 175 lbs.  I've come to the conclusion that most of my skating problems are related to the skater and not the equipment.  Axel Paulsen didn't have anything near the equipment we have today, yet his name will be remembered forever...

Amen!   My coach sharpens her blades once a year (if that), never wears guards and gets an amazing edge rip and body lean with plenty of speed. 

[Bill_S]

Bill_S I think the use of the word shallow may be a little confusing in this case. A 3/8" radius is smaller than a 1/2" radius but creates a deeper groove or hollow in the blade. I think smaller would be a better word in this sentence.

Please accept my humblest apologies in advance as I realize my comment comes across as obnoxious or rude and that is certainly not my intent. I completely understood what you meant and agree with the point you were making. The use of deeper and shallower in relation to the measurements was confusing to me when I first wrapped my head around the ROH concept. I see the same confusion with others when we discuss ROH at the rink.

Oh, my yes! Thanks for the observation!

I don't have any emotional attachment to the terms at all, and thanks for identifying that the term "shallow" could be seen two ways - a shallow radius vs shallow hollow. I'm all for clarity, so I'll be more specific in the future.

I edited the original post to use less vague terms.

[Query]

Speed skates are sharpened dead flat across the blade, yet the skaters manage to do some really impressive edges (leans).

Beautiful picture. Can you do that? I simply cannot place myself in such a lean while gliding. I'm told that touching the hand to the ice like that slows you down a little, and they try to avoid it, though they do balance very close to the tipping point.

Also, note that they produce an extremely sharp edge - a right angle (90 degree) edge, that is usually sharpened at least once / race day. A normal figure skating hollow produces an edge angle only slightly smaller than 90 degrees. Also note that some speed skaters produce an over-burr (see this discussion), a thin edge extension, perhaps 0.001" or less [?] wide, which protrudes into the ice, which seems to me to create a more effective edge than a deburred hollow ground figure skating edge, though it is more fragile.

This data is based on the observations of two speed skaters, both of who have coached local speed skating clubs, and both of whom have taught sharpening techniques. If you go on-line, you will find many opinions of exactly how speed skating edges should be ground - they don't all agree on all details, but they care a lot.

Speed skaters are not judged on edge quality - some speed skaters can glide sideways, though not as fast. A figure skater who skidded around lobes like that might lose points, no matter how deep the lean.

[Doubletoe]

There are a number of factors that could be contributing to the lack of glide.  It could be that you just got a sharpening that was a little off this time.  It could also be that the ice is harder than it was before, due to seasonally colder temperatures.  The harder the ice, the harder you need to push and the drier it tends to be once the water has frozen after the ice resurfacing.  A smaller/deeper ROH is recommended if you are going to be skating regularly on hard ice.

Also, is the issue actually glide on your spin entries, or is it the ability to hold an edge?  If it's lack of glide--i.e., the blades are too grippy, then you might try going to a larger/flatter ROH (maybe 9/16"?).  If the blades aren't cutting into the ice enough for you to get a good push and hold your edge, then you might want to re-sharpen them, and if that doesn't help, go to a smaller/deeper ROH (maybe 7/16"?).

[Christy]

The temperatures here have fluctuated wildly so we've had a very wide variety of ice, and the type of ice has definitely had an impact on gliding / stroking. I'd say I've had more problems when the ice has been soft. Over the next few months I expect the temperatures to stay colder so the ice to be harder.

The spin problems could be a result of changing the blade length and trying to find the sweet spot / get used to it being in a different position on my foot.

[aussieskater]

I understand that speed skate blades are very flat (think 8 metres or more compared to our 8 feet or less!).  Given that, they must have more actual blade on the ice at any one time.  Could this be a factor in holding them on those wicked leans?

[Query]

Different speed skaters choose different rockers, just like us.

And maybe we are all "off our rockers".

I do know that a lot of speed skaters undergo a strengthening and conditioning program, perhaps partly so they can hold those body positions. I don't know what else is involved in holding that position. But even for us, is a big psychological element to trusting ourselves on deep outside edges. Just watch a class of LTS students learning outside edges or crossovers. Most really, really do not want to be on those outside edges. I used to think I was on outside edges when I really wasn't.

Do you think the bend at the waist affects balance and the ability to hold that position?

Anyway speed skating is kind of off-topic.

Also, is the issue actually glide on your spin entries, or is it the ability to hold an edge?

I know the latter affects me. As I enter a scratch spin, I do initially change to an inside edge during the 3-turn, but I usually lose the depth of that edge, sometimes even rock all the way to the outside again, and I often keeping rocking back and forth all over the place and my spins travel. (Note: in theory, if you hold your balance position constant, you will glide on an arc of constant radius, which means the foot will glide around a small circle, and your spin won't travel. It sounds so simple to say it, yet can be so hard.) I can't figure out why I can't hold that inside edge! I seem to have a psychological unwillingness to push my foot to the outside enough to leave my upper body weight leaned over the inside of that arc, which defies any and all rational analysis. I.E., I keep trying to balance my weight vertically over top of the foot, even though objectively I know that is wrong, instead of leaning to the inside.

I have no idea whether that is the original poster's issue. But it is one of mine.

[Doubletoe]

The temperatures here have fluctuated wildly so we've had a very wide variety of ice, and the type of ice has definitely had an impact on gliding / stroking. I'd say I've had more problems when the ice has been soft. Over the next few months I expect the temperatures to stay colder so the ice to be harder.

The spin problems could be a result of changing the blade length and trying to find the sweet spot / get used to it being in a different position on my foot.

Hmm, if the issue is glide and it's worse when the ice is soft, maybe your ROH is too deep (small), making your blades feel too sharp.  Interesting about the blade length.  Are your new blades shorter or longer than the old ones?  Another thing I just thought of is that your old blades were flatter than the new ones by the time you switched blades, simply by virtue of having been sharpened many times and losing a little of the rocker with each sharpening.  The longer the blade and the flatter the blade, the better glide you get (which is why speed skate blades are so long and flat).

[Christy]

Hmm, if the issue is glide and it's worse when the ice is soft, maybe your ROH is too deep (small), making your blades feel too sharp.  Interesting about the blade length.  Are your new blades shorter or longer than the old ones?  Another thing I just thought of is that your old blades were flatter than the new ones by the time you switched blades, simply by virtue of having been sharpened many times and losing a little of the rocker with each sharpening.  The longer the blade and the flatter the blade, the better glide you get (which is why speed skate blades are so long and flat).

Chatting to my sharpener we concluded that it was a combination of a slightly too deep ROH and the ice variations as a result of the constantly changing weather that was causing the glide issues, whilst the spinning is a combination of a shorter blade plus different rocker location. So, blades have been sharpened / adjusted, but I can't test the theories for two weeks :-(

[Christy]

Surprise opportunity to skate - 7/16ths rocks   

[Doubletoe]

Surprise opportunity to skate - 7/16ths rocks   

Great to hear!   So you went from 1/2" to 7/16" ROH?  That would technically be "deeper" since an arc from a smaller circle could fit deeper into the space between your edges than the arc of a larger circle.  This should be giving your edges more "bite" into the ice, which helps you hold your edges better on harder ice.  http://img.photobucket.com/albums/v111/timmyh911/skatehollowvisual-1.jpg

[Christy]

Hmmmm, interesting. The ice is definitely harder than it was when I had the 1/2" sharpening, but I'm finding I have less bite with 7/16". One issue I have noticed, and it might be more to do with the straight cut picks on the Elite, is that I've had the odd slip on jump landings for the first time in around 2 years 

[Doubletoe]

Hmmmm, interesting. The ice is definitely harder than it was when I had the 1/2" sharpening, but I'm finding I have less bite with 7/16". One issue I have noticed, and it might be more to do with the straight cut picks on the Elite, is that I've had the odd slip on jump landings for the first time in around 2 years 

More than the straight cut toe picks, I would think it might be the rounder rocker on your new blades that could cause a slip on your jump landings.  When you go from a flattened out rocker to a new, round rocker, you need to point your toes hard on landing to make sure the pick contacts the ice before the ball of the blade does.  Then you need to push your heel down so you don't stay on the ball of the blade.  When the rocker is flattened out, the ball of the blade isn't "in the way" like that on your jump landings.

[Query]

Ice hardness can make a big difference.

But, if your blade is aligned right, and you and your clothing and equipment weight at least 100 pounds, it's basically impossible for you to skid. 7/16" or 1/2" ROH are good enough. So something IS wrong.

Are you using a new sharpening pro, or are you taking more steps on the mats off-ice? The tip of the edge may be slightly bent over, or the new sharpener may be handling the sharpening burr a little different. Or maybe he slightly dulls (rounds off) the edges after creating them.

These differences can be too small to see, yet can make a huge difference in your skating. You have to tell by feel, or by how you skate.

Feel the sides of the blade near the bottom. Don't run your finger along the blade - you might cut yourself. Just tap it lightly at many points. If anything is rough or sticks out by feel on the sides, something is very strongly protruding bent over, and is really messing you up. All the sharpness should be on the bottom of the blade, not the sides.

Also - let the edge glide without weight against your fingernail (or if you like your fingernails, a piece of wood). It should very easily slice off a layer, if it is sharp. That has nothing to do with hollow - only how sudden the direction changes are - which is in many ways a more important form of sharpness than hollow.

Many people carry a small flat stone - say 800 - 1000 grit, or even finer, which they use to straighten edges that have bent a bit outwards. I sometimes have also carried a piece of hard leather that I first used to push the edges out a tiny bit, so if the edge was bent inwards, it would be fixed. After straightening the edge, do not take a single step off ice. Sometimes this makes a huge difference in your skating, even when you can't feel anything by the methods I mentioned above.

[irenar5]

But, if your blade is aligned right, and you and your clothing and equipment weight at least 100 pounds, it's basically impossible for you to skid. 7/16" or 1/2" ROH are good enough. So something IS wrong.

You can skid any time if your weight is not over the edge. Hockey or show stops are a purposeful skid.  Not being on a correct spot on a three turn is an unintentional skid.

[Query]

if your blade is aligned right, and you and your clothing and equipment weight at least 100 pounds, it's basically impossible for you to skid. 7/16" or 1/2" ROH are good enough.

You can skid any time if your weight is not over the edge. Hockey or show stops are a purposeful skid.  Not being on a correct spot on a three turn is an unintentional skid.

More precisely, you can skid if weight plus inertial forces (e.g., centrifugal force, jump landings) isn't aligned through the blade edge. But she was talking a jump landing - in which case, if I was taught right, her weight plus inertial forces should be aligned through the blade edge - because you don't want the edge to skid.

The other time you can skid is if the blade isn't aligned along the main motion - e.g., pretty much all stops, deliberately skidded jump take-offs, or severely under- or over- rotated jump landings.

So in either case, the skid occurs only if she was aligned what I was thinking about as "wrong".

But yes - for those moves that are supposed to skid, my "wrong" alignment is "right".   

And now that I think of it, I think many jumps where you land forward onto the toe pick might briefly skid forward on that toe pick. (I still don't understand why it is "good" to land on the toe pick when you are landing forward. It creates a jerk in the skater's motion which seems ungraceful.)

So I generalized way too much. Shame on me.

[Christy]

Ice hardness can make a big difference.

But, if your blade is aligned right, and you and your clothing and equipment weight at least 100 pounds, it's basically impossible for you to skid. 7/16" or 1/2" ROH are good enough. So something IS wrong.

Are you using a new sharpening pro, or are you taking more steps on the mats off-ice? The tip of the edge may be slightly bent over, or the new sharpener may be handling the sharpening burr a little different. Or maybe he slightly dulls (rounds off) the edges after creating them.

These differences can be too small to see, yet can make a huge difference in your skating. You have to tell by feel, or by how you skate.

Feel the sides of the blade near the bottom. Don't run your finger along the blade - you might cut yourself. Just tap it lightly at many points. If anything is rough or sticks out by feel on the sides, something is very strongly protruding bent over, and is really messing you up. All the sharpness should be on the bottom of the blade, not the sides.

Also - let the edge glide without weight against your fingernail (or if you like your fingernails, a piece of wood). It should very easily slice off a layer, if it is sharp. That has nothing to do with hollow - only how sudden the direction changes are - which is in many ways a more important form of sharpness than hollow.

Many people carry a small flat stone - say 800 - 1000 grit, or even finer, which they use to straighten edges that have bent a bit outwards. I sometimes have also carried a piece of hard leather that I first used to push the edges out a tiny bit, so if the edge was bent inwards, it would be fixed. After straightening the edge, do not take a single step off ice. Sometimes this makes a huge difference in your skating, even when you can't feel anything by the methods I mentioned above.

I definitely exceed the 100lbs, have the same sharpener, and do take a couple of steps on the rubber matting when I get off the ice to re-tie my skates but I did that more prior to the recent sharpening because I was breaking the boots in. I have felt the blades as you describe and don't notice anything obvious. I think I used to have one of those stones that you mention - need to search through my old stuff and see if I can find it.

My landings are still a bit "off" sometimes, but not exactly skidding so I do wonder if it's the different location of the toe pick and something I just need to get used to?