News:

Equipment Issues?  Talk about them in our Pro Shop:
http://skatingforums.com/index.php?board=25.0

Main Menu

Wissota powered skate sharpener review

Started by Bill_S, November 04, 2019, 06:55:19 PM

Previous topic - Next topic

0 Members and 6 Guests are viewing this topic.

supersharp

More on the old IE discussion...

Since the rocker at the front of the blade is a smaller radius, the blade height is changing the fastest there.

As you move the blade holder along the guide rod from right to left, as the blade moves from front to middle, the distance between the holder and the wheel will increase, tilting the blade away, thus removing more material from whichever edge is closer to the floor, and then the opposite happens as you continue from middle to end.

I had the best results overcoming the curvature bias in the old IE machine by:

-placing the blade in the holder so that the longer, flatter radius was lined up with the holder (of course not completely parallel, since one is straight and the other is a gentle curve)
-setting the blade height to be centered at the middle and back of the blade using witness marks, and noting where the left knob was located for being centered at the middle
-starting at the toe pick end, lowering the blade for centered contact right behind the toe pick, then progressively raising/turning the knob to keep it centered as I ground from toe to middle. With carbon steel, you can see where the blade is burning on the wheel, so you can almost see the center.
-it was not practical nor was it necessary to do any adjustment of the right knob (at the heel). My right hand was needed for consistent speed control and pressure, and my left was finessing the elevation in the rocker area and then just providing stability.

Needless to say, I practiced this on junk blades before I ever tried it on blades in use, and experimented with my own at first.  Risky in terms of the blade profile, to a point, because it is hand shaping, but it was the only way I could get level edges with a perfectly centered groove.  You can just as easily destroy the subtleties of the rocker radius with inconsistent pressure, and the parallel guide rod system does really help with keeping a light, even pressure.

If I hadn't converted my old machine to a new one, I'd send a photo of the difference between my technique and just running the blade through parallel.  Running through parallel put the groove slightly off-center either at the middle or at the toe and heel, and neither seemed acceptable because it affects the edge angles.  I love how Sid identified this problem and solved it.  It really is an elegant design.

With the new IE, the blade has double rods so it moves in and out without changing elevation. Spendy conversion but I'm very happy with it. It will take me another half-season of sharpening to cover the cost of the upgrade (less hours on the ice this year so less sharpening, so I guess it wasn't good timing financially) but I don't mind because I have been wanting to make this upgrade for 10 years.  I usually use my sharpening income to help pay for going to skating camp, so I guess it kind of evened out with no camps in 2020.

Good equipment is a delight. Worth it.

tstop4me

This thread has forked from a discussion of the Wissota machine to a discussion of the Incredible Edger (IE).  I'll leave it to the admin whether to separate the posts.  Meanwhile, since we have two people here with first-hand experience of the IE, I'll post my question here, rather than launching a separate thread.

Around 5 years ago, when I was considering buying a sharpener, I did consider the IE.  But, a local pro shop, specializing in figure skates, had one, and I was not happy with the results.  Background:  the owner not only is a tech with many years of experience, but also a coach and former competitive and pro skater; so he knows how important a good sharpening is.  He sharpened traditional Coronation Aces for me several times.  This is a straightforward blade for sharpening:  plain-carbon steel, parallel sides; no stainless steel, taper, side honing, or thick chassis to be concerned about.

Traced profiles showed good rocker control; and HDI measurements showed good control over ROH and centering (level edges).  But there were substantial chatter marks along the entire length of the blade.  These were not due to lack of dressing, because he dressed the wheel right before the sharpening (he let me watch).  And it wasn't anything peculiar about my blades;  all the blades he sharpened were like that.  He told me that it was purely cosmetic; after all, he said, many skaters he coached (and whose skates he had sharpened) had competed at regionals, sectionals, and even US Nationals with the chatter marks.  But I've had Coronation Ace blades sharpened on other machines, and the finish was far superior.

He felt the problem was that the IE uses a low-torque motor, which requires a light touch (low pressure) between the blade and wheel.  This is good for minimizing material removal and overheating, but bad for chatter.  When he applied higher pressure to reduce the chatter, the motor was prone to stalling (this was on a scrap blade, not mine!). 

Have the two of you (Kaitsu and supersharp) encountered this problem?

supersharp

Coronation Ace is a very straightforward blade to sharpen. And I disagree that the chatter marks are only cosmetic...more discussion below.  Was that tech a skater? 

I think most of this is basically true for all machines:

Definitely more chatter marks with the medium wheels than the fine. Speed of pass-through has a significant effect, both for the blade and for dressing the wheel. I experimented with dressing the wheel at different rates and different numbers of passes and feel like it needs multiple slow passes to really be smooth and it needs at least 2 slow passes after adjusting the knobs to create a consistent, centered hollow (each time you move a knob, you are changing the location of the center of the radius).  I check the radius at multiple points after I check the edge levelness.  You can have one without the other, so the only way to know both are right is to check both.

The wheel also gets smoother with use, so I dress it at the start and it glazes over a bit as I sharpen, making it smoother on the final passes. Adding wax also makes it smoother, but then the next blade takes a lot longer to get sharp. Depends on the skater and situation as to whether this is necessary.  I rarely use wax.

Unless the belt is loose, applying enough pressure to bog down the motor sounds like way too much pressure, but maybe it was a coarse wheel?

I do a couple of long slow passes as I'm finish to get as smooth of a machine finish as possible (I use the fine wheel) and then deburr and final polish the edges by hand. I have skated on the final product as my technique has improved over the years, so I can give first-hand feedback:

~Guy who trained me—no deburring. Pretty sure he used a medium wheel to save time. Yikes. Be careful stopping and don't cut yourself wiping snow off your blades.
~Early days—I added simple deburring because why wouldn't you? I hated those nasty ragged edge bits.
~Old IE with curvature bias reduction technique —definitely more consistent edge angles along the whole blade.
~Previous...with addition of polishing chrome relief with gummi stone/cratex stone—mmmmm, nice.
~Previous...plus ceramic rod honing to deburr and extend edge life—definitely smoother, but a little too sharp so needed to hone then dial back the edge a hair or it took too long to get used to the sharpened blades. Edges seem to last longer, though, which extends blade life. 
~Previous...plus polishing the radius with garnet cloth wrapped over an appropriate sized dowel chunk—starting to feel pretty amazing.
~Previous...plus use of new machine where my focus doesn't have to be split between curvature bias reduction and speed—probably slight improved speed control. Overall, very brief adjustment period and really nice smooth edges.

What other skaters notice the most:  polishing the chrome relief, polishing the ROH, and sharpening the NSZ if it has been left flat (probably only matters when the flat is >3/4", doesn't need to be sharpened every time, but it's best if the edges are level; see other discussion on NSZ).

Would love to see a response from Kaitsu.

tstop4me

Quote from: supersharp on April 03, 2021, 08:11:34 PM
Was that tech a skater? 
As I mentioned above, the tech is also a coach, and a former competitive skater (hi-level elite) and a former pro skater (including well known ice shows).

Query

Quote from: Kaitsu on March 31, 2021, 02:32:35 PM
In Ingredible edger you can use wheels up to 2 inch size. As I am living in country where we have 50Hz electrical network, I am loosing 20% of the speed compared to 60Hz network.

Slightly off-topic, but an electrician who worked on a lot of motors, especially sub-pumps, told me that it is very important to match the voltage and frequency that feeds a motor to the motor's spec.

If you don't, the motor windings may get very hot, and burn out.

Anyway, it may be worthwhile to get the frequency adjuster installed sooner than later. But make sure it creates a sinusoidal voltage and current output at full load - harmonics pump extra electrical energy into A/C motors, which is partly dissipated as heat rather than producing mechanical power - and 5th harmonics typically produce a reverse torque in A/C motors, which fights the rest. I don't know how you check for sinusoidal output, but he when he wasn't trying to be fancy, he verified that a mean-responding current meter, and an rms-responding current meter, gave the same result.

I'm not an expert in this, and he was only an electrician, not an engineer, but this is what I vaguely recall he said:

It has something to do with how long the motor stays in "start mode". In particular, A/C motors, like fluorescent lights, when they start up, typically draw a lot of extra current. I don't know all the details - e.g., whether there is always internal circuitry, or whether it is sometimes a natural result of induction, etc.

(In addition, an A/C motor is to an extent a rotating inductor. It's impedance creates a different resistance to current flow at different speeds. E.g., when power companies create summertime "brown outs", lowering the voltage because they are near their maximum power output, he said he found that power draw by the University actually increased - probably because air conditioning motors draw more average power at lower voltage. However, he said it might "work" a little over the long run, because a lot of those air conditioners burned out, because the motors got too hot.)

There were other factors which influenced that, like alignment between the motor and pump, the mount positions within the range of travel of the linkages, motor and pump balance (most electricians are not trained as mechanics, yet are often told to maintain or replace motors),  various ways of reducing startup water pressure on the pump (never put pumps in series to increase pressure - let each pump push water up to a well at atmospheric pressure instead; drill a pin hole into outflow pipes a foot or so over the outflow), proper lubrication, poor electrical voltage/current conditioning (such as harmonic components from switching power supplies, such as are in computers and UPSs), the incorrect wiring diagram that came with some motor control systems that used A/C for power and D/C current for control on the same line (half the diagrams left out the diode), inappropriate transformers, insufficiently large wires (creating voltage drops), the discrepancy between code current ratings (American motor companies do not rate motors by their mean or maximum current draw. They rate them by the size of the "overload breaker" that should be used to prevent burn out if the motor overheats for any reason. Most electricians don't know that. As with other appliances, they over-rate the breaker by at least 25% (I think), so the windings burn out before the breaker reacts.), the University's tendency to go with the lowest bidder ( :) ), and other things.

When he started working at the University of Maryland, which had over 200 buildings with sub pumps, some of the sub pumps would fail every few weeks. Once he figured things out, by a combination of trial and error plus having discussions with the better motor shops, a master plumber, and the engineers who designed the motors and transformers, all of the motors he had installed within the past 30 years were still working. So these kinds of things, including voltage and frequency, may make a significant difference.

Obviously you should use a transformer if your voltage is off by more than a few percent.

It is common for low end motor shops to compensate for minor voltage and frequency differences by shortening the wire in the windings. That increases the current, which overheats the wire, and the motors don't last long. A rule of thumb used by the shops that maintained motors with fewer problems was that you should simultaneously increase the size of the wires used in the windings, so that the total mass of the metal was about the same.

He was once given a Japanese motor to install, with a very high reliability rating, designed for a different voltage and frequency, to install, that had been bought at a a discount. The buyer was very proud; he thought he was saving a lot of money, and was buying quality. It fell on the electrician I knew to prove him right. The electrician had an "unlimited master's license", and had no trouble finding a transformer to compensate for voltage. But he had to get together with a high end motor shop to re-engineer the motor. In the long run, it would have been much cheaper to use an American motor designed for American voltage and frequency.


supersharp

Quote from: tstop4me on April 03, 2021, 09:24:15 PM
As I mentioned above, the tech is also a coach, and a former competitive skater (hi-level elite) and a former pro skater (including well known ice shows).

Oops, missed that, thanks. Interesting. So many layers to this topic.

Sometimes these things like smoothness, modest twist, are just less of a problem to a highly skilled skater who can compensate for anything being imperfect.  My coach can skate on pretty much anything, probably a couple of shelf brackets on some tennis shoes, haha, although she of course prefers a good blade on a custom boot. Having to compensate isn't a big deal to her at age 33 having skated her whole life.  I find the older skaters, even some of the stronger skaters, pay a much higher price for contorting themselves to make up for mounting or sharpening problems.  When you already know how to do something, you can rely on body memory and your brain can focus on fixing the glitches, maybe? 

I have a friend who very gracefully skates at a snail's pace when working on new skills and she really needs her equipment to do everything it can.  She is 70 and started skating at age 52, and I will bend over backwards to fix whatever allows her to skate for as long as she can.  Even the tiniest thing affects her because she skates slowly, but she can't speed up unless everything feels perfect.  A pro skater may find the chatter marks immaterial, but for the slow adult skater it might make the difference between stalling and achieving some actual flow.  It's all about experiencing some joy on the ice, really, and fortunately that is shared by all of us, regardless of speed and skill level. I can still remember learning back swizzles and it was pretty much The Best Thing Ever because I was skating BACKWARDS. It just made me so happy.

Kaitsu

First at all, my sincerely apologies that we were messing with IE related discussions in thread which was meant to be just for Wissota. Bill has made great review of Wissota and I agree that we should have own thread where to discuss about the differences of the big wheel and small wheel machines. I am bit novice, so I would like to ask your help to contact moderator to split IE conversations to own thread. Its nature of mine to jump from topic to another :) My apologies also if my English inst so good!

Wissota is excellent machine. A bit heavy and too big wheel to my taste, but this is just matter of opinions and personal needs. I guess its a fact that possibly 98% of figure skates are sharpened with big wheel machines. Also blade manufacturers uses big wheel machines. So I am not trying to say that Wissota is crap and IE is the best machine on the markets.

When I decided to invest to new sharpening machine, I had three options:
* Wissota (was cheapest and machines were available in local agent stock)
* Blademaster BRPD1G with 3 inch wheel. European model was not in stock and delivery time was ~2 months. (Model seems not to be available anymore)
* Incedible Edger

I did choose IE for following reasons:
* I need portable machine
* I had machine with 6" wheel and I wanted to have machine with smaller wheel
* During the years I haven't seen any single video or read users experiences from the Blademaster 3" portable machines. I was scared to be first one :D
* I was a bit scared about the friction of the table...even it can be tuned by polishing and waxing

To be honest, in the beginning I was disappointed to IE. I used so much money to it by believing that I will immediately get superb surface finish. It took couple years to learn all tricks to get surface finish what you did see on one of my posts. Picture what I shared from the retailers quality witness that they are also suffering from the severe chatter. According to my experience IE and its fine grit wheels can produce good surface finish only right after the dressing the wheel. Already second pass-through creates clear chatter marks. Its not clear to me is it because of missing cutting speed, fine grits of wheel, the rotation direction of the wheel or something else. Anyhow wheel travels always over the grinding dust and it sticks also into the wheel. Wax glues even more this dust. When it happens, grits loses partly their sharpness and it will not cut the steel properly. So what I do is that I dress the wheel every ~10 pass to keep the wheel radius correct. When I feel that blade is sharp enough, I dress the wheel and make one more pass. After that I clean the blade, dress the wheel ones again and make last final pass with gentle pressure. Speed of pass-through has a significant effect to the surface finish like supershap mentioned. This is I guess is indication of missing rotation speed.

So yes, I agree that IE causes easily chatter marks, if you don´t know how to use it. I think there is couple reasons for that:
* smaller wheel = lower cutting speed, smaller contact area + less mass on the wheel
* Table top machines skate holders has wide contact to table and they should have basically zero clearance in that means, when IE does have very small contact areas in round guide reals. With four-point bearing system there is risk that only three bearing has proper contact to the rails. In my opinion IE is more sensitive for vibrations due its mechanical structure.
* If there is any speed hunting in the electrical motor, gear ration multiplies those problems into the wheel. So I think direct drive would be better than belt drive.

What I do not agree is that chatter would come from the missing torque of electric motor. If the wheel speed reduces while sharpening, problem is in the belt drive. Belts will not last forever and even the dust can make it to be slip even at lower grinding pressure. Cold ambient conditions makes belt slip even more easier. This I have noted when I sharpened skates on outside conditions also on winter time (due COVID). So yes, I agree that belt drive inst most optimal and you need to pay extra attention to it. Example belt tightness, cleanliness etc.

Electrical motor of mine IE is with the correct voltage. It is the frequency which drops the speed 20%. I am not electrician, but I am 100% sure that I will not overheat the electric motor as long I so not increase the frequency too much. I have not considered what would be the maximum frequency what I could use. Basic idea is increase the frequency from 50Hz to 60Hz when wheel is new. When wheel gets smaller, I should increase the frequency to keep cutting speed all the time same.

PS. I would like share my thanks Bill, Query and Supersharp about these interesting discussions. I have enjoyed from every moment.

Query

Quote from: Kaitsu on April 04, 2021, 08:40:39 AM
Electrical motor of mine IE is with the correct voltage. It is the frequency which drops the speed 20%. I am not electrician, but I am 100% sure that I will not overheat the electric motor as long I so not increase the frequency too much. I have not considered what would be the maximum frequency what I could use. Basic idea is increase the frequency from 50Hz to 60Hz when wheel is new. When wheel gets smaller, I should increase the frequency to keep cutting speed all the time same.

That is so clever! :)

Remember that altered frequency might mean less torque, because the induced force depends on the frequency, and because the motor was designed with the right time lags for a given frequency. So you probably want to use a light touch so as not to overload the motor. But you presumably already do that to get such a nice finish. And now that you have invested in such an expensive tool, you probably do that already to make it last longer. Of course professional skate techs have to balance that sort of thing against the economics of trying to sharpen as many blades/hour as they can, which may be why some of the busier shops buy $10,000 - $30,000 machines.

I wonder how wax compares to oil, polishing fluid, or jeweler's rouge, both in terms of how clean the edges are, and how clean the finish on the hollow is. And how much that affects skating.

Kaitsu

I believe electric motor what I have is 3-phase motor which is converted to 2-phase motor with capacitor. When I apply frequency converter, capacitor is removed and third phase is taken in use. It should bring some extra torque. Even I would be wrong in this  I am not so worried about the torque. But you are right, it drops if frequency converter cannot fix it.

Quote from: Query on April 05, 2021, 04:33:10 PM

I wonder how wax compares to oil, polishing fluid, or jeweler's rouge, both in terms of how clean the edges are, and how clean the finish on the hollow is. And how much that affects skating.

During the years I have tried so many different chemicals to improve surface finish. I have tried example, pure water, WD-40 + several other spay oils, Chemico valve lapping paste, ski waxes, Accu-Lube stick, Blackstone Fine Shine, metal polishing wax, etc. etc. Main conclusion has been that almost all of them improves less or more surface finish. They main issue is that most of the ingress very deep in to the wheel and you need dress quite much from the wheel before it gets clean. For this reason I prefer to use "cutting oil" which viscosity is close to water.

I know this is anyhow wheel type and size dependent. Example Blackstone Fine Shine didn't work in my IE, but in Blackstone and hockey skates it worked well. Its viscosity and consistency was very close to 10W-30 motor oil. I have to say that Fine Shine bottle was not mine own, so I cannot be 100% sure if content really Fine Shine or has the skate tech filled it by him selves.

Unfortunately I have quite many big projects ongoing so I could not make you comparison with / without polishing wax finishing. Here is anyhow link to picture where I sharpened one pair of skates by using different polishing wax on both blades. In right foot blade used wax which is for aluminum and left foot blade I finished by using wax which is for silver and gold. I could not identify any differences on the surface finish. If you can see some differences in the pictures, it is impossible to say if they are from different view angle, light reflection or camera´s own adjustments. I should have some fixture which would ensure that pictures from left and right foot has been taken as identical setup as possible. Even this is not 100% perfect test, I can confirm that polishing wax was not bad at all. It is not anyhow going to be something what I use.

It is recommeded to download the picture so that you can zoom in to different areas of the blades.
https://www.dropbox.com/s/0alp5m8ev5aobnu/Polishing%20wax%20test%20IE%4050Hz.jpg?dl=0

What comes to the surface finish, I would say that its quite obvious that chatter-marks and coarse grinding will not improve the glide. I have one skater whom used to bring his skates for me. From my proposal they started to sharpen skates in one another skate tech (due long distance). Skater was happy for his skates until they did come to competitions which were kept by our club. Father of the skater did see me on the rink and he asked if I would have time to sharpen their skates. There was some hassle why their skates were not sharpened well before competitions. I said that I can do them, but there is always risks if you change the skate tech just before your competition day. They said that skates are so dull that they rather take the risk than try to survive over the competition with the dull skates. In next day I asked their feelings about the skates. They said that skates glide is so much better that the speed what you can gain is almost scaring. I didn't change ROH, so mainly improvement did come from the better surface finish. Since that they have used again my sharpenings.

It is anyhow fact that quite many skaters don´t recognize any difference in the skates even you believe that improvement what you have made is so remarkable that skater should notice the difference already in the first stroke. This should not anyhow be any excuse for skate techs to make poor quality. Unfortunate fact is that too many skate tech makes sharpening s just to earn money and not to help skaters with best possible sharpening what they can do.

EDITED 11.4.2021
I tried some new mixture for another pair of Wilson blades. I was more satisfied to this new mixture than metal polishing wax. Link to new picture: https://www.dropbox.com/s/hhg7ihzeb7g7bjd/Polishing%20test%20IE%4050Hz%20-%20own%20mixture.jpg?dl=0

Query

Quote from: Kaitsu on April 10, 2021, 02:40:27 PM
In next day I asked their feelings about the skates. They said that skates glide is so much better that the speed what you can gain is almost scaring. I didn't change ROH, so mainly improvement did come from the better surface finish. Since that they have used again my sharpenings.

Cool!

I believe you that the finish helps.

I assume you know that effective sharpness is not just determined by ROH. Most skate techs use a flat stone to deburr or repoint the sharpening burr. The exact way they do that has a tremendous effect on effective sharpness (because most people round off the edge a bit when they use that flat stone) - which also affects speed, a lot.

Another issue: if you scratch the sides of the blade, on the part that touches the ice when the blade sinks into the ice a bit, that might increase friction. I am not sure how much that matters, but I try not to as much as I can.

Some people who sharpen straight razors use "polishing fluid", or jeweler's rouges, which I think contains very small grain abrasives, like diamond dust. Some skate techs use polishing fluid with fine abrasives in it while using powered sharpening machines. They say it improves the finish.

Quote from: Kaitsu on April 10, 2021, 02:40:27 PM
I believe electric motor what I have is 3-phase motor which is converted to 2-phase motor with capacitor. When I apply frequency converter, capacitor is removed and third phase is taken in use. It should bring some extra torque. Even I would be wrong in this  I am not so worried about the torque. But you are right, it drops if frequency converter cannot fix it.

There are many different types of three phase and 2 phase electric system, even just in the U.S. E.g., see

https://ctlsys.com/support/electrical_service_types_and_voltages

When the electrician I mentioned wasn't sure what to do, he sometimes called the motor manufacturer, and asked to talk to the engineer who designed the motor. They might be able to guess whether your system is set up right, and how to tell if the motor is overloaded and/or getting too hot.

Perhaps you have already done what needs to be done.

supersharp

Quote from: Kaitsu on April 10, 2021, 02:40:27 PM
In next day I asked their feelings about the skates. They said that skates glide is so much better that the speed what you can gain is almost scaring. I didn't change ROH, so mainly improvement did come from the better surface finish. Since that they have used again my sharpenings.


I had one skater (about 12 years old at the time) who brought me her skates after forgetting to have them sharpened for months after they needed it. They were very worn, edges were chopped up by blades hitting each other.  I sharpened them her father picked them up. The next time I saw her, I asked her how they felt. She said,"you know how it feels when you're riding your bike and you're in the wrong gear and it's really hard, and then you shift gears and it feels great?  It was like that."  What a great analogy.

Other skaters just say "they feel fine" when I am sure that there is a tremendous improvement in the blade. Some are just not very aware.  I agree that we should still provide them with quality work, but it is disappointing to restore a blade from bad to good and have the skater notice nothing.

I also report to the skater and coach if I see edges wearing unevenly. Worn down spin spot and edges still sharp—busted!  I have a friend who used to have this problem until I explained that her spin obsession was the reason.  Too many CCW moves and not enough CW—the edges always reveal the truth. Always stop with the same foot on the same edge—that one will probably get dull first.  Just like the tracings on the ice, there is evidence there, you just have to look for it. 


Leif

This thread is a very interesting read. I'll add a few comments which may be of interest.

A few years ago I looked to purchase a sharpener, and the Wissota was on my list. The price including shipping and UK tax was reasonable. Several issues put me off. The first issue was that it would go in an unheated garage, and Wissota warn against that. I didn't want it indoors because of metal and abrasive dust, and oil, given that I have carpets in the house. The second issue was that I wasn't convinced I could learn how to use it, when only sharpening once a week. Looks like I was wrong, given your experience. I do know someone who owns one, and he likes it a lot. I am surprised at the issues you had, hopefully Wissota are now aware of them.

Regarding BAT gauges, I had a ProSharp gauge that was off by several thou, unacceptable IMO. It disagreed with a no name ebay gauge, a Sparx gauge, and a BladeMaster gauge. I sent it to the office in America in disgust and they said it was within spec. I never did get a refund. It was painted, and I didn't think to check for paint build up. More recent ones are anodised, which avoids a paint problem.

In the end I bought a Sparx sharpener, which is excellent. However, it is more expensive to run as grinding wheels cost ~£70-80 and one wheel can sharpen ~ 80 pairs of skates assuming a light sharpen and no damage. So that is £1 a pop. If the blades are damaged, with deep notches in the edges, that will use up a lot of the grinding wheel, and be costly. Also it needs a different grinding wheel for each hollow, and that could work out expensive. A Wissota can do a range of hollows with the same wheel, just redresss it to suit. Of course one big advantage of a Sparx is that kids can use it without risking injury, and I leave it to sharpen a blade while I make myself a coffee. The only issue I have had is when sharpening cheap hockey skates. The steel blades were soft, and it really didn't get a great finish. They were probably okay, and it might have been due to cheap steel, in which case the Wissota might have done no better.

I was lucky as a friend gave me a collection of wheels including two unused 5/16" wheels! Those last two will go on ebay. I wear hockey skates and I skate on a 7/16" hollow. I may try a 3/16" hollow just to see how it feels. I am 11 stone 7 pounds (161 pounds), so quite light for a male.

Bill_S

Wissota's warning about using the sharpener in unheated areas comes without any mention about temperature thresholds that would cause the problem. To me, that's a little vague. That can cost them sales.

I'm an inveterate tinkerer, so tweaks to machines are inevitable once they arrive here. The most serious issue was fitting the dust hood to the machine.

I didn't contact Wissota about this, so it might be an ongoing issue. I do think that the dust hood (or other alternative) is essential even in a dedicated workshop like mine. The hood combined with the shop vacuum makes it a fairly clean, but noisy operation.
Bill Schneider

tstop4me

Quote from: Leif on August 17, 2021, 06:08:43 PM
....

In the end I bought a Sparx sharpener, which is excellent. ....

I wear hockey skates  ....

<<Emphasis added.>> A caveat for readers unfamiliar with previous discussions of home sharpeners on this forum.  Leif is a hockey player, and the Sparx was initially specifically designed as a sharpener for hockey skates. They have since introduced an adapter for figure skates.  I've not read any reviews of how well this adapter works.  But also note an FAQ on the Sparx website:

https://sparxhockey.com/pages/faq

"Can you sharpen figure skates?

Yes. We offer a figure skate adapter for $99.99. With the figure skate adapter in place, Sparx can sharpen most traditional, flat-sided blades. Sparx is not compatible with the multiple-piece blades often used in competitive skating."

So the figure skate adapter at most will handle traditional blades with flat, parallel sides (such as standard Coronation Ace), but not traditional blades with other geometries such as Gold Seal (concave side-honed, tapered sides) and two-piece (chassis plus runner) blades such as Matrix and Paramount.


supersharp

Re:  Sparx and figure skate sharpening

With the replacement cost of good figure skating blades as high as it is, I can't imagine using this kind of automated process on anything above basic recreational skates. It's designed for hockey blades and probably does an adequate job on that continuous curve...but putting a high-quality figure blade into it? 

Kaitsu

Few comments related to so called automated sharpening machines and Leif experiences related to the wheel costs...(my apologies that this is out of original Wissota topic)

In my opinion wheel costs in traditional wheels are not so much lower than in diamond coated wheels. If best possible surface finish is what you are intend to do, you have to dress traditional wheel quite often which means that also your dressing diamond will wear.

If we think about where diamond wheels are typically used, can you name any other metal grinding process which would use diamond coated wheels? Perhaps there is some reason why traditional wheels are still dominating in the metal grinding industry.

With my very less experience about the diamond coated wheels, I would expect that metal wheels which are coated with diamond grits are not suffering same weight balancing issues than traditional wheels. In the other hand what I have seen and heard with my ears (while hockey teams uses Prosharp SkatePal machines), diamond wheels will never provide same surface finish than what you can gain with weight balanced traditional wheel. You can hear already from the sound that blades are going to have heavy chatter marks and burrs on edges. It is also possible that this is just consequence of wrong use of machine, but so far all diamond wheel machines what I have seen has kept terrible noise when wheel hits to the blade.

When considering sharpening of figure skates with these automated machines, it's good to keep on mind few things...
* Even figure skates blades are parallel type, their thicknesses are not even and it the same time automated machines blade thickness adjustments are not so accurate. To be able to control if the edges are going to be even, you need to remove skate from the machine. Will the chromed blade position always similarly when you put it back is good question.
*You have adjustment for blade thickness, but not for parallelism. At least with my experience chromed figure skate blades where chrome has been partly removed requires always adjustment to get blade in level (parallel to axis / even edges)
* For the toe picks there are some protectors, but how to control that heel is not going to get rounded or grid too less?
* While you enjoy your coffee or tea, unpleasant surprise might wait when you were not controlling the machine. When blades costs 150-300£, it might be expensive cup of coffee / tea. (Referred to Supersharp)

In my opinion sharpening skates is not so scientist that it should be scared too much. Automated machine sounds like you cannot fail so easily with them, but I disagree that. Only thing you automate is movement and grinding pressure. All the other issues remain same as in manual work or even get more difficult to control. Every machine has their own tricks and you need to learn them anyhow by doing enough many skates and trying different things. Those are more difficult to learn than keeping grinding pass or grinding pressure equal all the way.

Bill_S

Doesn't the carbon of diamond dissolve into the steel at the temperatures created by powered grinders? That leads to the diamond breaking down quickly.

Instead of diamond, use cubic boron nitride (CBN) for grinding steel if you don't want to use standard wheels. Because CBN abrasive particles are embedded in a metal wheel for grinding, they can't be dressed to different ROH.

Just Google the phrase "why not diamond wheels for grinding steel" to find more.
Bill Schneider

supersharp

Quote from: Bill_S on August 25, 2021, 02:07:25 PM
Doesn't the carbon of diamond dissolve into the steel at the temperatures created by powered grinders? That leads to the diamond breaking down quickly.

Instead of diamond, use cubic boron nitride (CBN) for grinding steel if you don't want to use standard wheels. Because CBN abrasive particles are embedded in a metal wheel for grinding, they can't be dressed to different ROH.

Just Google the phrase "why not diamond wheels for grinding steel" to find more.

Excellent point and fascinating to read more about grinding wheels. 

From Kaitsu:
"In my opinion sharpening skates is not so scientist that it should be scared too much. Automated machine sounds like you cannot fail so easily with them, but I disagree that. Only thing you automate is movement and grinding pressure. All the other issues remain same as in manual work or even get more difficult to control. Every machine has their own tricks and you need to learn them anyhow by doing enough many skates and trying different things. Those are more difficult to learn than keeping grinding pass or grinding pressure equal all the way."

I agree, and there is so much information coming in through your hands as you move the blade across the wheel. I know I'm not a machine, so no doubt there is some variation in the speed across the wheel, but I think that is more than made up for by having a feel for what you are doing. I look at the contact point of the blade on the wheel and watch the blade move by, sort of a Zen moment where I feel like I'm observing the flow of the blade across the wheel and having that feedback go directly to my hands if I sense any disruption in speed. Long, slow passes require intense focus, so like skating itself, it takes you out of your thoughts and requires that you be very present in the moment.  I guess I like to think that I'm much more likely to notice if something isn't quite right, and would notice it sooner (preferably before the complete destruction of a nice blade).  I can enjoy my reasonably-priced cup of tea afterwards.


Sharpening Horror Story of the Week:  parent of a skater (approximately 13 years old, has been skating for about 4 years) contacts me to schedule a sharpening. She drops off skates. Later I prepare to sharpen them and see that the laces need to be replaced but the boots are in otherwise good condition.  Then I look at the blades. They are unsharpened to about 3 to 4 cm from the toe pick, meaning they have never been sharpened in that area. The blades are also very dull, and both are extremely off-level at the back. I can't image the misery of trying to skate on these!  So I send the parent a text asking if the skates are new to this skater. No, she apparently wore them all season last year and for the first few weeks of this season.  I ask who sharpened them last, parent said "oh, I only bring her skates to you". Hmmmmmm. I explained that I had never sharpened these blades before (I can tell because I always sharpen into the NSZ) and the response is along pause and then "oh, uhhhh, maybe they've never been sharpened?"

Apparently this skater skated an entire season on a factory sharpening. 


Query

Quote from: supersharp on August 28, 2021, 02:02:42 AM
Sharpening Horror Story of the Week... Apparently this skater skated an entire season on a factory sharpening.

A very bad factory sharpening! Which brand & type blade?

A video on "Cape Falcon Kayak" says, in relation to planes and chisels, that "tools don't come sharp". He also says that you frequently have to file some plane mechanisms to make them work well.

Is it your impression that new edge tools frequently need to be resharpened, and that many new commercial tools need minor adjustments? I recall Bill said his new Wissota needed minor modifications. Was that true for other Wissota buyers?


Bill_S

Quote from: Query on August 30, 2021, 10:42:05 PM

A video on "Cape Falcon Kayak" says, in relation to planes and chisels, that "tools don't come sharp". He also says that you frequently have to file some plane mechanisms to make them work well.


Yup. Search for "fettle a plane" to learn more. It's often squaring a plane mouth or smoothing burrs from the bed that are required. Sometimes more is needed. For example, I sent this Stanley No. 5 to a machinist to have the sides ground square with the bottom for "shooting" duty.  https://www.afterness.com/woodworking/planes/plane_stanley_no_5_tablesaw_tom-6-800px.jpg

Some of the better planes and chisels (Lie Nielsen, Veritas) may come acceptably sharp, but most users still sharpen the blades first for best results. The standard test is that you can shave hair on your arm with a well-sharpened chisel or plane blade. A user has to frequently re-sharpen after every few hours of use, so you can identify a serious woodworker by the lack of arm hair.  ;D
Bill Schneider

Leif

Thanks tstop4me for pointing out that I wear hockey skates, it was remiss of me not to mention that fact. Yes I can't say how well Sparx machines work on figure skate blades though they are compatible with some blades. ProSharp make a similar machine which as far as I can tell is for hockey skates only.

Quote from: supersharp on August 22, 2021, 12:21:49 PM
Re:  Sparx and figure skate sharpening

With the replacement cost of good figure skating blades as high as it is, I can't imagine using this kind of automated process on anything above basic recreational skates. It's designed for hockey blades and probably does an adequate job on that continuous curve...but putting a high-quality figure blade into it?

I'm curious why you think a Sparx (or similar ProSharp machine) only does an adequate job. Before I bought the machine I struggled with getting a good sharpening. Many sharpeners don't get even edges. I have also seen some appalling sharpenings of figure skate blades, such as uneven edges with right side high at the front and low at the back, and one case where the wheel had not contacted the full blade width, resulting in a stepped hollow! When I lived in Montreal I even saw figure skates with part of the pick ground off by a sharpener. My last blades before I bought a Sparx were almost flat. Uneven pressure during multiple sharpenings had significantly changed the blades' profiles.

Essentially a machine can get even edges and maintain the profile. I am not convinced a human can preserve the profile. No there is no chatter at all. The finish is excellent. I am a good skater as hockey players go (struggling with forwards inside edge three turns) and the Sparx is a god send. I'd recommend a figure skater get a Wissota or similar, having sharp blades that are correctly sharpened is worth the outlay. It also makes it easy to try different hollows, or change the hollow to suit the ice. That at least is something hockey players do.

Incidentally, ProSharp make automated machines that sharpen figure skates, I assume all kinds. The operator dresses the wheel with a diamond as normal, but the machine does the grind.

The one notable difference with a Sparx is the lack of oil on the last cut. Does anyone know if that makes a measurable difference when skating?

supersharp

When I said "an adequate job", I did not mean that as a slight against the Sparx in that context.  With no toe pick and a design that allows for rolling onto and off of both ends of a hockey blade, automating the process seems like something a machine could do adequately.  A hockey friend of mine has one and he loves to be able to create fresh edges before every game.  For the same pair (or several pairs) of hockey skates, it's seems like a good way to take control of your own edges and also be able to have the convenience of sharpening whenever you want. 

Sadly, it's true that there are many, many cases of poor sharpenings being done every day all over the world by people operating machines of all different types.  I've definitely seem some pretty awful examples and have seen a pair of brand new blades have half of their life removed in a single sharpening by a person who didn't know what they were doing.  But this doesn't mean that hand-operated sharpenings are worse by nature.  It depends on the skill, understanding, and attention of the sharpener. 

There are a lot of differences between hockey blades and figure skating blades, which is why I feel like the Sparx wouldn't work for me.  Figure blades generally have complex curvature at the front end; they have that oh-so-necessary but oh-so-in-the-way toe pick to deal with, and the back of the heel should not be rounded.  The blades are generally longer (for the same foot length...and I say "generally" because my dance blades are about the length of most hockey blades) and they are generally wider, with variation in thickness across blade models and types.  Some have dovetail edges.  Some have side-honed edges that are hand ground and not actually mirror images of each other (blade is shaped like an hourglass with the widest part along the sharpened edge to make a more acute angle for greater grip).  Some are parabolic down the long axis of the blade, so the front and back of the blade are wider than the center.  Most are carbon steel (a fair variety of types of steel of varying hardness), some are stainless.  All of these options add up to it requiring a lot more guidance in terms of where the wheel goes, particularly if you sharpen for a group of about 40 figure skaters like I do.  I'm not convinced that a machine like the Sparx can be a "one size fits all" type of sharpener.

The blades I sharpen run from $90 to $650/pair and all have to be ordered from out of town.  It would take a lot of sharpenings at $20 each to cover the loss from damaging even one pair of mid-range blades.  I like being able to see what is happening and control the level of pressure and where I start and end each pass. I can watch edges that are off-level changing to level one pass at a time, and can make fine adjustments that keep the process from removing excess metal.  I know my speed is probably not as precise as a machine, but I think it's reasonably good and there are a lot of other factors that make up for small variations in speed.  Since I am a figure skater, I know how it feels to have a good sharpening vs an okay one vs a bad one.  I want my skaters to have their edges kept in the best condition possible since skating is already hard enough without fighting your equipment.

I'd say there are additional considerations that Bill_S would be better at explaining in regards to the cutting properties of the diamond wheels and their use on carbon steel blades. 

As far as adding oil or wax on the last pass, my experience is that it does make a difference in the smoothness of the blade.  You can create a beautiful polishing pass by adding oils, but then your wheel needs to be re-dressed or the next skate you sharpen will get polished rather than sharpened. Hand tools can also be used to improve the final finish (something you could try after you use the Sparx, perhaps?) I'm still experimenting on this, it sounds like Kaitsu has had more experience and the photos of the final edge condition are gorgeous.

Does the effort of the final polish matter--I think that is in the eye (foot?) of the beholder.  If you don't polish a carbon steel blade, it takes a week or so of skating to smooth out the fine chatter enough that you have nice flow across the ice, which is disappointing.  Our rink sharpening machine (Blademaster with what I guess is a medium or coarse wheel) leaves the bottom of a carbon steel blades looking like tweed as compared to satin.  One coach had the rink sharpen her skates when she discovered there was rust on the blades when she arrived at the rink, and gave them to me to resharpen right after that ice session.  She said it felt like trying to skate through sand.  Newer skaters--I don't know if they would really notice, and they might actually find the extra resistance reassuring because it makes the blades a little less slippery.  I direct all the skaters with basic recreational skate blades to the rink for sharpening because they can't feel the difference yet and the toe pick is usually so high up on the front that  there isn't much issue with keeping the profile intact.  It costs half as much, and I don't think I'm really adding a lot of value to their experience at that stage. Plus I already work full time and skate...I don't want to end up spending my time sharpening instead of skating. The upper-level figure skaters love to be able to put on freshly sharpened blades and have that immediate flow, so the higher their skill gets, the higher the degree of polish I add.  I've experimented with my own blades and I have a strong preference for a beautifully smooth finish, but I doubt I would have been able to appreciate the difference in my first few years of skating.

tstop4me

Quote from: Leif on September 02, 2021, 06:24:16 PM
Incidentally, ProSharp make automated machines that sharpen figure skates, I assume all kinds. The operator dresses the wheel with a diamond as normal, but the machine does the grind.
<<Emphasis added>>  Yes and no.  ProSharp is a Swedish company.  A couple of years ago at my rink, we had a hockey coach who was originally from Sweden.  He brought over with him the then top-of-the-line ProSharp AS-2001 machine (there's a slightly improved current version that sells for ~US$11K).  I looked into what it would take for it to handle a full range of figure skate blades.  For plain vanilla blades (traditional blade with stanchions brazed onto mounting plates, and flat parallel sides), you just need to buy a stock attachment.  For more complex geometries (e.g., tapered, side-honed, and chassis+runner), however, you need custom clamping plates as well.

But even then, as Kaitsu previously pointed out, such automated machines assume that the clamping surfaces on the blade are parallel to the longitudinal axis of the blade.  And that assumption doesn't necessarily hold for many figure skate blades.  With a manual unit such as the Wissota, the skate holder has a 2-axis tilt correction capability; Sparx and ProSharp unfortunately do not.

supersharp

Quote from: Query on August 30, 2021, 10:42:05 PM
A very bad factory sharpening! Which brand & type blade?


Ultimate Mirage blade.  I was surprised because Ultima blades are usually close-ish to level, although the unsharpened space behind the toe pick is variable—1.25" to 2.5" (3 to 6 cm). 

tstop4me

Bill:  Could the Wissota unit operate with a 3" diam wheel?

*  What is the diameter of the mounting hole for the Wissota wheels?

*  Assuming a 3" diam wheel were installed, (a) Would the diamond dresser arm have sufficient reach? and (b) Would the skate holder hit into any obstruction?

*  The surface feet/min would be less with the smaller diam wheel, but that could probably be accommodated.  Any other issues you can think of?

I know you personally have not found any issues with the larger diam wheels.  Just curious whether the Wissota would work with a smaller diam wheel (assuming you could get one from a different supplier).