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Author Topic: Sharpening J W Gold Seal blades  (Read 5801 times)

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Offline mnrjpf99

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Sharpening J W Gold Seal blades
« on: October 24, 2016, 05:57:13 PM »
I just bought a used pair of Edea Ice Fly's with J W Gold Seal blades. As many of you probably know, these blades are tapered. Even though they are sharp at the moment, I am wondering, when the time comes, if they have to be sharpened differently than a straight blade?

Offline Query

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Re: Sharpening J W Gold Seal blades
« Reply #1 on: October 26, 2016, 01:11:20 AM »
Bear in mind that I do not own Gold Seal blades, and have never bothered measuring them to check their shape. So if these guesses are wrong, what I say may also be wrong!

There are several issues here:

At http://www.worldsbestblades.com/products/gold-seal Wilson says that Gold Seals are available with two options:

  A. "Taper Side honed: Narrowed at the tail to reduce friction on the ice."

  B. "Parabolic" (Narrowed at the center): "Technology that centres your weight to increase stability and precision."

If A. applies to your particular blades, then there are two possible problems.

  (i) The side hone, according to http://www.tidewaterice.com/paramount_figure_skate_blades.htm , refers to a dovetail cut, which means the blade is also thicker at the bottom. That means that if the sharpener doesn't exactly preserve the rocker profile, the thickness of the blades may not preserve the taper - it may get thinner and wider in an irregular pattern, which may create problems you (the skater) has to compensate for - and compensate for differently every time you sharpen.

  (ii) Paramount (a competitor to Wilson), says at http://paramountskates.com that "Paramount offers precision tapered blades, thick in front and thin in back.  Although MK-Wilson also offers tapered blades, theirs are tapered by hand, with no consistency. Inconsistent tapering means the blade may be tapered more on one side than the other, and for the skate sharpener it would be impossible to get a even edge down the  length of the blade. The only way to do this would be to raise and lower the sharpening jig as the skate sharpener sharpens down the length of the blade. Paramount is offering a tool for the cost of $25.00  to check uneven blades, such as the Gold Seal, Phantom, and the Matrix Supreme."

Actually there is another problem, depending on how the blade is held in the sharpener. If the blade holder grabs the blade in the upper part of the blade, that has parallel sides, there is no problem. But if it grabs the blade in the lower part of the blade, where tapering and side honing apply, it would be very easy to impart a slant to the blade, that results in uneven (left and right) edges, in a way that varies with the position along the blade. This problem could also apply if your blade is Parabolic.

So, if at all possible, get the blade sharpened by a real expert. If you aren't certain the skate tech is that good, or you do it yourself, be very careful, first to preserve the taper - use a micrometer or very high precision calipers to check blade thickness near the bottom, before and after sharpening; and second to make sure that the edge heights (left and right) are even everywhere.

I also don't understand the front to back taper. Maybe that reduces drag a little, when skating forwards, but wouldn't it increase drag, when skating backwards? I think most freestyle skaters skate backwards more than forwards.

Anyway, I hope you love your new blades, and that your skate tech (or you) are up for it. You may want to pay your tech for a more careful sharpening, if he/she has that policy. You might also talk to your tech first, to see if he/she understands what is involved. I hope you like your new boots too.

Interestingly enough, different expert skate techs, as well as different skaters, differ on whether they believe that tapering, parabolic cut, and side honing make a significant difference to the skater.

Offline mnrjpf99

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Re: Sharpening J W Gold Seal blades
« Reply #2 on: October 28, 2016, 02:50:33 PM »
Thanks for the info. :0)

My Gold Seals, are a tapered bade and not parabolic.

In theory, from what I understand, the tapered blade is supposed to have a better bite, if I remember right.

You have a good point about drag and skating backwards. I would think it would cause more drag as well.

I haven't had a chance to try them yet, because I need to get my Edea Ice Fly's "reshaped" for my 240mm, (EE) feet, but that's another story... Lol

Offline Query

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Re: Sharpening J W Gold Seal blades
« Reply #3 on: October 28, 2016, 10:50:08 PM »
My Gold Seals, are a tapered bade and not parabolic.

In theory, from what I understand, the tapered blade is supposed to have a better bite, if I remember right.

I can't figure out any reason why a taper in of itself would create better bite. One thing it might do, in addition to reducing forward skating drag, would be to move the make it turn from front to back a little easier, and turn from back to front a little harder.

But are they also wider at the bottom (where the blade touches the ice), then a few mm above the bottom?

That's a "dovetail" cut, and probably would create a slightly better bite, because it creates a narrower edge angle. The equivalent of using a slightly smaller ROH, but the metal is taken away from the outside of the blade, instead of from the hollow region.

The difference might only be about .001" or so - you could measure it with a high precision calipers or micrometer - or maybe you could just slide a dividers up and down and feel the extra drag.

Offline mnrjpf99

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Re: Sharpening J W Gold Seal blades
« Reply #4 on: October 29, 2016, 10:29:38 AM »
On my blades, from the stanchion to the blade, is the same thickness, but from there down the blade it self tapers from front to back.

As you said, with the tapered blade, it kind of has a variable ROH from front to back. This is why I was concerned with the sharpening process. I am guessing, that the blade would take on the difference in ROH, because of the taper, when sharpened with a the proper wheel, such as for a 7/16 ROH. The critical thing would be the alignment of the blade when sharpened as you had said. I may be able to just hand sharpen it or something.

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Re: Sharpening J W Gold Seal blades
« Reply #5 on: October 29, 2016, 01:17:36 PM »
On my blades, from the stanchion to the blade, is the same thickness, but from there down the blade it self tapers from front to back.

As you said, with the tapered blade, it kind of has a variable ROH from front to back. This is why I was concerned with the sharpening process. I am guessing, that the blade would take on the difference in ROH, because of the taper, when sharpened with a the proper wheel, such as for a 7/16 ROH. The critical thing would be the alignment of the blade when sharpened as you had said. I may be able to just hand sharpen it or something.

That's not how it works.  Assuming (a) the blade is symmetrically tapered from front to back (toepick to heel) about a center longitudinal blade axis, (b) the sharpener aligns the blade and the wheel properly, and (c) the machine and sharpener are working properly [lots of assumptions], the ROH will nominally be constant along the whole length of the blade (there will be some variation due to uncontrolled factors such as chatter).  For a constant ROH, however, edge parameters such as depth of hollow, included angle, and bite angle will vary as a function of blade thickness.

Do you have a micrometer?  I'm curious as to how much the taper is; that is, what is the blade thickness near the toepick, and what is the blade thickness near the heel?

Offline mnrjpf99

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Re: Sharpening J W Gold Seal blades
« Reply #6 on: October 29, 2016, 01:52:08 PM »
I think I have a friend that has a micrometer. I will check and let you know. I am curious myself now. :0)

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Re: Sharpening J W Gold Seal blades
« Reply #7 on: October 29, 2016, 04:24:55 PM »
I think I have a friend that has a micrometer. I will check and let you know. I am curious myself now. :0)

Great.  It's a bit tricky, but get comparisons across the chrome relief, as well as further up on the chromed body.

Offline Query

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Re: Sharpening J W Gold Seal blades
« Reply #8 on: October 30, 2016, 05:32:38 AM »
On my blades, from the stanchion to the blade, is the same thickness, but from there down the blade it self tapers from front to back.

I guess I wasn't clear.

With regards to the "dovetail cut", I was talking about vertical thickness variation, not horizontal variation. Some expensive blades from MK and Wilson are side-honed in such a way that they are a little thicker (maybe .001 - .003 inches?) at the very bottom working surface, than a few mm higher. The variation is gradual, not steped, so the blade cross section is shaped like a wedge, wide part pointed downwards, though I doubt you could see that small a variation with your unaided eye.

Of course that means the blade gets thinner at the working surface as it wears out, and when it is sharpened. And it gets very irregular shapes (thickness variation, at different horizontal positions along the blade) if the sharpener doesn't preserve the original rocker profile - or if the manufacturer didn't grind everything exactly right to begin with. Which is why you need an expert with such a blade, someone who also cares and measures carefully. An expert can't eliminate the change in thickness with wear and sharpening, but he/she can make it uniform down the length of the blade, or preserve the intended taper or parabolic variation.

Dovetail cuts may also reduce the working lifetime of the blade, because once you get above the place where they milled in the dovetail cut, the side-honing will disappear. In addition, because I think MK and Wilson (which are now the same company) side-hone guided by hand (using a milling machine, I guess??), rather than by precision CNC, it is very easy for them to get it wrong, or even to grind the two sides asymmetrically. Some expert skate techs say they have seen all these problems on factory-fresh blades from MK and Wilson.

No wonder most other brands leave the sides of blades parallel! - although Dance blades are often milled thinner ("thin-line") at the bottom, but that variation is stepped, not gradual.

Mike Cunningham, a world-class skate tech, said he thinks that all forms of horizontal and vertical thickness variation (except the thin-line dance blade, of course) don't make a significant difference to the skater, and aren't worth the extra hassle to the skate tech (and which many less  expert skate techs botch!!) - though he will supply whatever the skater wants if asked. John Harmata ("Mr. Edge."), another world-class skate tech, says that thickness variation sometimes does help. Many individual figure skaters have differing opinions too.

Is thickness variation worth it, and does it help?

I have not tried any blades with thickness horizontal or vertical thickness variation, except for thin-line dance blades. I'm perhaps not a good enough skater to notice the difference, if there is one. And, since I sharpen my own, I don't want the hassle of checking thicknesses at many points along the blade with a high precision micrometer or calipers, or checking left-to-right symmetricity (with a straight edge and a magnifying glass, I guess).

But you already have the blades you have. So parallel sides aren't an option.

BTW, horizontal side-honing - in particular parabolic shapes - have become extremely common in skis and snow boards, and is supposed to improve turning. But that isn't by a few thousandth's of an inch, it is by a large fraction of the ski wdith - see for example

  http://www.skiwithbob.com/parabolicskis

So you can happily show off your "new-to-you" blades to your friends, using a micrometer, and talk about how it is SO important, and make them green with envy. It doesn't matter whether it actually helps, or whether inexpert skate techs will botch them, only that it makes you feel better about yourself. :)

Offline mnrjpf99

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Re: Sharpening J W Gold Seal blades
« Reply #9 on: October 30, 2016, 08:44:36 AM »
I see what you mean about the dove tail thing. I noticed it last night, when I was looking at the blades. You are right; they are ever so slightly tapered vertically.

As far as having these blades go, I only have them because they are what came with the boots. To be honest, I kind of cringed when I found out they were a tapered blade. I would have rather them be a straight blade, like Pattern 99 or something for sure. I got the boots with blades on Ebay for $130. The boots are Edea Ice Fly's. I chose these because the price was right and they are able to be heat shaped. I have stupid wide short and wide feet.

If the boots pan out, I may end up trying to get a different blade anyway. Technically, the blades are too short for the boot. They are a 8 3/4" and my boots call for a 9" blade.

P.S. I could always just coat the Gold Seal edges with grease to keep them from wearing. Just kidding of course. Lol

Offline Query

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Re: Sharpening J W Gold Seal blades
« Reply #10 on: October 30, 2016, 07:41:58 PM »
Technically, the blades are too short for the boot. They are a 8 3/4" and my boots call for a 9" blade.

It is mostly the feet, not outsole length, that should determine blade length. That's because outsole length has no effect on skating. If the blades don't feel too short, they probably aren't. I.E., if there is a mounting position (forget that nonsense about their having to be flush with the front of the outsole) that makes you feel that reaching the toe pick feels right, which places the sweet spot (whose position can be modified, BTW) on top of or just ahead of the ball of your foot, and the back corner doesn't scrape and drag at the back, they aren't too short.

Quote
I could always just coat the Gold Seal edges with grease to keep them from wearing. Just kidding of course.

Edges touch the ice. Grease would come off when you skate, so wouldn't help. But grease, or oil, will reduce rust (you should completely dry the blades too), which CAN help significantly, because these blades are high carbon steel, not stainless steel.

I didn't mean to imply the blades are no good. A LOT of freestyle skaters LOVE these blades. They must do something right. (I'm not good enough to know exactly what, and I don't do freestyle.) If you don't have any problems with them, there is probably no reason to get rid of them, even if your skate tech isn't one of the best. They are very pretty too. These are top end blades. If they work for you, just ignore my silly objections.

If you don't like them, maybe you can sell them.

If heat molding makes the boots fit, and they aren't broken down, $130 was a great deal! With or without the blades.

Offline mnrjpf99

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Re: Sharpening J W Gold Seal blades
« Reply #11 on: October 30, 2016, 11:45:36 PM »
It's very true about where the blade is placed under the foot. For a short time, I had a pair of Riedell's, that were a size too big. The blades on them were not very good at all, so I simply mounted a better set of blades that were 1/4" shorter on the boots, about 1/4" (approximately one size) back from the toe, placing the toe pick at or just ahead of the toe. They worked out pretty good.

As far as the grease goes, I was completely joking. Lol

I like the Gold Seal blades for sure and as you said, they are a top of the line blade. It's just a matter of being careful when getting them sharpened.

I am very anxious to try them out. :0)

I was wondering something though. When you said you sharpen your own blades, did you mean with a sharpening machine or did you mean a hand held sharpener? If so, what kind?

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Re: Sharpening J W Gold Seal blades
« Reply #12 on: October 31, 2016, 04:54:59 PM »
[quote
I was wondering something though. When you said you sharpen your own blades, did you mean with a sharpening machine or did you mean a hand held sharpener? If so, what kind?
[/quote]

Hand-held. These kinds:
1. Pro-Filer.
2. Berghman skate sharpener (no longer made, but available used online.)
3. Home-made tools created by gluing sand paper onto dowel rods, using a strap to the rod on the blade.
4. Have also rejected the Skatemate sharpener, because the one I bought was very poorly made.

I briefly discuss sharpening at my boot modification page

  http://mgrunes.com/boots/BootBlade.html

BTW, there is a significant learning curve to sharpening your own skates. You can mess them up.

Offline riley876

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Re: Sharpening J W Gold Seal blades
« Reply #13 on: October 31, 2016, 07:24:42 PM »
BTW, there is a significant learning curve to sharpening your own skates. You can mess them up.

Absolutely.   Luckily low-quality well-flogged blades can be bought for spare change.  Probably OK to play with hand sharpeners on good blades, if you are careful,  but definitely don't touch your good blades with power tools until your technique is down pat.

Offline mnrjpf99

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Re: Sharpening J W Gold Seal blades
« Reply #14 on: October 31, 2016, 09:01:48 PM »
I checked out your link. A very good resource.

I have an old fashion hand sharpener, that I have used on cheaper blades, but would not dare use on a good blade. I like the tips about home made tools as well.

Thanks again for the valuable info. :0)

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Re: Sharpening J W Gold Seal blades
« Reply #15 on: November 01, 2016, 03:59:55 PM »
I checked out your link. A very good resource.

I have an old fashion hand sharpener, that I have used on cheaper blades, but would not dare use on a good blade. I like the tips about home made tools as well.

Thanks again for the valuable info. :0)

I have personal experience only with the Pro-Filer.  If you consider this option, try to borrow one first to make sure it will work.  This unit has a cylindrical sharpening stone housed in a chassis with a rectangular channel.  The channel slips over the sides of the blade and aligns the cylindrical axis of the stone with the longitudinal axis of the blade.  During sharpening, you slide the channel along the length of the blade.  The clearance between the walls of the channel and the sides of the blade are controlled by applying one or more layers of adhesive tape on each side of the blade.  Proper alignment is assured only if the sides of the blade are parallel. If the sides deviate too much from parallel, you might not get good results.  So check carefully how much taper you have on your blades (chrome relief region and chrome body region) and check the region of the blade along which the channel slides.

The instruction manual says the unit will work with a parabolic blade by placing extra tape along the center of the blade; that is, you pad the blade with tape to make quasi-parallel sides.  Not sure how well it works in practice.  With one pair of blades, I had to leave portions untaped because of blade thickness variations.  It's very easy to snag the edges of the tape during sharpening.  So one long continuous strip from pick to heel is preferable.

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Re: Sharpening J W Gold Seal blades
« Reply #16 on: November 01, 2016, 04:29:05 PM »
I attempted to sharpen a friend's parabolics (Phantoms, I think) once with my Pro-Filer kit, and found it much more trouble than it's worth.

I've since stuck to sharpening ordinary parallel blades with my Pro-Filer. It works like a charm on them.


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Re: Sharpening J W Gold Seal blades
« Reply #17 on: November 01, 2016, 06:07:30 PM »
The alternative would be to place tape on the outside portions of the sides of the channel - if the channel is wide enough.

Even with parallel blades, I prefer taping the channel to taping the blade. That way I can leave the tape in place.

If you can live with a 1/2" ROH, the Berghman sharpener might be able to do a good job on a non-parallel blade. Use a thick squishy foam or tape, and it should deform to match the blade. But maybe you don't need to, because the Berghman channel is far enough from the cylindrical stone that it may be sliding along the part of the runner that is parallel.

You could almost certainly do it with home-made tools, since with the strap, all that is important is that the two sides are symmetric - but it is a lot harder to center it on the blade that way than with either the Pro-filer or Berghman sharpeners - i.e., you need a lot of practice on old or scrap blades.

Regardless, with any of the tools above, it is a good idea to alternate a few strokes one way, then flip the sharpener around 180 degrees, and do a few strokes that way, to make the blade symmetric even if the sharpener isn't.

That said, I've never sharpened non-parallel blades, so this is all speculative.

An interesting question would be - does the difficulty sharpening non-parallel blades optimally really matter? I.E., suppose that you indeed get a wavy pattern to the blades, in which it is thinner in some places than others - will that substantially affect skating? Without trying it, it is hard to tell - and I might not be a good enough skater to tell even if it might matter to someone better. E.g., my spins are already sometimes poorly balanced, and sometimes poorly centered, so if the main effect were to mess up spins, I wouldn't notice.

The reason I ask this is that I wouldn't be surprised if 99.9% of skate techs don't understand non-parallel-sided blades at all, and do them completely wrong. Yet a lot of figure skaters are happy with non-parallel-sided blades. That suggests all of this might be largely unimportant, that really good skaters can compensate a lot for imperfect sharpening. I.E., it is possible that if you have good control and strength, minor blade imperfections become unimportant - that it is really those of us on the borderline who such imperfects affect most.

In fact, a lot of good skaters make do with blades that are sharpened by someone really incompetent, with uneven height (left-right) edges, whose relative height also varies along the blade, which seems like a more serious defect.

I have thought about deliberately introducing parabolic curves to the sides of my blades, not to the whole blades, but just to the edges at the very bottom, to see if that makes spins better. Since the sharpeners I use track on the main part of the blade, not the edge, that wouldn't affect sharpening in an adverse manner.


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Re: Sharpening J W Gold Seal blades
« Reply #18 on: November 02, 2016, 01:04:59 PM »
The alternative would be to place tape on the outside portions of the sides of the channel - if the channel is wide enough.

Even with parallel blades, I prefer taping the channel to taping the blade. That way I can leave the tape in place.

Not sure how taping the sides of the channel would compensate for non-parallel blades along the whole length of the blade.

For parallel blades, I can see how taping the sides of the channel is a lot easier than taping the sides of the blade, especially if you need multiple layers of tape on each side; and saves a lot of tape as well.   The advantage of taping the sides of the blade though is that the surface finish is protected should grit come in between the channel and the blade.

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Re: Sharpening J W Gold Seal blades
« Reply #19 on: November 02, 2016, 01:56:48 PM »
Not sure how taping the sides of the channel would compensate for non-parallel blades along the whole length of the blade.

I assume you use a slightly compressible tape, like foam tape, that adjusts to the width of the blades. That requires a channel width (some call it a gap width) that is somewhat wider than the blade - either originally, or because you file it. (I had to file mine to be a little wider because I use Ultima Matrix I blades, which are a little wider than the Pro-Filer manufacturer, Edge Specialties, assumes - though someone said Edge Specialties lets you custom order channel widths.)

Regardless, it is extra work - for you, or for your skate tech.

tstop4me, or anyone: Do you believe non-parallel blades have a perceptable benefit? If so, how did you come to that conclusion, and what type of non-parallelism was it for? (BTW, MK and Wilson offer many of their blades in parallel versions, if you ask them.)

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Re: Sharpening J W Gold Seal blades
« Reply #20 on: November 02, 2016, 04:11:33 PM »
I assume you use a slightly compressible tape, like foam tape, that adjusts to the width of the blades. That requires a channel width (some call it a gap width) that is somewhat wider than the blade - either originally, or because you file it. (I had to file mine to be a little wider because I use Ultima Matrix I blades, which are a little wider than the Pro-Filer manufacturer, Edge Specialties, assumes - though someone said Edge Specialties lets you custom order channel widths.)

Regardless, it is extra work - for you, or for your skate tech.

tstop4me, or anyone: Do you believe non-parallel blades have a perceptable benefit? If so, how did you come to that conclusion, and what type of non-parallelism was it for? (BTW, MK and Wilson offer many of their blades in parallel versions, if you ask them.)

Oh, I see.  No, I don't use foam tape.  I use Scotch Magic Tape, as recommended by Bill_S.  I also apply mineral oil to allow the channel to slide easier.  Not sure how well foam tape on the sides of the channel would work in practice on a non-parallel blade:  could be difficult to maintain a smooth steady stroke because there is no clearance and the foam needs to compress/decompress as it slides along the non-parallel blade.  Centering would also depend on you holding the unit aligned properly throughout.  Sounds tricky to me.

I have no experience with intentionally non-parallel blades.  I had to do a piece-wise tape job on a Coronation Ace blade (nominally parallel blade) because of variations in the blade thickness (most likely from variations in the thickness of the plating, rather than the underlying steel).  No longer a problem since I switched to Auroras.