Can you use ceramics to sharpen s30/90/110v or not?

[Obsessed with Edges]

ToddS veers yes. FortyTwoBlades disagrees. Cliff Stamp in response to this very thread also says yes. HeavyHanded says no. I say yes and BluntCut MetalWorks probably disagrees. Conclusions and interpretations are all over the place

Simplest way to find out, is to use them. In actual use, the shortcomings of ceramics (i.e., aluminum oxide ceramics in particular) become obvious on high-wear steels. To some degree, they're capable of 'sharpening' steels with high vanadium content, and most people would likely be happy with that; but they just won't take it as far as a sufficiently harder abrasive (cbn, diamond) can do, nor can they do it with as little effort expended, and in as little time. It's more easily seen when directly comparing results and ease of sharpening on each of the abrasive types in similarly-rated grit sizes. Take a fairly dull edge in a high-vanadium steel (S30V, etc), and try to restore it with something like a medium Spyderco ceramic, and then try it with something like an EF (1200) or finer diamond. The differences will be obvious, in terms of how sharp it'll finish up and in how much (or little) time it takes to do it; not to mention, how little additional cleanup of burrs is needed. And a diamond hone won't suffer for it, like a ceramic that becomes glazed & polished with repeated use on steels with carbides harder than the ceramic can handle.


David

 

[FortyTwoBlades]

What is your favorite steel?
or best steel that could still be fully sharpened on ceramic

Literally any steel that has less vanadium carbide content than S30V. S30V is sort of the start of where you run into the sharpening issues associated with using high-vanadium steel in a knife, and so while the issues caused by it are also seen least in that particular steel compared to those with even higher vanadium carbide, they still show. But aluminum oxide is harder than chromium carbide, and much harder than plain low-alloy steel.

 

[Mikeg9]

Literally any steel that has less vanadium carbide content than S30V. S30V is sort of the start of where you run into the sharpening issues associated with using high-vanadium steel in a knife, and so while the issues caused by it are also seen least in that particular steel compared to those with even higher vanadium carbide, they still show. But aluminum oxide is harder than chromium carbide, and much harder than plain low-alloy steel.

Will Cpm 3v have any of the the problems mentioned ?
Thanks

 

[Mattysc42]

Will Cpm 3v have any of the the problems mentioned ?
Thanks

In my experience, yes. I tried to reprofile my 3v pendalton mini hunter from 20dps to 15dps on an 80grit ceramic belt (wsko blade grinding attachment) after 6 hours I gave up. Took it to my wicked edge 80grit stones and had it reprofiled in less than half an hour. I've found the edge holds up a lot longer against cardboard after sharpening on diamond over AlOx when the finish is 1000grit. I'm definitely curious about other people's experiences though.

 

[FortyTwoBlades]

http://zknives.com/knives/steels/cpm_3v.shtml

http://zknives.com/knives/steels/s30v.shtml

You can see in a comparison the CPM 3V still has a whole bunch o' vanadium. Basically just think to yourself: does it seem plausible that there's enough vanadium in this steel to form a bunch of vanadium carbide? If the answer is yes or "probably", then you may find that you get your best results finishing on a superabrasive like diamond or CBN.

 

[maximus83]

ToddS veers yes. FortyTwoBlades disagrees. Cliff Stamp in response to this very thread also says yes. HeavyHanded says no. I say yes and BluntCut MetalWorks probably disagrees. Conclusions and interpretations are all over the place

That much I got , except the Cliff info is new. Thanks for that. I'd still be interested to hear @Todd S. say what he believes all these extremely cool pictures are specifically proving, regarding the OP question. To me, the interpretation is everything.

 

[HeavyHanded]

To be clear, I never said you couldn't, actually:

Answer to the OP question - NO, not really. But if its all you have it will do OK.

It works, just not as well as using super abrasives. IDK what people are observing when they say there is no difference, how the added wear resistance from the carbides would have no effect on the abrasive action of sharpening tools does not stand to reason.

The photos from ekretz and my own observations (and observations of others) have convinced me completely. You can sharpen D2 and 154CM on Arkansas stones, but switch to a manufactured stone and the results improve notably. The same principle applies to the much tougher Vanadium carbides and the need for another step up in the abrasives needed to work them. I've used a smooth steel on D2 and gotten good results but is not anything I'd claim "works well" in a general sense.

To anyone interested in this, do your own testing. Make sure you are comparing as close across grit values as possible. Draw your own conclusions.

 

[maximus83]

I've already observed this same principle at work, not with sintered ceramic, but with their close relative, AlOx stones. My Arctic Fox stone will get my S30v knives really sharp. But the finish on the blade looks REALLY weird, sort of shiny and blotchy. When I switch over to diamonds, I can get just as sharp, and the appearance of the edge smooths up even on a DMT coarse plate. There is DEFINITELY something going on there.

 

[FortyTwoBlades]

Similar to what HeavyHanded said, I definitely didn't say it's impossible to use ceramics to sharpen S30V--merely that it's going to produce sub-par results vs. using superabrasives for your finishing stage. During your initial stages you can use aluminum oxide and silicon carbide stones for shaping work, and even for producing a nearly-finished edge, but anything too soft to abrade the vanadium carbides will experience greater wear to the abrasive particles (possibly causing glazing in hard-bond stones if insufficient pressure is used to cause the abrasive to shed) and you may experience premature blunting. If using ceramic on S30V I would only be using it for the lightest of light touch-ups or as the very final passes after having first dressed the bevel with a fine diamond (or similar) stone to properly abrade the carbides, using the ceramic only to crisp up the apex.

 

[maximus83]

Similar to what HeavyHanded said, I definitely didn't say it's impossible to use ceramics to sharpen S30V--merely that it's going to produce sub-par results vs. using superabrasives for your finishing stage. During your initial stages you can use aluminum oxide and silicon carbide stones for shaping work, and even for producing a nearly-finished edge, but anything too soft to abrade the vanadium carbides will experience greater wear to the abrasive particles (possibly causing glazing in hard-bond stones if insufficient pressure is used to cause the abrasive to shed) and you may experience premature blunting. If using ceramic on S30V I would only be using it for the lightest of light touch-ups or as the very final passes after having first dressed the bevel with a fine diamond (or similar) stone to properly abrade the carbides, using the ceramic only to crisp up the apex.

Let's assume for sake of argument that this is true. This means Spyderco's entire sharpening strategy for their end users to maintain their fancy steel folders--the Sharpmaker--essentially isn't working that great. To me, that's not new news, but a lot of Spyderco fans will disagree I'm sure.

 

[ToddS]

The OP's question can only be answered subjectively - everyone will have a different definition of "sharpen well enough."

Anecdotally, Shapton "ceramics" like the glass stone I used in the images above, work well enough for the way I maintain my blades. If I had to reprofile a few of these, I might have a different anecdote.

The only point I'm trying to make with the above images is that aluminum oxide can and does abrade vanadium steels and carbide "pop-out" or "tear-out" is not occurring. Wear resistant doesn't mean wear proof.

I have one last example, the same S30V blade before and after steeling with a smooth ceramic rod. I'm not going to suggest that this is the best way to maintain a blade, but it does show that even a dollar store ceramic rod can overcome vanadium carbides. (I'm probably poking another hornet nest in pointing out that steeling removes metal, it doesn't re-align the edge)

 

[HeavyHanded]

Let's assume for sake of argument that this is true. This means Spyderco's entire sharpening strategy for their end users to maintain their fancy steel folders--the Sharpmaker--essentially isn't working that great. To me, that's not new news, but a lot of Spyderco fans will disagree I'm sure.

Spyderco makes diamond and CbN rods, and not all of their offerings are super steels.

 

[HeavyHanded]

(I'm probably poking another hornet nest in pointing out that steeling removes metal, it doesn't re-align the edge)

I'm not sure I'd describe a ceramic rod as a "steel". Steeling does remove metal with exception of smooth meatpacker's steel.

 

[FortyTwoBlades]

A further note is that even in the absence of carbide tearout, one would still be essentially blunting

The OP's question can only be answered subjectively - everyone will have a different definition of "sharpen well enough."

Anecdotally, Shapton "ceramics" like the glass stone I used in the images above, work well enough for the way I maintain my blades. If I had to reprofile a few of these, I might have a different anecdote.

The only point I'm trying to make with the above images is that aluminum oxide can and does abrade vanadium steels and carbide "pop-out" or "tear-out" is not occurring. Wear resistant doesn't mean wear proof.

I have one last example, the same S30V blade before and after steeling with a smooth ceramic rod. I'm not going to suggest that this is the best way to maintain a blade, but it does show that even a dollar store ceramic rod can overcome vanadium carbides. (I'm probably poking another hornet nest in pointing out that steeling removes metal, it doesn't re-align the edge)

The larger issue in the case of sintered ceramics, given how little material they remove, is that due to their total lack of grit-shedding capability, that the abrasive grains on the surface will be prematurely worn and lead to glazing, in which case you'll then be doing little more than burnishing edges until you recondition their surface, which hardly anyone does (even though they should.)

A likely outcome of the slow abrasion of vanadium carbides by the softer abrasive is that you'll end up creating a more rounded surface with a greater angle to them than the surrounding steel, which may also have less-than-optimum effect.

 

[FortyTwoBlades]

I'm not sure I'd describe a ceramic rod as a "steel". Steeling does remove metal with exception of smooth meatpacker's steel.

Specifically, smooth "steels" are referred to in industry as a "slick". And yes, properly cut and hardened steels are essentially like files with their teeth running laterally around the rod.

 

[FortyTwoBlades]

Let's assume for sake of argument that this is true. This means Spyderco's entire sharpening strategy for their end users to maintain their fancy steel folders--the Sharpmaker--essentially isn't working that great. To me, that's not new news, but a lot of Spyderco fans will disagree I'm sure.

The Sharpmaker and their ceramic stones are really for light touchups and apexing, which they're fine for, even on high carbide steels. They've never really been a player in the market for shaping and refining stones, just apexing/maintenance ones.

 

[Obsessed with Edges]

Let's assume for sake of argument that this is true. This means Spyderco's entire sharpening strategy for their end users to maintain their fancy steel folders--the Sharpmaker--essentially isn't working that great. To me, that's not new news, but a lot of Spyderco fans will disagree I'm sure.

Spyderco's Sharpmaker was likely originally aimed at the 95% of the knife-using market who may never be willing to spend the big $$ on high-wear, supersteel, vanadium-heavy knife blades. The Sharpmaker's been around for quite some time, from mid-1980s onward, since before a lot of the modern vanadium-heavy steels became popular for use in cutlery (most of those steels were originally created for other uses). So, it's not like it was deliberately aimed at a usage target ill-suited for the tool. It's just that the Sharpmaker's original end-use wasn't likely intended for such steels in the first place, and probably couldn't have anticipated the need for sharpening such steels anyway, in consumer-grade cutlery. If you look at what Spyderco was using for blade steels in the period after the Sharpmaker was introduced*, you'll see most of their 'supersteel' knives were in steels like ATS-34/ATS-55, GIN-1, VG-10, etc., all of which are fairly wear-resistant due to chromium carbide content (maybe molybdenum carbide too), and NOT so much due to vanadium carbide content. As such, the ceramics of the tool were well-suited to the steels being marketed by Spyderco at the time.

That being said, I don't think their sales of it have been harmed all that much anyway, even now; AND, they've since introduced the optional diamond/cbn rods to make it more useful with a wider range of steels.

* - Edited to add:
Interesting tidbit I'd forgotten... The Sharpmaker was actually invented & marketed BEFORE Spyderco designed or made knives of their own.


David

 

[BluntCut MetalWorks]

My interpretation might be off or wrong ... I see this crater slightly weakened/compromised the apex above this location. Just a pure curiosity on sharpening stroke byproduct - how to produce a steel-stroke(rod against bevel) scratch lines almost parallel to stone-stroke line (about perpendicular to apex). Where I expect at least 10+ skewed degrees.

Keep in mind, impact can & will have negative result with severity depend on extent combination of higher hrc (less plasticity) and more acute angle. Fixed ceramic cutting points often dull and glazed, translated to higher impact component (both compressive & lateral), could lead to visible damage and or compromised steel subsurface (search rail track vs metal wheel).

 

[maximus83]

Wow this thread is great, this is why I enjoy being a member at BF. Lots of great insight here around all facets of this issue! A few replies, lumped together.

Spyderco makes diamond and CbN rods, and not all of their offerings are super steels.

Yep agree, they have have these options which would address the super steels, that's their answer to this problem. Still, I'm a long-time SM user, and have extensively used on super-steels all the ceramics including the UF, and the diamonds (haven't tried the CBN, but I've read here and in Spyderco forums, and Cliff Stamp, the sharpening experience and results are similar). The diamonds are not efficient for significant profiling work, so that type of sharpening task is not a serious option with these diamond rods. I found the diamonds were not even that great to work with for just maintaining an edge on standard s30v or s35v blades, although they do work and will cut metal with enough time, patience, and consistent sharpening strokes. Due to the coated nature of the abrasive, they are extremely bumpy and difficult to maintain a smooth continuous stroke across the bevel. I've seen other users post similar experience. Lapedog recently posted similar in some thread. The question is not whether they have an option for sharpening super steels (they do), or whether those can cut metal (they do), but whether they really work well given the coated nature of the abrasive. Feedback from a lot of users, including me, is mixed on using the diamond (and I'd bet, the CBN as well) rods. So basically, we're back to this reality: for maintaining your super steel blade with Sharpmaker, you are faced with either using these mediocre-performing and hard-to-use coated diamond/cbn rods, OR using the ceramic rods which we're saying here in the thread, are not optimal either.

The Sharpmaker and their ceramic stones are really for light touchups and apexing, which they're fine for, even on high carbide steels. They've never really been a player in the market for shaping and refining stones, just apexing/maintenance ones.

Yes, totally. This is the unique--and valuable--ongoing role I see for Sharpmaker. But for it to play this role, it seems like the vast herd of users who are using these would benefit from having this understanding of what it can do well, and what it can't. And, based on what we're saying in this thread, folks ALSO really need to adjust their sharpening strategy quite a bit based on the steel. For the OP, if set on using Sharpmaker to maintain, it should be diamond/cbn rods to do minor edge repair and apex, followed by extremely light finishing passes on one of the ceramics to refine the apex.

A related item that has some bearing on this: there are aftermarket companies making rods that fit in the SM holder, and use different materials that can cut these super steels. I wonder if these are worth investigating, for users who want to use SM with super steels, and want an improved sharpening experience over the diamond/cbn rods. Example: Congress Tools sharpening stones. I've seen a number of their stones referenced by Spyderco forums, for example the Ruby ones and the Moldmaster SiC stones. You can get these in a 1/2" triangle shape which will fit the SM slots, in a variety of very coarse grits, and these stones are only around $5 a piece. These would easily cut super steels. I wonder if users needing to maintain super steels with the SM could investigate these Congress stones as a solution, where the strategy is use these to edge repair and apex, use light touch on the ceramics to finish.

Spyderco's Sharpmaker was likely originally aimed at the 95% of the knife-using market who may never be willing to spend the big $$ on high-wear, supersteel, vanadium-heavy knife blades. The Sharpmaker's been around for quite some time, from mid-1980s onward, since before a lot of the modern vanadium-heavy steels became popular for use in cutlery (most of those steels were originally created for other uses). So, it's not like it was deliberately aimed at a usage target ill-suited for the tool. It's just that the Sharpmaker's original end-use wasn't likely intended for such steels in the first place, and probably couldn't have anticipated the need for sharpening such steels anyway, in consumer-grade cutlery. If you look at what Spyderco was using for blade steels in the period after the Sharpmaker was introduced*, you'll see most of their 'supersteel' knives were in steels like ATS-34/ATS-55, GIN-1, VG-10, etc., all of which are fairly wear-resistant due to chromium carbide content (maybe molybdenum carbide too), and NOT so much due to vanadium carbide content. As such, the ceramics of the tool were well-suited to the steels being marketed by Spyderco at the time.

That being said, I don't think their sales of it have been harmed all that much anyway, even now; AND, they've since introduced the optional diamond/cbn rods to make it more useful with a wider range of steels.

* - Edited to add:
Interesting tidbit I'd forgotten... The Sharpmaker was actually invented & marketed BEFORE Spyderco designed or made knives of their own.


David

David that all makes sense about SM being designed before the advent of super steels. They've tried to address the gap with diamond/cbn, but as many folks who use these know, they haven't quite nailed that part of the equation yet. At least, not IMHO as a user. I certainly don't attribute the lack of an "optimal" solution to super steels to anything sinister on Spyderco's part, they did after all release the diamond and cbn rods years ago to address this very thing. It just seems like they haven't worked that great. Also, I don't think most Spyderco average users have these add-on stones anyway, plus they don't realize that the included ceramic stones have the limitations with super steels that we're discussing in this thread. It seems like, for things to get better for those using SM to maintain super steels, they need some kind of improved strategy (best driven by Spyderco) to message HOW they should deal with super steels, and also, improved sharpening rod options. Absent that, it seems like SM users might be able to fall back on a solution something like what I indicated above in my reply to 42, some aftermarket stones that may cut better than the diamond/cbn, and then just using the ceramics in a very limited/niche role for light finishing work.

 

[Lapedog]

Wow this thread is great, this is why I enjoy being a member at BF. Lots of great insight here around all facets of this issue! A few replies, lumped together.



Yep agree, they have have these options which would address the super steels, that's their answer to this problem. Still, I'm a long-time SM user, and have extensively used on super-steels all the ceramics including the UF, and the diamonds (haven't tried the CBN, but I've read here and in Spyderco forums, and Cliff Stamp, the sharpening experience and results are similar). The diamonds are not efficient for significant profiling work, so that type of sharpening task is not a serious option with these diamond rods. I found the diamonds were not even that great to work with for just maintaining an edge on standard s30v or s35v blades, although they do work and will cut metal with enough time, patience, and consistent sharpening strokes. Due to the bonded nature of the abrasive, they are extremely bumpy and difficult to maintain a smooth continuous stroke across the bevel. I've seen other users post similar experience. Lapedog recently posted similar in some thread. The question is not whether they have an option for sharpening super steels (they do), or whether those can cut metal (they do), but whether they really work well given the bonded nature of the abrasive. Feedback from a lot of users, including me, is mixed on using the diamond (and I'd bet, the CBN as well) rods. So basically, we're back to this reality: for maintaining your super steel blade with Sharpmaker, you are faced with either using these mediocre-performing and hard-to-use bonded diamond/cbn rods, OR using the ceramic rods which we're saying here in the thread, are not optimal either.



Yes, totally. This is the unique--and valuable--ongoing role I see for Sharpmaker. But for it to play this role, it seems like the vast herd of users who are using these would benefit from having this understanding of what it can do well, and what it can't. And, based on what we're saying in this thread, folks ALSO really need to adjust their sharpening strategy quite a bit based on the steel. For the OP, if set on using Sharpmaker to maintain, it should be diamond/cbn rods to do minor edge repair and apex, followed by extremely light finishing passes on one of the ceramics to refine the apex.

A related item that has some bearing on this: there are aftermarket companies making rods that fit in the SM holder, and use different materials that can cut these super steels. I wonder if these are worth investigating, for users who want to use SM with super steels, and want an improved sharpening experience over the diamond/cbn rods. Example: Congress Tools sharpening stones. I've seen a number of their stones referenced by Spyderco forums, for example the Ruby ones and the Moldmaster SiC stones. You can get these in a 1/2" triangle shape which will fit the SM slots, in a variety of very coarse grits, and these stones are only around $5 a piece. These would easily cut super steels. I wonder if users needing to maintain super steels with the SM could investigate these Congress stones as a solution, where the strategy is use these to edge repair and apex, use light touch on the ceramics to finish.



David that all makes sense about SM being designed before the advent of super steels. They've tried to address the gap with diamond/cbn, but as many folks who use these know, they haven't quite nailed that part of the equation yet. At least, not IMHO as a user. I certainly don't attribute the lack of an "optimal" solution to super steels to anything sinister on Spyderco's part, they did after all release the diamond and cbn rods years ago to address this very thing. It just seems like they haven't worked that great. Also, I don't think most Spyderco average users have these add-on stones anyway, plus they don't realize that the included ceramic stones have the limitations with super steels that we're discussing in this thread. It seems like, for things to get better for those using SM to maintain super steels, they need some kind of improved strategy (best driven by Spyderco) to message HOW they should deal with super steels, and also, improved sharpening rod options. Absent that, it seems like SM users might be able to fall back on a solution something like what I indicated above in my reply to 42, some aftermarket stones that may cut better than the diamond/cbn, and then just using the ceramics in a very limited/niche role for light finishing work.

Personally if I have a knife that needs reprofiling I don't do it myself. I take the knife to a professional sharpener. The one I take it to uses Japanese waterstones and does a great job on any steel I've brought him so far.

He can set the edge to be easier for fixing up on they sharpmaker. After he sets it I just maintain it sharp. He flattens out convex edges or uneven grinds. He could even set it to a 30 degree angle so it will work easily with the SM jig.