How skate blades are made

[Query]

I tried to find a tour of the HD sports factory, which makes makes JW and MK blades on Youtube, to see how blades are made. Didn't quite find exactly what I wanted.

https://www.youtube.com/watch?v=TpIAH0ewYY0 is as closed as I found. I thought they had gone completely over to computer-guided work (CNC), but it looks like there is still a lot of hand work.

JW and MK each have a Youtube channel:

https://www.youtube.com/channel/UCqF40hdTGubyXfJ_y1XOvYw

https://www.youtube.com/channel/UCgP6ttUM98_67pDVKB7_CxA

But there is more fluff than real information.

Jackson Ultima has a little.

https://www.youtube.com/watch?v=XGD4ZoaLp5w

Many places say the highest end Jackson Matrix blades are made from 440C stainless steel, and in the past Jackson advertised that they used it, but Jackson Ultima's current catalog now says they use AUS8 or 420J steel on some blades, and don't specify the steel in others.

(Side note: Matrix Advanced and Apex series use Titanium plating, and "tapered runners" - what some of us have called dovetail cut side honing.)

Paramount gives a fair bit more

https://www.youtube.com/watch?v=txUexBiGdoU

(Paramount says their blades are made from a single sheet of metal - which is different than I and others thought, and that I therefore have misstated on this forum. I thought the runner and chassis were glued together. That's interesting.)

As I noticed before, Paramount's claims about other brands contradicts info found elsewhere, such as Jackson Ultima's own catalog (about composition), and they selectively pick models and individual units when doing comparisons that make Paramounts look much better. However, that video came out in 2015, so is out of date, so some contradiction is to be expected.

But I haven't found the details of skate making I hoped for. Sigh.

Anyone found more?

[tstop4me]

(Paramount says their blades are made from a single sheet of metal - which is different than I and others thought, and that I therefore have misstated on this forum. I thought the runner and chassis were glued together. That's interesting.)

You're confused here.  The entire blade is not made from a single piece of metal.  Paramount blades are made from an aluminum-alloy chassis and a steel runner (two pieces total).  The chassis is fabricated from a single piece of aluminum alloy:  not a separate heel plate, a separate sole plate, and a separate body all attached together (that's a key point of the video). The runner is fabricated from a single piece of steel (Paramount uses 1085 plain-carbon steel, 420HC stainless steel, and 440C stainless steel).  As I wrote before, the Paramount website does not specify how the runner is attached to the chassis; but, I read their patent, and it specifies an adhesive.  There are no rivets, screws, or other fasteners.  I first thought attachment might be via a heat-shrink fit or a force fit; but, if their production process follows their patent, they're using adhesive.

[Kat]

Always interesting to learn some of the tech behind skates!

I didn't know MK and Wilson were the same company... I guess that explains why, say, the MK Pro and Coronation Ace are identical.  (In which case, why buy one over the other?)  Is this a case of, they used to be two separate companies but merged?  (Do they employ any women??)

I'm not sure how I feel about Paramount marketing their blades by knocking the competition...

[tstop4me]

Always interesting to learn some of the tech behind skates!

I didn't know MK and Wilson were the same company... I guess that explains why, say, the MK Pro and Coronation Ace are identical.  (In which case, why buy one over the other?)  Is this a case of, they used to be two separate companies but merged?  (Do they employ any women??)

I'm not sure how I feel about Paramount marketing their blades by knocking the competition...

MK and Wilson were originally two separate competing companies.  They merged in 1997 under the parent HD Sports.  The MK Pro and the Wilson Coronation Ace are not identical.

[FigureSpins]

I didn't know MK and Wilson were the same company... I guess that explains why, say, the MK Pro and Coronation Ace are identical.  (In which case, why buy one over the other?) 

They're not identical - the MK Pro stanchions are lower than the Coronation Ace.  They have different toe rake patterns as well.  It's just the rocker profile that is similar.

http://skatingforums.com/index.php?topic=8417

[Bill_S]

I bought both MK Pros and Coronation Aces a couple of lifetimes years ago and did a close comparison between them. Here's the thread about that...

http://skatingforums.com/index.php?topic=8417.0

I found that the Aces I bought then had a different rocker profile than my earlier 2007 Aces. I don't know if that was a production change, or just an unfortunate manufacturing glitch. I believe that the thread mentions the difference.

[Kat]

MK and Wilson were originally two separate competing companies.  They merged in 1997 under the parent HD Sports.  The MK Pro and the Wilson Coronation Ace are not identical.

Interesting.  I thought I had read they were essentially the same blade.

[tstop4me]

Interesting.  I thought I had read they were essentially the same blade.

They are similar in that they are both intermediate blades with 7 ft main rockers.  They are both fabricated from plain-carbon steel, and their overall construction is similar (for traditional models, separate heel and sole plates brazed onto stanchions). 

But for figure skate blades, the adage "The devil is in the details" applies with a strong emphasis.  As other members have pointed out, there are differences, e.g., in spin rocker profile, stanchion height, and pick pattern.  For some skaters, one or more of these details will make a substantial difference in their skating; for other skaters, perhaps not.

[Query]

You're confused here.  The entire blade is not made from a single piece of metal.  Paramount blades are made from an aluminum-alloy chassis and a steel runner (two pieces total). The chassis is fabricated from a single piece of aluminum alloy:  not a separate heel plate, a separate sole plate, and a separate body all attached together (that's a key point of the video). The runner is fabricated from a single piece of steel (Paramount uses 1085 plain-carbon steel, 420HC stainless steel, and 440C stainless steel).  As I wrote before, the Paramount website does not specify how the runner is attached to the chassis; but, I read their patent, and it specifies an adhesive.

You are right. They clearly show the entire blade chassis, in early stage, with blade-holder, plates, , and say it was made from a single extrusion. I was fooled, because it looks in the final shot of that like the lower part of the holder is thinner - but, in retrospect, that haven't added the runners yet.

I think they are oversimpify the modern Jackson Matrix fabrication technique. In particular, I am pretty sure the new Jackson Matrix blades also use adhesive. Certainly in the screw threads, possibly also to hold the holder and runner together.

I am rather puzzled that the British government let MK and Wilson merge under the HD Sports label. They were at the time the main competitors in the high end figure skating blade market. Doesn't the UK have antitrust laws? They act as though there are now no major competitors - they keep raising the prices, big time, on their most expensive blades.

I really wish someone would give them more competition. For a while, it seemed like Jackson would, when they produced the Jackson Matrix 1 blades, with interchangeable runners. The runners "only" cost $130/pair (still pretty expensive), if I remember right. And they worked pretty well, even though you had to be very careful not to strip the (probably) aluminum bolt heads and threads.

But then Jackson Matrix went to non-interchangeable runners, and stopped making runners for Matrix I holders, and upped their prices to be in the same ballpark as MK and Wilson. Leaving those of us who had purchased the Matrix I blades stuck.

(I had planned to explore many types of blade styles at that somewhat reduced cost. But immediately after I bought one pair of blades, they stopped making them, so I quickly, and without a lot of thought, fearing they would run out, bought out Rainbo Sport's supply of Dance runners in my size - though it turned out that Matrix Dance were quite a lot different than the MK Dance I was used to - and also bought one pair each of Synchro and Supremes. The Supremes turned out to be beyond my skill to use - toe picks too aggressive.)

(I did try to modify a pair of Matrix Dance runners to match the MK Dance rocker profile - but I wasn't happy with the result. MK Dance also had thinline ground edge widths, and imitating that would have been my minimal shop skills.)

I wish another company would make interchangeable runner figure skates, at a reasonable price, and offer more-or-less clones of the rocker profiles and edge widths of the most popular styles from other companies - so we could all inexpensively experiment to find the best style for each of us. I think they should also have separate interchangeable toe picks, that could be added and played with. Even if that company couldn't do the highest quality metallurgy, it would have helped each of us find what we best liked.

I notice Cricut makes sewing cutters that guide where the cut occurs - basically low end CNC. If there were a home-sharpening machine that would do the same thing - have a grindwheel that was guided by a computer to cut a user-specified rocker profile and toe pick shape - at a few hundred dollars (it needn't be as fast and powerful as commercial sharpening machines), and someone sold blanks, we could experiment that way.

(There are European cross-cut skate blade sharpening machines that are computer guided somewhat like that as far as the profile is concerned. But I think they are designed for the heavy duty fast pro shop market, and they are quite expensive.

Oh well.

I assume, as far as the high end blades are concerned, HD Sports must know a lot about metallurgy, and that no new cheap blade company could match them. In part, because when people make their own high quality steel knives, they often start with discarded used MK Sports skate blades.

[tstop4me]

I am rather puzzled that the British government let MK and Wilson merge under the HD Sports label. They were at the time the main competitors in the high end figure skating blade market. Doesn't the UK have antitrust laws? They act as though there are now no major competitors - they keep raising the prices, big time, on their most expensive blades.

I really wish someone would give them more competition.

That's not the way I see it.  I bought my first pair of figure skates in the late '60s, right after my first high-school summer job.  MK and Wilson were pretty much the only games in town for the US (here I'm not including blades used on pre-mounted, low-end boot/blade kits).  These days, I can choose from MK, Wilson, Ultima, Paramount, Eclipse, Skate Science, and Step (perhaps others I'm not aware of).

MK and Wilson, of course, are the entrenched defaults, well-known by generations of coaches, skate techs, and skaters.  Any new competitor would have to offer either comparable value quality/features at a lower price, or better value quality/features at the same, lower, or reasonably higher price; here, "value" "quality/features" and "reasonably higher" are determined by the skater.  I have no idea what the market share of each manufacturer is.  But if any newcomers have been unable to unseat MK/Wilson, that's their own fault.  I can think of substantial mis-steps by each, including MK/Wilson.

Figure skate blades seem to be too narrow a niche market for Japanese manufacturers.  They could certainly up-end the market, as they have done in high-end knives, machine tools, cameras, autos, ....

I assume, as far as the high end blades are concerned, HD Sports must know a lot about metallurgy, and that no new cheap blade company could match them. In part, because when people make their own high quality steel knives, they often start with discarded used MK Sports skate blades.

That's not the way I see it here, either.  I drop in now and then on knife forums.  People who make their own knives are mostly guys; and those are usually far too macho to be messing around with figure skates  .  And, if you were strongly interested in making your own knife, you would likely sneer at the low-grade steels that HD Sports use (where "low-grade" is relative to the exotic steels that knife fanatics crave).

It's typically the other way around:  Members of skating forums ponder what they can do with their stash of used blades.  Suggestions have included door handles, coat hooks ... and, knife blades.  But skate blades are hardened and tempered only in a limited zone near the edges.  If you've worn out the blade, you've probably exhausted most of the zone.  In which case, if you want to make a decent knife blade out of a used skate blade, you'll also need the knowledge and equipment to properly harden and temper the knife blade after you've fashioned it.

I also think HD Sports has been behind the competition in their choice of steel.  Until recently, they have clung obstinately to traditional plain-carbon steel.  Only with the recently introduced Wilson Phoenix line have they offerred stainless steel runners.  And here (according to their website https://www.johnwilsonskates.com/phoenix), they have selected an unspecified "420 stainless steel variant"; whereas, some competitors are using superior 440C and comparable (though, as I've pointed out before, the end result depends heavily on mechanical and thermal processing, as well as the starting material).

[FigureSpins]

Don't forget that retailers make money from selling specific brands.  The mfgs who offer the most income to the pro shop owner can become the "only game in town."  Plus, it simplifies the pro shop owner's life and helps keep inventory carry costs down.

You have to offer more profit or really tick off a retailer to have them select a new brand.  Riedell's recent back order delays are triggering some movement in that area, allowing Edea and Risport to pick up more retailers.  (One of my skaters waited over three months for a stock boot order to be completed.  This was before the pandemic.)

[Query]

In which case, if you want to make a decent knife blade out of a used skate blade, you'll also need the knowledge and equipment to properly harden and temper the knife blade after you've fashioned it.

I was once told (but can't verify) by someone who sharpened blades for Riedell (before they brought out their own line of blades) that the hardened steel extends a few mm upwards from the top of the chrome relief zone on chrome plated high carbon steel blades from MK. Very few people try to remove the chrome plate above that zone - it would be very hard to do so symmetrically, and by the time you wear above the zone, you need substantial toe pick surgery to keep the blade working well. Also, even if that was true, it might not all be of equal hardness.

I once corresponded with someone who was trying to make his own skate blades. He may have had some background for it - not only did he sharpen his own blades, but he worked at a steel mill. I asked him a question about tempering and hardening steel, based on Youtube videos I had seen about blacksmithing, where the blacksmith heated steel till it glowed red, then quenched it. He said that would only work for some steel alloys - that different steel alloys harden and temper at different temperatures.

Mike Cunningham once told me he was brought on a tour of the MK plant (I think this was before they merged with JW). As far as I remember, he said they used electrochemical means to temper the blade, then re-harden the edges blades, over a period of several days. Though that could be out of date now, and it is possible they didn't show him the whole process.

To what extent is hardening, tempering and re-hardening the edge on steel blades a black art? I.E., are there well defined recipes that show you how to do it optimally for each alloy, or are there still trade secrets?

Hmm. Based on the Paramount video, the material costs of skate blades, even for the most expensive skate blade alloys (like 440C), is far, far less than the price the blades are sold at. So if figure skaters wanted to recycle their used blades as scrap metal, the metal isn't worth much.

[Kaitsu]

Here is some blade brand what I didn't know before. I could assume these blades are out of many of us budget.

https://www.rolanddg.com/en/blog/190411-yamaichi-special-steel-develops-figure-skating-blades-with-olympic-skater
https://kozukablades.com/#product

[Bill_S]

Very interesting! Machined from a solid billet - that is truly expensive to do. The expense comes from both the skate material, most of which gets turned into chips, and the machines required to machine them.

It's interesting that they used steel instead of stainless steel.

[tstop4me]

Very interesting! Machined from a solid billet - that is truly expensive to do. The expense comes from both the skate material, most of which gets turned into chips, and the machines required to machine them.

It's interesting that they used steel instead of stainless steel.

<<Emphasis added.>>

There's probably two reasons why they don't use stainless steel.

* The first is cost.  A Paramount video [(https://www.paramountskates.com/videos) "Manufacturing" at 5:00 to 6:00] discusses the costs of various steels.  There is no date on the video, but it goes back to at least 2014 when I started looking at options for new blades (too lazy to hunt for current pricing).  The prices quoted then were $10/lb for 440C stainless steel and $7/lb for 420HC stainless steel vs only $0.89/lb for 1075 plain-carbon steel. 

With traditional manufacturing, the parts of the blade are cut from plate of suitable thickness, and I would not expect the cost of the feed stock to be significant relative to the overall manufactured cost.  But with the new Japanese monobloc process (https://www.rolanddg.com/en/blog/190411-yamaichi-special-steel-develops-figure-skating-blades-with-olympic-skater):

"A steel block weighing more than 10kg (left) is carved out with a milling machine (center), to create the finished product (right) that weighs just 270g, or around 2% of the original block."

That's a hefty chunk of metal (costing a corresponding hefty chunk of change) for each blade.

* The second is ease of machining.  I would have thought that they would have at least initially used an abrasive saw to rough out a T from the rectangular block.  But the article indicates that they use a CNC milling machine throughout to fabricate the finished blade from the rectangular block.  Stainless steel is susceptible to work hardening.  Such substantial milling (to put it mildly) would require relatively slow feed rates.

[Query]

I assume they don't throw away the milled steel. Perhaps they melt or otherwise re-form it into another billet?

Would that change your mind about the relative cost of using stainless steel?

Is it easier or faster to mill non-stainless steel? Could that be a significant reason?

Or could it simply be that the particular factory has more experience with the type of steel they are using? I have been told that metallurgy is a very complex art, so it might take a significant amount of time and experiment to change materials.

[Query]

Are figure skating blades still hardened, tempered and then edge-rehardened?

In
  http://www.iceskateology.com/Skateology/COPLANAR_SKATEBLADES.html

Sid Broadbent indicates that over the years, MK transition through at least three manufacturing phases in how (high end) blades were were shaped, to create the rocker profile:

  1. Stamp cut (i.e., a thin very hard shaped form is rapidly pushed through the sheet metal)
  2. Water cut (i.e., a thin very high pressure jet of water cuts through the sheet metal)
  3. Laser cut  (i.e., a high intensity laser cuts through the sheet metal)

(Am I using "sheet metal" correctly? Broadbent actually uses the term "steel sheet".)

The first two, like the milling process that Yamaichi indicates, are essentially mechanical, so perhaps the tempering was done partly to make that possible or better, faster and/or cheaper.

But perhaps laser cutting can be done on fully hardened steel?

I have read descriptions of how swords are made, that discuss a similar hardening/tempering/edge re-hardening cycle. The idea seems to be that tempering prevents the blade from fracturing on impact, which is a problem that very hard material can have. The edge itself is perhaps re-hardened so that it isn't cut through by the opposing sword, and also retains its sharpened edge longer.

I have read similar descriptions for high end kitchen knives, such as those designed to cut bone. Perhaps a somewhat similar reasoning applies.

But figure skating is typically done on relatively soft ice. Perhaps the impacts aren't hard enough to bother with the last two stages (tempering and edge-hardening), now that blades are laser cut? Or maybe, there is more hardened steel now?

If so, I and others have been repeating false information on the problems associated with removing too much metal from blades. In particular that you eventually reach soft metal, that will need more frequent sharpening.

Is there any way to easily tell? The devices that measure hardness are specialty equipment, that it might be none of you have access to.

[tstop4me]

I assume they don't throw away the milled steel. Perhaps they melt or otherwise re-form it into another billet?

Would that change your mind about the relative cost of using stainless steel?

Scrap steel or scrap stainless steel, particularly in the form of shavings, chips, or dust, won't get you much relative to what you initially paid for the rectangular block. 

ETA:  The Yamaichi website (https://www.yamaichi-hagane.jp/en/) indicates that they are a supplier and fabricator of steel, but they themselves are not a producer of steel.

Is it easier or faster to mill non-stainless steel? Could that be a significant reason?

I already addressed this above:

* The second is ease of machining.  I would have thought that they would have at least initially used an abrasive saw to rough out a T from the rectangular block.  But the article indicates that they use a CNC milling machine throughout to fabricate the finished blade from the rectangular block.  Stainless steel is susceptible to work hardening.  Such substantial milling (to put it mildly) would require relatively slow feed rates.

[tstop4me]

Here is some blade brand what I didn't know before. I could assume these blades are out of many of us budget.

https://www.rolanddg.com/en/blog/190411-yamaichi-special-steel-develops-figure-skating-blades-with-olympic-skater
https://kozukablades.com/#product

From the first link, this was the motivating reason for the monobloc design:

"What are the features of Kozuka Blades?

Ishikawa: With conventional skating blades, the base parts that mount to the boots and the blade parts are welded together by hand, which naturally results in slight individual differences between blades. Kozuka Blades are based on 3D data and are made from a solid steel block using a milling machine to create a single-piece blade. The resulting features are exceptionally high quality and strength with light weight."

Of all the shortcomings of traditional blades to be addressed, I didn't think the number one priority would be the joints between the stanchions and the mounting plates.

* I'm not sure whether they are using the term "welded" in the strict technical sense.  All the better grade traditional blades I'm familiar with use brazing for the joints.  I have seen some el-cheapo kit blades listed as having argon welded joints. 

* Some older write-ups have stated that select advanced models of MK blades were hand brazed with bronze; though I never found that directly stated by MK themselves.  Most blades I believe use silver braze (also sometimes referred to as silver solder or silver weld by some manufacturers).  Modern brazing is often done with an induction coil, rather than a hand-held torch.

* Has anyone (especially the skate techs here who handle many blades) come across problems with the joints between the stanchions and the mounting plates?  E.g., either in terms of misalignment or failure?

[Kaitsu]

* Has anyone (especially the skate techs here who handle many blades) come across problems with the joints between the stanchions and the mounting plates?  E.g., either in terms of misalignment or failure?

Take a look this videos and pay attention to the heel plate. Blade had failed brazing. => https://youtu.be/jJcNrhtiIEI  & https://youtu.be/KIDnw7AQPd0

Precision blade honing enterprises does have very nice photos from the cracked blades. => http://precisionblade.com/index.php/how-to-maintain-your-equipment/

I have seen couple times that blade runner was brazed or welded so that it was some degrees tilted, means it was far from the 90 degrees angle. I have also heard from the blades where one of three (most middle) stanchions was out of line, which was leading the situation that blade was twisting when it was mounted to skate holder and they had problems with blade straightness.

I have picture from the very old Phantom blades which I believe have been hand brazed. They have very massive brazing compared today's blades.

[Query]

tstop4me: I take it you think they cannot simply re-melt and re-freeze and roll (or otherwise form) the milled steel scraps to create a new steel sheet of the same composition. If I understand correctly (and I might not), they would also have to re-harden it (e.g., allow it to cool in a way that forms the right type and size of carbide inclusions). They say the do heat treatments, so maybe they can do that. Or is the initial freezing and hardening process more difficult than what a heat treatment plant would do? Or is rolling into constant thickness sheet steel require very expensive equipment?

BTW, there are some interesting quotes at

  https://www.rolanddg.com/en/blog/190411-yamaichi-special-steel-develops-figure-skating-blades-with-olympic-skater

What did you focus on the most during development?
Ishikawa: Our primary focus was to make blades that are comfortable to use for each skater's body type. To withstand shocks when landing jumps, we used a special steel that is flexible to better resist bending and impacts, but which also has high-strength characteristics.

It occurs to me they didn't choose stainless steel partly because they wanted these characteristics, and they knew them to be present in the particular steel they chose. Likewise, at one point, MK or JW or HD Sports said they used a "spring steel".

We heard that skaters often injure themselves when holding the blades while spinning or during other moves, so we designed them with bevels machined into edges that skaters can safely hold with their hands.

AFAICT, most skate techs "deburr" (eliminate the sharpening burr or lip) by drawing a flat stone along the edge at a slight inward angle to the side of the blade.

Do you think that is what they mean? Or do they mean that their edges aren't very sharp? E.g., perhaps they machine the edge in two steps, so that instead of one included angle, there are two... If the latter, it might exceed the abilities of most skate techs and their sharpening machines to maintain that beveled edge.

It's also possible the passage wasn't translated clearly. Between the difficulties of translating things accurately, and the fact that blade manufacturers often hide manufacturing trade secrets for competitive reasons, it might be inappropriate to read too much into what they say.

[tstop4me]

tstop4me: I take it you think they cannot simply re-melt and re-freeze and roll (or otherwise form) the milled steel scraps to create a new steel sheet of the same composition. If I understand correctly (and I might not), they would also have to re-harden it (e.g., allow it to cool in a way that forms the right type and size of carbide inclusions). They say the do heat treatments, so maybe they can do that. Or is the initial freezing and hardening process more difficult than what a heat treatment plant would do? Or is rolling into constant thickness sheet steel require very expensive equipment?

*  The scrap will likely be contaminated with cutting oil (and other muck).  So the contaminants need to be removed.

*  For heat treating 440C stainless steel, the maximum temperature is about 1065 C; whereas the melting point is about 1483 C.  So the furnaces need to achieve higher temperatures to melt the scrap.

*  During heat treatment of metals, the metal stays in the solid state.  When you melt a metal, it becomes a liquid.  Special equipment and processes are needed to handle metal in the liquid (molten) state.

*  Just as heat treatment of solid metal requires specific controls of atmosphere and thermal profiles to achieve the desired properties, turning molten metal into a solid metal requires ***different*** specific controls of atmosphere and thermal profiles to achieve the desired composition.

[tstop4me]

It occurs to me they didn't choose stainless steel partly because they wanted these characteristics, and they knew them to be present in the particular steel they chose. Likewise, at one point, MK or JW or HD Sports said they used a "spring steel".

As other blade manufacturers [e.g., Jackson Ultima, Paramount, Riedell Eclipse, Skate Science, and even Wilson (in their latest Phoenix blades)] have demonstrated, if you pick the right grade of stainless steel, and if you harden and temper it properly, you can achieve the proper characteristics in stainless steel.

[supersharp]

The beveled edges on the Kozuka blades are not on the sharpened side of the blade, they are on the upper side of the blade where you grab it for various positions (between the sole and the runner). It's a nice idea, the square contour of most blades can be quite uncomfortable. 

[tstop4me]

Take a look this videos and pay attention to the heel plate. Blade had failed brazing. => https://youtu.be/jJcNrhtiIEI  & https://youtu.be/KIDnw7AQPd0

You've lost me here.  I don't see how either video discloses a failed braze joint.