How to check if a blade is warped

[Christy]

Please can someone remind me how to check if a blade is warped. I had my blades sharpened two weeks ago and the left one hasn't felt right since. It's not the sharpening. The blade feels like it's not straight, but it looks straight.

[Query]

Hold a reasonably good quality rigid straight edge up to it. There should be no gaps (places where light can shine through) between the straightedge and the blade.

Of course - how do you know the straight edge is straight? Well you could place two straight edges against each other, and see if there are any gaps. Also slide them against each other - still no gaps. Technically one could happen to be concave and one could happen to be convex in an exact match, but I think the test is pretty good.

Another question is how far off they can be. I think under 1/10 mm is fairly good, but don't know what other people would say. For me, I don't want to see any light between the two objects. One skate tech told me that about 1 mm (if I remember right) is the max he would even try to straighten, because if a blade with more would likely break when he straightened it. Anything with more than that, he returned to the blade maker. (But to do that, he was willing to pay return shipping costs - and the blade maker just sold them to another less picky tech, because he bought up some blades from another shop, and noticed one of the same blades. Needless to say, his shop didn't sell at a discount.)

Perhaps people with fancier tools could do something with a laser sight, or something like that.

Anyone else with other opinions?

[Bill_S]

I use a stainless steel ruler held against the side of the blade, slightly below the chrome relief, to check for blade straightness. A little warp is fairly common, but too much will affect skating.

This photo shows about the limit of warp that a skater should tolerate. I skated on this blade with no ill effect noticed.



Even a plastic ruler could get you the information that you need.

[Query]

BTW, the primary issues that warp can create are:

1. Sharpening. On a simple pro shop sharpening machine, if they don't have the fancy blade holder that forces the blade to de-warp while sharpening, you can create long edges on one side at the ends, and on the other side in the middle.

2. Drag. You may not glide as long or fast per stroke.

3. Heat. I had one blade pair that got hot when I skated. (It was Coronation Ace, and I thought that was just a very slow design, but I now think the warp played a part.) The same skate tech who fit my custom boots wrong also failed to notice that the blade was seriously warped. Heat isn't bad, but it is a sign that energy is being wasted. I don't think many blades are bad enough to get sensibly warm, but if you notice that - not good.

When you say it doesn't feel straight, do you mean that it doesn't glide along the right direction, or that it tends to turn when you don't want it to? That might have to do with how the blade is mounted with respect to your personal anatomy (Though a new sharpening wouldn't normally create that.), or in an extreme case, it might be caused by unequal or uneven relative edge (inside vs outside) lengths.

Try this: stand up the skate and blade, so that it rests on both edges. Does the blade still stand up vertically? If you happen to have a T-square, or even a book, you should be able to figure out whether the blade is at right angles to the surface. Try it along several places along the blade.

A better test is to invert the boot and lay that straight edge across the blade. It should be at right angles to the blade, not tilted one way or the other. If you have several straight edges, you should also be able to sight along both of them, and see that they are oriented the same. I'm not sure if that explanation was clear enough... There are purpose-made tools for this, and great techs often buy them. Maybe your pro shop has them, and could try to prove to you that they did everything right.

[Christy]

Well I finally got a steel ruler and checked the blades. The left one is warped around the toe pick and rocker, so now I need to fix the problem. I know it happened when the skates were sharpened. Is there any way I can fix the problem myself?

[tstop4me]

Well I finally got a steel ruler and checked the blades. The left one is warped around the toe pick and rocker, so now I need to fix the problem. I know it happened when the skates were sharpened. Is there any way I can fix the problem myself?

Assuming you are comfortable demounting the blade, I would first demount the blade and check whether the blade is still warped in the demounted state.

[ETA:  By the way, are these the Matrix Elite you discussed in another thread, or some other blade?]

[Christy]

They are the Matrix Elites. This is the third pair I've had over about 6 years, and the first time I've had a problem with warping. Is there a way of fixing the problem without demounting? I will do that if I have to, but I'm not totally confident.

[tstop4me]

They are the Matrix Elites. This is the third pair I've had over about 6 years, and the first time I've had a problem with warping. Is there a way of fixing the problem without demounting? I will do that if I have to, but I'm not totally confident.

The issue is trying to determine what happened.  You suspect that the sharpener warped the blade.  Assuming he did, there are two ways I can see that happening:

(1) The blade was loose, and he readjusted the mounting incorrectly.  The blade is warped under tension, but not permanently.  That is, if you demount the blade, it will spring back to a straight blade.  Nothing is needed to be done to the blade.  You just need to remount it properly.  This is the best case scenario.

(2) The blade was clamped improperly in the skate holder, and a lot of pressure was applied.  The Matrix Elites have an aluminum alloy chassis with a stainless steel runner.  The blade holder clamps onto the chassis.  So the chassis would have to be warped by the clamp, and the runner would have to be warped by the chassis.  I'm not sure a typical skate holder can exert enough pressure to do such damage; which is why I think you should check for (1) first.  Of course, there is the possibility of some bizarre accident:  e.g., the skate is clamped in the holder, and the whole assembly gets knocked onto the floor.

[Christy]

I don't think it's the first option as I actually checked the blades just before I took them in to be sharpened and they definitely weren't loose.

I'm actually wondering if it's possible the sharpener dropped them?

[tstop4me]

I don't think it's the first option as I actually checked the blades just before I took them in to be sharpened and they definitely weren't loose.

I'm actually wondering if it's possible the sharpener dropped them?

I'm assuming you don't trust the sharpener to remedy the situation.  Is that correct?

As for trying to see if you can fix it yourself (if possible), I would strongly advise demounting the blade first.  Even if the blade doesn't spring back straight, you would still want to demount it before trying to straighten it (not guaranteed it can be, depending on what happened to it).

[Query]

Ouch! The idea that it happened during sharpening is very strange. I wouldn't have thought that dropping the skate alone on the floor would be enough.

In most of the sharpening machines I have seen, the clamp that holds the boot and/or blades is part of the machine, and you would have to knock the entire machine over to do this to the blade. in most pro shops the sharpening machine is extremely heavy. Baring an earthquake, I find that hard to imagine happening by accident.

However, tstop4me is absolutely right - if the screws were tightened badly (e.g., if one hole stripped, and the tech added a new hole, in slightly the wrong place), it could be the bad mount is creating the warp. If removing the boot straightens the blade, all you may need to do is to remount it properly.

However, maybe the sharpener tripped and accidentally leaned his or her own weight on the boot, knocking it into the wheel? That idea sounds pretty strange. A really honest tech would have admitted his or her error, and reimbursed you for the cost of the blade.

Were I you, I would not be overly impressed by the skate tech you used. It is my personal belief that it is a good idea to recheck the blade for warp after mounting, though that's partly because my mechanical skills are not that great, and I need to allow for error.

Remember, it is possible to break a blade when you de-warp it. You can break the pieces of metal, or the braise or weld where the runner is attached to the rest of the blade. It's one of the reason many experienced techs prefer to return blades that are significantly warped when they are new, rather than dewarp them. That said, they have a device on many sharpening machines specifically designed to unwarp them, though it looks to me like it is designed to do the job very fast - presumably making breakage more likely.

Do you own a vice, or can you borrow the use of one? If you placed the warp section inside the vice, and tightened it, with something a little bit thick placed against the blade in an appropriate place it would reverse the bend. To avoid breakage, it might make sense to do this slowly, bending it only a little back at a time, until you get it straight. Also, you want something smooth in between the blade and the parts of the vice that touch it, like lots of layers of paper or cloth, so the grooves in the vice doesn't impress their form on the blade. Oh yes, first use a straightedge to check that the parts of the vice that clamp down on the blade are themselves straight. You don't want the vice to add more problems!

I haven't actually done this operation myself, so no guarantees. Perhaps tstop4me or someone else can think of a better method, or a better tool?

Anyway like tstop4me, I would demount the blade first, because the weight of the boot might otherwise warp the blade along another axis. That said, you always need to be careful when remounting, because it is so easy to strip the screw threads in the hole. Also, if the vice tightens horizontally (most do), then the boot stays vertical, and need not warp, so de-mounting might not be needed - though I suppose the weight might not be completely symmetric, so I personally would de-mount it anyway.

I think an ordinary wood clamp (such as those used to hold together pieces of wood that are being glued together) would work as well. In fact, most of the ones I have seen do not have grooves, so might be better. Given a choice, I think I would prefer a nice smooth-jawed clamp to a grooved vice - though I believe some vices are smooth-jawed too. But most clamps won't hold the blade and therefore the boot vertical, so de-mounting would be more important.

Whatever you do, please tell us how it goes, so we can add another data point.

BTW, how much (by how many mm) is the blade warped? And exactly what did you feel on the ice that told you something was wrong?

[tstop4me]

In most of the sharpening machines I have seen, the clamp that holds the boot and/or blades is part of the machine, and you would have to knock the entire machine over to do this to the blade. in most pro shops the sharpening machine is extremely heavy. Baring an earthquake, I find that hard to imagine happening by accident.

Common sharpening units used in pro shops these days are made by Blackstone or Blademaster.  These use a separate skate holder that glides along a horizontal flatbed table; you can lift up the skate holder and chuck it out the window if you wish.  :-)  It is not affixed to the body of the sharpening machine.  The same configuration is used by the Wissota machine that Bill has.

But you're right, there are some machines in which the skate holder is integrated into the sharpener,

[Query]

Common sharpening units used in pro shops these days... use a separate skate holder that glides along a horizontal flatbed table; you can lift up the skate holder and chuck it out the window if you wish.

OK. Does the skate tech up the skate holder to attach the skate or blades? And is there any reason it wouldn't stay immediately next to the sharpening machine, and how its center of gravity wouldn't be over the table with a large margin? I'm trying to picture how it ends up on the floor. It has to be heavy enough not to fall over from the weight of the skate, right? So, I'm having trouble imagining it being often picked up off the table.

Unless - I guess you might pick it up in order to clean filings off the table? So, if you mounted the skates in the holder, THEN realized it was time to clean off the table, it could happen. Is that what you imagine happening?

Or have I got that all wrong.


I forgot to ask the o.p.: Does the blade base have countersunk holes (i.e., the top of the holes are conically shaped) and are you using countersink head screws that fit snugly into them? That helps control the way the screw centers on the holes, so you can't tighten them in a way that pushes the blade away from the original mounted positions. It leads to more consistent mounting.

Also, are the tops of the screws level - meaning that they are parallel to the base? This too helps control the centering. If that wasn't done right, the exact shape imposed on the blade might change if you re-tighten the screws off-axis. Every time I re-tighten, I find I have to be careful that the screw stays vertical.

I know these questions are pretty basic, and please, I mean no offense to your mechanical skills by asking. But if you don't realize that these things are desirable, re-tightening the screws wrong might actually create a warp.

In fact, a small ordinary blade warp (in which the warp occurs about a vertical axis) can be compensated for simply by changing the mounting screw positions. (Perhaps by using different screw holes; otherwise you have to fill the old holes with something like wood strong enough to be drilled with the proper positions.) You wouldn't want to change it a lot that way - you might accidentally create a "twist-warp" (a twist around the horizontal axis, that is around the long axis of the blade), which you have to work a little harder at to correct.

BTW, you can actually warp blades by having an on-ice collision between skate blades. E.g., if an evil hockey player, or a beginning level skater, skated into your precious figure blades. (Apparently, this happens rather often among hockey players.)

[tstop4me]

OK. Does the skate tech up the skate holder to attach the skate or blades? And is there any reason it wouldn't stay immediately next to the sharpening machine, and how its center of gravity wouldn't be over the table with a large margin? I'm trying to picture how it ends up on the floor. It has to be heavy enough not to fall over from the weight of the skate, right? So, I'm having trouble imagining it being often picked up off the table.

Unless - I guess you might pick it up in order to clean filings off the table? So, if you mounted the skates in the holder, THEN realized it was time to clean off the table, it could happen. Is that what you imagine happening?

Or have I got that all wrong.

I’m not imagining anything happening.  Before we go too wild, let me recap to place this discussion back in context.  I wrote:

The issue is trying to determine what happened.  You suspect that the sharpener warped the blade.  Assuming he did, there are two ways I can see that happening:

(1) The blade was loose, and he readjusted the mounting incorrectly.  The blade is warped under tension, but not permanently.  That is, if you demount the blade, it will spring back to a straight blade.  Nothing is needed to be done to the blade.  You just need to remount it properly.  This is the best case scenario.

(2) The blade was clamped improperly in the skate holder, and a lot of pressure was applied.  The Matrix Elites have an aluminum alloy chassis with a stainless steel runner.  The blade holder clamps onto the chassis.  So the chassis would have to be warped by the clamp, and the runner would have to be warped by the chassis.  I'm not sure a typical skate holder can exert enough pressure to do such damage; which is why I think you should check for (1) first.  Of course, there is the possibility of some bizarre accident:  e.g., the skate is clamped in the holder, and the whole assembly gets knocked onto the floor.

<<Emphasis added.>> So I never claimed that dropping the holder was the most likely scenario.  But that it was possible.  In the absence of further info, we can’t dismiss it.

To which you responded that it’s not possible for a holder to strike the floor unless the entire sharpening machine crashes to the floor:

In most of the sharpening machines I have seen, the clamp that holds the boot and/or blades is part of the machine, and you would have to knock the entire machine over to do this to the blade. in most pro shops the sharpening machine is extremely heavy. Baring an earthquake, I find that hard to imagine happening by accident.

And I then pointed out that what you wrote simply does not apply to many sharpening machines in common use:

Common sharpening units used in pro shops these days are made by Blackstone or Blademaster.  These use a separate skate holder that glides along a horizontal flatbed table; you can lift up the skate holder and chuck it out the window if you wish.  :-)  It is not affixed to the body of the sharpening machine.  The same configuration is used by the Wissota machine that Bill has.

But you're right, there are some machines in which the skate holder is integrated into the sharpener,

Now with all that out of the way:

* With the machines I've discussed, the blade is oriented horizontally when the holder is resting on the table.  When techs I’ve watched want to inspect the edges, they don’t crouch down and view the edges from the side of the table.  They pick up the holder and flip it so they can look at the edges from various angles.  Similarly, when they use a square or edge checker to check for level edges, they pick up the holder and flip it.

* I’ve seen a busy shop with two stations and two techs working almost side-by-side in cramped quarters.  It’s not difficult for one guy to bump a unit left unattended by the other guy and knock it off the table.  And, hey, even a single tech can have an off moment and knock it off the table, or drop it, by accident.  I've knocked tools off my workbench; I've also dropped some.

* Techs I’ve watched typically have two (or more) holders.   They routinely pick up holders. 

So, for sharpening machines in which the holder is not integrated into the machine, the notion that a holder is quasi-permanently affixed to the body of the sharpening machine and the notion that a tech does not routinely pick up a holder (with or without a skate attached) are not correct.

[tstop4me]

They are the Matrix Elites. This is the third pair I've had over about 6 years, and the first time I've had a problem with warping. Is there a way of fixing the problem without demounting? I will do that if I have to, but I'm not totally confident.

If you're not confident about demounting (and remounting) a blade, then I would advise you not to try straightening it yourself.

[Query]

I wasn't disagreeing, just trying to understand. It didn't happen to seem likely on the machines I've seen or the machine I tried to use.

I'm willing to accept that those things are possible. Maybe even more so on the 3 station machines. After all, it presumably would add significantly to the size, weight and cost of the machine to have lots of space between the stations. They are already pretty big and heavy, and remarkably expensive. Add the pressure I've noticed in some shops that managers place to sharpen as many blades as possible per hour, and a few errors might be inevitable.

I confess I've even managed to know computer mice and trackballs off a desk or table. It happens because my eyes are on the screen, and I mostly don't look at my hands or the mouse or trackball.

But we seem to be scaring the o.p. away from the idea of dealing with the problem herself.

I was initially scared of dealing with boots and blades myself too, an attitude that skate techs often encourage, and I did make some mistakes, but in the long run I was a lot more happy with my own results than with the rather inconsistent results I got from commercial pro shops, even from the best ones I could find. To some extent its also hard to figure what a commercial skate tech might have done wrong if you don't try to do things yourself. Plus, I sometimes find it fun to figure out what works and what doesn't, much like skating itself. Trial and error are often part of such a process.

E.g., while it is true you can easily strip the hole threads in a leather outsole, e.g., by overtightening, and while an incorrectly used, sized or type screwdriver can even strip the tops of the heads that the screwdriver fits into, which scares some people away from messing with screws, those are both fixable problems. I'm not sure we should discourage her. Especially if she lacks confidence in the skills of the available skate techs.

[Christy]

The boots are Edea so it's the standard Edea screws. I check that the blades aren't loose after most sessions and so far haven't had to tighten them since they were fitted.

The sharpener doesn't sharpen in view of the customers. He takes the skates away then returns them about 10 minutes later. I just wondered if the skate may have fallen on to the floor accidentally, and that's caused the warping.

[tstop4me]

The boots are Edea so it's the standard Edea screws. I check that the blades aren't loose after most sessions and so far haven't had to tighten them since they were fitted.

The sharpener doesn't sharpen in view of the customers. He takes the skates away then returns them about 10 minutes later. I just wondered if the skate may have fallen on to the floor accidentally, and that's caused the warping.

Having the skate fall on the floor accidentally is one possible cause (out of several).  But in the absence of any further info, we'll never know.  Perhaps we should rewind.

(1)  In your previous post, you were considering swapping your Matrix Elite for an MK Phantom because your tech couldn't handle the Matrix Elite, or you didn't trust him to.  But now in this thread, you said the Matrix Elite has been sharpened.  Is this by a different guy?

(2)  You led off this thread by stating that you are having an unspecified problem, you are certain that it is not due to sharpening, and you suspect that the blade might have been warped by the tech.

(a) What problem are you having?

(b) How can you be certain that the sharpening is OK and not causing your problem?  Checking the evenness of the edges on the Matrix Elite is difficult.  A machinist's square doesn't work.  An HDI gauge doesn't work.  Most two-piece edge checkers (the one with a reference horizon) don't work [Paramount makes a custom one that does work].  So your only ready recourse (i.e., one that doesn't require a special setup) is a one-piece edge checker where you eyeball the levelness against an imaginary reference horizon.  Have you checked your edges with one of those?

(c) Since you are only now asking about how to check for a warped blade, I assume you didn't check for warp before you brought the skates in for the recent round of sharpening.  Is that correct?  If so, then you can't say for certain that the blade was straight when you handed it to the tech and that the blade was warped after the tech handed it back to you and that therefore the tech caused the warp. 

[Christy]

It's a bit confusing but I'll try to explain. I'm stuck in Canada unable to cross the border to my great skate tech in the US, so I'm having to use local sharpeners. The first sharpener I tried does not have the correct equipment to sharpen Matrix blades so has created a workaround. He checked the blades when I got them and said they weren't warped. He had 4 attempts at sharpening, none good, and each had different results, probably because he's not using the correct equipment.
So I tried a different sharpener who works in a chain sports store but does other figure skaters boots and does have the equipment for matrix blades. The first time he sharpened my blades they were OK. Not as good as my great US skate tech, but usable. The sharpening didn't last very long - 20 hours, so I had them sharpened again and from the first time I stepped on the ice after that sharpening my left skate / foot / blade has felt like it's being twisted.
I tried removing the boot, retying the laces, etc. but that didn't make any difference, so I asked about checking for warping. When I checked against a steel ruler the blade is off / warped with a bend in the vicinity of the rocker / toe pick. The blades feel like they have uniform sharpness when I run my hand down them.

[tstop4me]

The sharpening didn't last very long - 20 hours, so I had them sharpened again and from the first time I stepped on the ice after that sharpening my left skate / foot / blade has felt like it's being twisted.
I tried removing the boot, retying the laces, etc. but that didn't make any difference, so I asked about checking for warping. When I checked against a steel ruler the blade is off / warped with a bend in the vicinity of the rocker / toe pick. The blades feel like they have uniform sharpness when I run my hand down them.

<<Emphasis added>>.  Yeah, but that doesn't tell you whether the edges are level.  I have a hollow depth indicator (HDI) gauge that measures depth of hollow and also difference in height between the inside and outside edges (.001 inch graduations).  I check a blade at 1 inch increments along the length of the blade, starting at about 1 inch from the drag pick.  I take measurements before and after a sharpening.  What I've found is that, even with a good tech, there are times when the edge levels are off.  And more, importantly, the degree of unevenness is often not uniform along the blade, with the worse problems being toward the front of the blade near the critical spin rocker.

So I think there's at least a possibility that your blade was warped going in, and the sharpening is messed up.  As I mentioned before, you're not in a position to go back to the tech and say, "Hey, you warped my blade!", since you can't substantiate it.  Perhaps it's best to go back, describe the problems you're having, ask him to check the blade, and see what he says.  Then take it from there.  At the very least, I would still have the tech demount the blade and check for warp.

[Query]

after that sharpening my left skate / foot / blade has felt like it's being twisted.

Twisted about which axis?

If when you tightened the screws, the blade ended up mounted in a slightly different location, because you could get a twisting force (torque), about either a horizontal or vertical axis. That's why I was asking about the countersunk holes and screws, and whether the screw heads were all flat to the surface - for the most part they lock you into a specific location - unless the holes weren't drilled in consistent locations, so that there is no way to fully engage all the countersinks.

But if you are unwilling to demount the blades, it might be hard to check for countersinks. You can look at screw head level.

I've personally never had a blade so warped that the warp itself created a detectable twisting force, (except on speed skates, which are deliberately warped, because they always go counterclockwise). But in principle that is possible, if they were really, really bad.

Also, if you suspect the skate tech is at fault, maybe you don't want to make major long-term equipment changes, like playing with mounting positions, if you aren't confident about doing the work yourself.

If the twisting force is about a horizontal axis, e.g., if it wants your ankle to twist left or right up forward or back, there are things you can do to play with a temporary insole to compensate - and you could restore the old insole when you can get back to the U.S.

You don't actually need expensive equipment to do a somewhat inexact check for edge levelness. To a first approximation, you can lay a straightedge (e.g., ruler) across the blades, and see if it looks like it is at right angles. Also, If you lay two straightedges across different parts of the blade, you should be able to sight along them and see whether they line up.

Plus, the skate tech who has the equipment to handle matrix blades probably also has level indicators that he/she could use to check yours.

If you ask around, I'm willing to bet Canada has some really great skate techs, because they have a lot of skaters, and some of the world's best known skaters and coaches. Is traveling to a great tech a possibility, or has Canada locked down intra-national travel too?

It is so unfortunate that you found a skate tech you trusted, and can't travel to that person. A lot of skaters never find someone like that.

P.S. 20 hour edge life isn't all that bad, depending on the surface quality, cleanness and temperature of the ice. When I skated outdoors, I sometimes didn't do that well. Have you at least managed to find an indoor rink with nice ice?

[Christy]

I'm confused by the vertical / horizontal axis, however my foot feels like it's being lifted slightly and twisted to the side at the front, and the blade is bent at an angle around the area of the rocker.

[Query]

OK.

What might be happening is that the warp is causing one edge to be longer and sharper than the other (which will not be very sharp) in one part of the blade (e.g., in the center), and the other edge to be longer in another part (e.g., the ends). Somewhere in between, they will be the same length and sharpness. Or maybe they will the same length at the ends (because that is where the skate tech usually adjusts the machine), but longer and sharper on one side in the middle. Gravity will try to push you to tilt (or twist) towards where the edge is short. And since the blade is less sharp there, you will tend to skid on that part of that edge.

Let me explain why a warp could cause these  problems:

The sharpening wheel first is "dressed" (ground) to have a circular cross section somewhat like a coin. Think of it as an abrasive penny that sits sideways across the bottom (hollow) of the blade. In fact, it will be used to create that hollow, and therefore the two edges along the sides of the blade.

(That's not quite right, because the wheel rotates along the blade - but let's ignore that rotation for this simple description. Also, in most sharpening machines, the bottom of the blade is actually mounted to stick out sideways, so the wheel rotates in a horizontal plane - but ignore that too.)

Now if the penny is exactly centered on the thickness of the blade it will grind a symmetric shape, namely the hollow, and the two edges, formed by the intersection of the hollow curve with the sides of the skate, will be the same shape, except they will be mirror images of each other.

But if you push that penny over to one side, so it is no longer centered across the thickness of the blade, the edge on that side will be shorter, and be somewhat rounded off. So centering is critical.

Pro shop sharpening machines let you adjust the centering of the wheel (in our simplified model, the abrasive penny) across the thickness - sometimes at one point along the blade, but the better ones let you adjust that centering at two points - e.g., both ends of the blade.

The blade then travels in a straight line along the wheel, following the shape of the blade, at least if that blade is straight, not warped. That should do a perfect job.

But assume the blade is warped. That straight line of travel does not follow the warp of the blade. So, it will be centered differently on each part of the blade, and the two edges will be different lengths along different parts of the blade, and it will not be all that sharp on both edges on most of the blade. Even if your skate tech is very good.


(On some machines, the skate tech holds the boot in his/her hands and rests the blade on a table next to the wheel, and they could theoretically tilt the boot and blade a little to compensate - but that would require very steady hands and very high hand control and skill to do it right. So let's assume they can't do that.)


High end figure skate pro shops have an expensive blade holder that clamps down on the whole length of the figure skate, and forces it to be unwarped - at least while the blade is being sharpened. So the "penny" stays centered along the whole length of the blade, and both edges can be sharp and of the same length.

But the fancy blade holder/clamp doesn't fit hockey skates. Since most pro shops do most of their business with hockey players, it isn't worth it to them to buy that fancy tool. They may not even know about it.


Warped blades are a case where good hand tools like the Pro-Filer can do better. It has a 3" long abrasive cylinder instead of the abrasive coin that we imagined. Like the coin (or dressed wheel) it has a circular cross section that rests across the hollow of the blade. It is placed and held within a handle that has a slot the blade fits into, to force it to be centered across the thickness of the cylinder.  It is then slid along the hollow of the blade, grinding it to the proper shape. (That is slightly oversimplified, in part because the gap size may not be exactly right for your blade, but you get the idea.)

In theory that should have exactly the same centering problem as the sharpening wheel, because the cylinder is straight, and doesn't follow the warp of the blade. But 3" is shorter than length of the blade. So the warp creates less of a centering problem.

There was another older hand tool - the Berghman sharpener - that only had a 2" long cylinder. (They are less expensive on eBay, but the picture on Amazon is nice and clear.) Since it is 2" long, it would have even less of a centering problem - though the original cylinders were made of a type of abrasive stone that crumbled, and they also used a rather coarse abrasive that worked fast, but didn't create quite as sharp an edge. But if you replaced the cylinder with a more modern material, it would probably do better than the Pro-Filer. Plus, unlike the Pro-Filer, it also had an adjustable gap size, was essentially self-centering, and it let you see what you were doing better, especially when working near the toe pick, so it was a better design, IMO.

Both these tools have limitations. The kit with gap sizes wide enough for figure skates only comes in 3/8", 7/16" and 1/2" ROH (radius of hollow) versions - and the 7/16" kit, last I knew, was actually 3/8". And the Berghman tools only came with 1/2" ROH. Since 7/16" ROH is what most figure skaters choose, and some choose custom radii, neither tool is ideal for some figure skaters. In contrast, good pro shop sharpening machines let you dress the wheel to arbitrary radii. Plus, it takes time to learn to use any tool yourself, and you may have to learn by making mistakes. But it sounds like the skate techs you found in Canada are also learning from their mistakes, on your expensive equipment, and are trying to work around hardware that can't do the job - though perhaps the second one could if he/she unwarped (dewarped??) the blade. (I'm a little worried when you say that all the warp is right up front. If it is a major bend, that could mean that unwarping it would cause it to break.)

Did you ask around to see if you can find a really good figure skate tech in Canada that you can get to? That is still likely to be the least trouble-prone solution for you, and you don't need to worry about learning to use tools yourself, or figuring out what is going on.

[Query]

One other idea: Contact your preferred skate tech and talk to him/her. Mail your skates back to him/her and have him/her mail them back after solving the problems.

Yes, you have no skates for a few days. But you are wasting a lot of time, unhappiness, and money on this. Is there overnight mail or something equivalent from Canada that can go fairly fast?

Make sure the skates are well packaged, and the box is marked "fragile". I once sent a high end kitchen pan as a gift through the mail. It arrived totally twisted. Something weighing hundreds or even thousands of pounds must have been placed on top of it. I didn't think it needed to be marked fragile, but I was wrong. Perhaps the tech can give you advice.

[Christy]

Looks like it'll cost me around $120 to ship the skates with around 3 day shipping in each direction, and when they are returned to Canada I'll risk customs charges even though they are used. I'm going to talk to the good sharpener to see if he thinks he can help, and if he knows of good ways to ship the skates safely.

However I've been looking at the blade again and I think it's actually bent, not warped. The area around the stanchions isn't warped / bent, but the front of the bottom of the blade is bent. I'm not sure if this means that it can't be fixed?