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On the Ice => The Pro Shop => Topic started by: Leif on December 06, 2017, 02:36:36 AM

Title: CW crossovers and foot sliding
Post by: Leif on December 06, 2017, 02:36:36 AM
I'm trying to improve my clockwise forwards crossovers but my right foot (the inside one) slides to the left. A friend who is a very good skater watched me and confirmed that the blade slid on the ice. I have tried bending my knees more, and leaning more to no avail. Does anyone have ideas? My friend tried too, and his right foot did not slide, although he has a 3/8" hollow and I use 5/8". I noticed that my edges are both out by 4 thousandths of an inch according to my BAT gauge. Also the ice was very hard, though my skates were sharpened a week and a bit ago, and I've done maybe 10 hours skating since. I use Step steel which is a higher grade than the standard Bauer blade. Oh yes, I wear hockey skates too!

Curiously this does not happen when I skate backwards, both CW and ACW crossovers.
Title: Re: CW crossovers and foot sliding
Post by: tstop4me on December 06, 2017, 07:38:54 AM
I'm trying to improve my clockwise forwards crossovers but my right foot (the inside one) slides to the left. A friend who is a very good skater watched me and confirmed that the blade slid on the ice. I have tried bending my knees more, and leaning more to no avail. Does anyone have ideas? My friend tried too, and his right foot did not slide, although he has a 3/8" hollow and I use 5/8". I noticed that my edges are both out by 4 thousandths of an inch according to my BAT gauge. Also the ice was very hard, though my skates were sharpened a week and a bit ago, and I've done maybe 10 hours skating since. I use Step steel which is a higher grade than the standard Bauer blade. Oh yes, I wear hockey skates too!

Curiously this does not happen when I skate backwards, both CW and ACW crossovers.
Let's see, if you are doing clockwise forward crossovers, then your right foot should be on an outside edge.  So the first thing to check is how are you doing on your right forward outside (RFO) edge.  First, test it out from a stationary T position:  right foot in front, left foot in back, crossed in a T position, push onto a RFO edge.  Can you hold it?  Next, test it out from a moving circular position.  Get up some speed.  Go two-footed on a CW circle.  Lift the left foot and place it next to or behind your right foot.  Lean onto a RFO edge.  Can you hold it?

I'm not a hockey player.  But when I was checking into radius-of-hollow (ROH) details, my understanding was that goalies often use a large ROH (such as 5/8" or larger), but regular players typically use a smaller ROH.  In particular, hockey steel tends to be thinner than figure skate blades, and a smaller ROH is needed to achieve appropriate edge angles.  What is the thickness of your steel (measured across the flat sides of the steel)?  Why did you choose such a large ROH?
Title: Re: CW crossovers and foot sliding
Post by: Leif on December 06, 2017, 08:27:02 AM
Thanks for the reply. I can do a tight turn CW quite easily, going on deep edges ie. right foot on outside, left foot on inside with me leaning quite sharply and turning on a 2m radius (better skaters can do tighter). However my weight does tend to be on the rear of the skates in a tight turn. I was feeling my edges as I did CW crossovers, and tried to make sure my right foot got the outside edge correctly.

Yes I can do outside edges i.e. skate in a curve on one leg such that I am riding an outside edge. I can do that on each leg, and did it last night, it's one of my standard drills I practice, along with forward crossrolls/scissors. I do find the 'grip' on the ice depends strongly on the quality of the ice surface i.e. smooth or rough.

Regarding RoH, yes hockey skates are thinner, about 3mm. Many hockey skaters choose 5/8" as it gives speed and good sliding. I find 3/8" far too deep and I cannot skate on it. 1/2" is okay, but I prefer 5/8". Some say 1/2" is 'standard' for hockey skates, some say 5/8" is 'standard'. Generally shallow hollows are better for beginners as it takes less effort. And of course it depends on one's weight and the ice (hard or soft). I'm just over 11 stone (154 British pounds). And the ice at the local rink is hard. Interesting idea though, that I might need a deeper RoH.
Title: Re: CW crossovers and foot sliding
Post by: Bill_S on December 06, 2017, 08:40:28 AM
I was going to suggest knee bend, but I see that you have experimented with that.

You could experiment with a deeper ROH like your friend has, but I'd still work on deeper knee bend. Stiff legs are among the top reasons for skidding.

The fact that it happens to you during a CW crossover (I would guess that's not your favored direction) makes me suspect that there's something in your technique that is different from your other direction. And I'd guess that even more knee bend is needed.

All that will come with practice.
Title: Re: CW crossovers and foot sliding
Post by: Mirabelka on December 06, 2017, 09:58:59 AM
I have similar problem with my left foot when skating CCW forward crossovers. My left foot slides to the right. I think the reason is the way I bend the left ankle too much to the right side when putting the foot on the ice.
Title: Re: CW crossovers and foot sliding
Post by: tstop4me on December 06, 2017, 12:29:49 PM
I noticed that my edges are both out by 4 thousandths of an inch according to my BAT gauge.
Forgot to ask you about this.  If I recall from one of your previous posts, your BAT gauge measures the angle by which your edges are off level.  If you know the thickness of your blade, you can calculate how much higher one edge is than the other.  But it does not measure depth of hollow (DOH).  So when you say that "my edges are both out by 4 thousandths of an inch", do you mean on both blades, one edge is 0.004" higher than the other?  If so, which edge (outside or inside) is higher on your left and right blades?  If you are in fact talking about edge height discrepancy, 0.004" is too much, and indicative of poor sharpening.
Title: Re: CW crossovers and foot sliding
Post by: Query on December 06, 2017, 02:54:35 PM
.004" would be a really, really poor sharpening. Even .001" is an awful lot, that creates major problems.

But as I mentioned here (http://skatingforums.com/index.php?topic=7906.msg94653#msg94653), a blade mounted with a tilt can also create skids. If you invert the skate, does the blade stick up at exactly a right angle to the bottom of the skate? A tilted blade acts a lot like using the wrong edge lean. Any tilt that you can see with your eye is extreme.

Nonetheless, as I also mentioned there, you can't always blame skating problems on the equipment.
Title: Re: CW crossovers and foot sliding
Post by: Leif on December 07, 2017, 04:18:57 AM
Thanks all, some good replies there. I will try standing still and sliding the right foot outside edge, and see if there is an issue with the edge itself. I always assume it is my technique rather than the skates, unless proved otherwise. I have seen the same issue with two sets of runners, so it's not the runners that are at fault. We shall see. I will try bending my knees even more, and try and compare my CW and ACW crossovers, to see if there is some difference.

Yes the error in the edges is the difference in height of the edges i.e. one edge is 4/1000" higher than the other when the blade is held vertically. I know 4/1000" is bad, but it is very rare for me to get a sharpen within 1/1000". I've checked numerous other peoples skates and none are as good as 1/1000".

I am toying with the idea of getting a sharpening machine. The ProSharp Home is pricey, but it looks like the only way I can get a good sharpening without having to hand them in to a known good person and wait a week for them to come back. Maybe I should get a second pair of skates.  :o I do like my skates to have a good edge.
Title: Re: CW crossovers and foot sliding
Post by: tstop4me on December 07, 2017, 07:35:42 AM
Thanks all, some good replies there. I will try standing still and sliding the right foot outside edge, and see if there is an issue with the edge itself. I always assume it is my technique rather than the skates, unless proved otherwise. I have seen the same issue with two sets of runners, so it's not the runners that are at fault. We shall see. I will try bending my knees even more, and try and compare my CW and ACW crossovers, to see if there is some difference.

Yes the error in the edges is the difference in height of the edges i.e. one edge is 4/1000" higher than the other when the blade is held vertically. I know 4/1000" is bad, but it is very rare for me to get a sharpen within 1/1000". I've checked numerous other peoples skates and none are as good as 1/1000".

I am toying with the idea of getting a sharpening machine. The ProSharp Home is pricey, but it looks like the only way I can get a good sharpening without having to hand them in to a known good person and wait a week for them to come back. Maybe I should get a second pair of skates.  :o I do like my skates to have a good edge.
Your combination of a thin blade and shallow hollow calls for very careful sharpening.  Under ideal conditions, a blade thickness of 3 mm and a radius of hollow (ROH) of 5/8" would result in a depth of hollow (DOH) of only .003"; so you see, an edge height difference of .004" is way out of wack.

I wouldn't get hung up in trying to get edge height differences less than .001", though.  Such tight tolerances are difficult to achieve with a skate blade (long, thin geometry) and skate sharpener (hand guided); particularly, when the final operation involves hand finishing with a whetstone.  Furthermore, to measure such tight tolerances, you need the right instruments, and you need to know how to use them properly (e.g., clean off dust particles and avoid excessive pressures during measurement).  I have a hollow depth indicator (HDI) which directly measures depth of hollow and edge height discrepancy to better than .001" (graduations are in .001" increments, can estimate readily to nearest .0005").  After a sharpening, I do multiple measurements along both blades.  With two good sharpeners in my area, only on rare instance do I get less than .001" edge height discrepancy; more commonly about .001", with excursions to .002".  But note that these are with thicker figure skate blades (.15 - .16") and smaller ROH (7/16 - 3/8").

What's peculiar though, is that with your edges, I would expect you to notice a significant difference in feel between outside and inside edges just when skating on a circle (without cross-overs).  But that doesn't appear to be the case for you.

By the way, the Sparx website indicates that their machine is now in general release (at least in the US, not sure about the UK); so check that out again.
Title: Re: CW crossovers and foot sliding
Post by: Leif on December 07, 2017, 08:25:58 AM
Thanks again, interesting stuff. Sadly the Sparx is not available outside North America.

I did the depth calculation, and got it wrong the first time. Hohum. Yes, you're right, about 3/1000" is the depth! Eeek. 4/1000" is way out of whack.
Title: Re: CW crossovers and foot sliding
Post by: Query on December 10, 2017, 01:01:03 AM
Try measuring the height difference at several places along the blade. See if you get consistent results.

If, OTOH, you get one edge higher in the center, and the other edge higher at the ends, that would suggest you have a warped blade, and a sharpener who lacks the proper means to straighten it, at least while sharpening.

I've never heard before of anyone viewing .001" edge height difference as insignificant. For example, when a good skate tech wants to create a "skid" point on a blade (to make it easier to do skidded jumps, or, for hockey goalies, to make it easier to slide on the back of the blade from side to side, they might lower the appropriate part of the outside edge or edges by about .001". It's enough to make an enormous difference - so say two very good skate techs, who specialize, respectively, in figure and hockey blades. Some people want an even smaller change - e.g., Mike Cunningham told me that one of the world class figure skaters he sharpens for wants the front outside edge on the jumping foot lowered by just .0005" - and apparently, she felt she could tell the difference, because they determined the amount by experiment. Of course that is slightly different - Mike sharpens the blade symmetrically, then dulls one edge a little bit more than usual, using a stone. That should create a less sharp lowered edge. (He always dulls edges a little, unless requested otherwise, to reduce the change a skater might otherwise notice between sharpened and unsharpened edges, and because extremely sharp edges are quite fragile. That said, I personally like sharp edges.)
Title: Re: CW crossovers and foot sliding
Post by: Leif on December 10, 2017, 03:58:26 AM
Unfortunately it's not possible to get better than 1/1000" around here except on rare occasions. Yes I too like sharp blades.

I had them redone, and my right foot no longer slides when doing forward CW crossovers. I still need to work on technique though as they are nowhere as good as my ACW crossovers. The sharpener did suggest a deeper hollow. I am just over 11 stone, or 70Kg, and the local rink has hard ice, so maybe 1/2" is more appropriate.

I will for sure buy a machine, either a ProSharp or a Sparx. The latest sharpen was on a ProSharp machine, and it feels very good.
Title: Re: CW crossovers and foot sliding
Post by: Query on December 10, 2017, 12:16:12 PM
Before getting too far into sharpening your own blades, maybe you should get a coach or at least a good skater to evaluate whether skating technique, rather than sharpening technique, might be the root cause?

I would stay away from the automatic sharpening machines for figure skating blades, for several reasons. But even for hockey blades, they probably don't give you as much freedom to experiment as hand-guided tools and machines give you. (Not surprising: freedom to experiment is also freedom to mess up.) If you decide to sharpen yourself, in addition to checking relative edge heights, I strongly suggest you trace or photocopy your blade NOW, so you can match the rocker profile to what it is now, rather than gradually and accidentally changing it with time, as I initially did. I don't know if those automated sharpening machines let you fix rocker profiles, but at least you would know when it is time to take the blades to an expert.

1/2" ROH is the most common NHL-plyayer-preferred ROH, according to one study, so it can't be TOO bad. But 7/16" is somewhat more common for figure skating, perhaps 3/8" for thin-line Dance blades, but bigger ROH are more common for school figures (to improve glide).

I suggested before that this may not be the best forum to get well informed hockey equipment discussions, because hockey isn't the forum's focus. Several hockey forums have discussed DIY sharpening at length.

I've met many hockey players who sharpen their own blades using hand tools - though that is most common for hockey goalies, because they have special needs that are not met by many hockey skate techs. Even more hockey players straighten their own knocked down edges, and perhaps do touch-up sharpening, but occasionally take their blades to a good skate tech, to get the rocker profile restored to what they need. So, if hockey is your interest, try asking around the good hockey players, hockey coaches, and especially goalies that you know, and it is possible you will find a few who do it, and could give you pointers.

Title: Re: CW crossovers and foot sliding
Post by: Leif on December 10, 2017, 03:28:20 PM
As I clearly said in my previous post, the sideways sliding is gone, what remains now is to improve my technique. However, as I've also said it's very hard to get a decent sharpening where I live. That means that the only real solution is to buy a machine. A traditional machine is out as I do not have a heated room to store one. They are big, heavy and messy. So an automated machine is the only option. I know they work well, and they are consistent.

As for your constant attempts to push me away from the forum, I've found posts from others very informative and helpful. Hockey skate wearers can learn a lot from figure skaters, even though there are difference.