Spyderco soon releasing a CBN bench stone

M

maximus83

Joined
Nov 7, 2011
Messages
2,102
CBN Benchstone - Spyderco, Inc.

306CBN_Both.png


Spyderco is shortly planning to release their CBN bench stone. It will be 3" x 8" and dual-sided, with 400-mesh grit on one side, 800-mesh on the other.

This stone will not come cheap, preliminary listings I'm seeing on retailers who support this forum, as here, are running around $92.

I'm interested in most things Spyderco releases, and will most definitely try one of these eventually. This stone, with 2 useful grits one coarse and one fine, has the potential to become a primary stone in someone's sharpening toolbox. I'm currently using Spyderco's "Doublestuff 2" cbn field stone (which I've written favorable reviews for here at BF), and also their triangle cbn stones for Sharpmaker, which I just got a couple weeks ago and am still evaluating but initial impressions are very good. Spyderco is definitely starting to figure out CBN and that's great news for the sharpening community.
 
It's a useful size, and Lord knows I don't need another bench stone...but we shall see down the road if my resolve holds.

I look forward to reading reviews.
 
Advantages over an electroplated diamond plate? I imagine the same disadvantages apply I.e particle tear out etc.?
 
IMHO--the biggest measurable advantages I have seen listed for CBN over diamond are when it comes to grinding applications (think Tormek grinding wheels, for example). This article summarizes the differences well, but in short cbn is better at certain kinds of sharpening/grinding applications, because it resists heat better and minimizes the amount of grit particles that are released and leach into whatever is being sharpened.

For manual sharpening, I have not seen any earth shattering differences in my usage, and have not heard anyone else say that either. I think depending on how Spyderco manufactures these plates (coated vs bonded, etc), just as with diamonds, it will make a difference in how they work and how you use them.

But just as there are big differences between diamond plates (for example, think about the very big differences in finish you get between some of the Atoma plates, vs DMT, vs cheap Chinese-made diamond plates) in terms of the edges they produce, there will be differences with Spyderco's version of cbn. To give a real world example, the aggression of my new cbn Sharpmaker rods is higher than the diamond ones but that's mainly because they're new. But I also note that the cbn rods by varying pressure and angle on the stone, are able to produce a nicer finished edge than the diamond rods. The cbn at around 400 mesh the way Spyderco does it is extremely versatile, you can use it for everything from reprofiling to producing a finished edge. The Doublestuff 2 field stone at first I was very skeptical of, but later I got it and reviewed it here, now in fact it's my primary pocket stone that goes everywhere with me, it can sharpen 100% of my knives. If the new bench stone is as good as we hope, then having it with 400 and 800 mesh grits, will make it a pretty effective multipurpose plate. Would love it if Spyderco eventually release a DS 2 stone with the 400/800, and also 800 versions of the SM rods.
 
It's a over lay coating. Not dispersed in a matrix. A cause for tear out with diamonds. No thanks. DM
 
^Show me a sharpening stone that never wears out, sharpens all steels and requires no maintenance. I'm in! :D They all have drawbacks some aspect of wear: some dish and have to be flattened, some are subject to things like abrasive being broken off or torn out.

Even with that--my DMT plates for example have lasted 10 years and still work awesome. They never require flattening, they sharpen every steel I have, just set them on the table and go. Same will apply to CBN. I'm not a pro sharpener using them heavily every day, I'm sure if I did, I'd be going through a new set every couple years or even sooner. And that'd be an acceptable cost of doing business, because 'maintenance' time on stones that dish, is ALSO a form of cost--my time. They're all tools and eventually wear out. I don't see this as a disadvantage, in fact IMO well made diamond plates have less disadvantages than other abrasive types, and more advantages especially the fact they can sharpen modern PM, high carbide steels effectively.
 
David Martin may well have a point. Mine has been on preorder since about 10 seconds after it was announced, though, and I have no inclination whatsoever to cancel the order. I want to check the thing out.

I have some CBN metallic bonding stones to compare with, so if it is bad, I expect to know fairly soon. But if it is, it will be the first Spyderco product ever that inspired disappointment. So I am sanguine.
 
UncleBoots said:
if it is, it will be the first Spyderco product ever that inspired disappointment. So I am sanguine.
Click to expand...

Exactly, if this was first stone by an unknown company or even by Spyderco, I'd be more reluctant. In fact I was initially *very* skeptical as mentioned above back in 2017 when they came out with DoubleStuff 2 in CBN, and Sharpmaker rods, heard a couple negative reports at first, and the usual complaints you hear about these, DMT and similar, "OMG they're embedded in surface coating layer vs being resin-bonded, they're an accident waiting to happen and won't last more than a week."

I then heard feedback from people I respect on the Doublestuff 2, was so intrigued I found one on sale. Then I was so impressed, it got to the point that I stopped carrying my DMT diafold sharpeners for field use, all I carry now is the DoubleStuff 2, it's that effective. Only other field stone I ever bring is sometimes the 6" Arctic Fox field stone if I have machetes or choppers with me. After that, I took the plunge on the Sharpmaker cbn rods, same thing. It boils down to that the method of embedding the sharpening media on a plate may or may not be optimal in one's own experience and view. But....not all manufacturing processes are identical, some companies may take the same general manufacturing process and do it WAY more effectively than others (take the example of Buck's highly effective heat treat on 420 steel, making a lot of their 420 knives head and shoulders above most other 420 knives and the heat treat they use). Similarly with Spyderco, they're not perfect for sure and I had complaints about the diamond SM rods in the past for instance. But they do other things high quality, and so far what I've seen of their CBN, whatever process they're using to produce these coated stones/plates, they've got it dialed in.
 
I will only purchase stones if the grit matrix is a 1/2 thick. These last.
The platted format type don't last for me. For light use, ok. DM
 
Not really, but a resin-bond CBN hone with 1/2" of material on-board that is of any decent size would probably cost a big-boy sized fortune. Demand would be pretty low on that one I think.
 
Ok, I would settle for a 1/4" matrix with a good % in the mix.
Does cbn grit sheer off like diamond? DM
 
Last edited:
David Martin said:
Ok, I would settle or a 1/4" matrix with a good % in the mix.
Does cbn grit sheer off like diamond? DM
Click to expand...


In a general sense you could think of it as diamond is to Alox as Cbn is to silicon carbide. Not really, but Cbn has sharper corners and sides that are sharp enough to cut like a carbide cutter on a mill, whereas diamond is somewhat blockier more like Alox.

If Cbn is aligned well it cuts rather than scrapes. Talking to my father in law about it, he felt the best application is on a hard substrate like an iron wheel, with the Cbn in a thick slurry. Allowed to orient itself it will cut more with the edges - cleaner stock removal, less subsurface disturbance.

Bonded or plated to a hard surface it might still be slightly better than diamond for sharpening depending on the edge you're looking for.

From an industrial standpoint it is mostly better than diamond only because it tolerates higher grinding temps. Other folks might have more to say about the technical fine points.
 
From an industrial standpoint it isn't slightly better than diamond, it's generally far better than diamond - for its specific recommended purposes. For a cutting tool on hardened steel or iron diamond can't be used unless it's at an effective crawl. Diamond is still used rarely for very precise lathe turning in steel but only at extremely low speeds. If it's used at too high a speed and the temperature gets too high, the steel will dissolve the diamond and absorb it as carbon. As you can imagine, it doesn't take much change in dimension of the cutting tool to ruin a precision dimension. The same goes for grinding wheels. CBN cutting and grinding tools were developed for this exact reason, as it does not react in such fashion, and is nearly as hard as diamond.

If diamond can be used, there is no better, longer lasting material for abrading or cutting. It can be used freely at high speed on pretty much any non-ferrous material. However, the benefits don't always outweigh the cost in industry.
 
^Yes. See the article I linked earlier on benefits of CBN. Again, its benefits for grinding applications are mainly:
  • Withstands heat, especially during high-speed applications
  • Does not cause grit that can dull bits
  • Stays sharp and cool because it does not react with steel
Also BTW, note this interesting blurb at the end of the article, kinda' caught my attention with regard to future applications of cbn:
Nanotechnology and CBN

In January 2013 issue of Nature, a scientist from University of Chicago’s Center for Advanced Radiation Sources and his colleagues reported they had been able to make ultrahard CBN by drastically shrinking grain size. The researchers were also able to rearrange the crystals into a zigzag formation of boron and nitrogen rather than in conventional flat layers to give it super resilience.

“Now, we can make this material as hard as single crystal diamond,” says the lead scientist, Yanbin Wang. “In some ways, it’s a better tool than diamonds, especially given its high fracture toughness.”
Click to expand...

Now back to our world: I think for manual sharpening application, the first and third bullets above are mostly irrelevant. However the second point could be germane to DM's question, if Spyderco manufactures the CBN right and its well embedded on the plate, in theory during the process of sharpening it should not shed as much grit onto the steel being sharpened. Obviously the proof will be in the pudding there, it's never just a theoretical question of how CBN "should" do X or Y differently from diamonds, it's always in an actual implementation in a real stone that somebody makes. Because as we've all seen, you can't just generalize about how 'diamonds' work in all cases, you always have to look at a particular diamond plate: DMT, Atoma, Ultrasharp, somebody else, they have similarities, but all can work quite differently, wear out faster, produce a different finish, etc.
 
Ok, great. These 3 ^ make sense about how cbn is better than diamond when attached to a substrate. DM
 
You must log in or register to reply here.
Back
Top