# Who wants to speculate



## Barmoley (Sep 9, 2020)

https://www.knifecenter.com/item/SP306CBN/spyderco-cbn-cubic-boron-nitride-bench-stone-sharpener-3-x-8-inch



So this looks cool to me because Spyderco usually makes good stuff and I've been wanting to try CBN stones for a while, but they were either not available or very expensive. I have a set of vitrified diamond stones that I am very happy with, but this looks like it could be a good, reasonably cheap option.

In any case what are the opinions of the collective?


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## Ruso (Sep 9, 2020)

Assuming mesh in this case translates to JIS 1:1 it is not the grits I am after. I would love to try it in something like 200/800 and 2000/5000.
But great for spyderco, and the price is very reasonable. Hopefully they will make more grits/mesh available.


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## Barmoley (Sep 9, 2020)

Ruso said:


> Assuming mesh in this case translates to JIS 1:1 it is not the grits I am after. I would love to try it in something like 200/800 and 2000/5000.
> But great for spyderco, and the price is very reasonable. Hopefully they will make more grits/mesh available.


I want more grits too, but 400/800 assuming JIS 1:1 is a reasonable first offer. I wonder how it will feel and how durable, long lasting it will be. They have a history of making CBN rods for the sharpmaker, so they are not new to it. Bench stone might be different though.


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## Luftmensch (Sep 9, 2020)

Could be good for fast removal. From the website description:



> this stone is also the perfect choice for sharpening wood chisels, plane irons, and similar tools



If you don't have a grinding wheel. Regrinding plane irons and larger chisels is laborious work. Maybe thats their market?

Interesting item! I'd be keen to hear more community wisdom...


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## JDC (Sep 9, 2020)

Holy moly


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## JDC (Sep 9, 2020)

Might be a good thinning stone, no idea how to flatten this, if it needs that.

Edit: "perfectly flat carbon steel embryo of this stone is coated with fast-cutting 400-mesh CBN on one side and finer 800-mesh CBN on the other" so no thinning needed, a diamond plate replacement.


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## Barmoley (Sep 9, 2020)

Talked to some very knowledgeable people and so far the consensus is that it is a product similar to DMT plates. If true won't need flattening but also will feel pretty bad and will be done once the CBN is worn off.


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## panda (Sep 9, 2020)

wonder how it is for thinning?


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## Kippington (Sep 9, 2020)

I've used CBN compound for stropping and found it to be crap compared to diamonds, but I guess that's a totally different from a stone.


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## Barmoley (Sep 9, 2020)

Kippington said:


> I've used CBN compound for stropping and found it to be crap compared to diamonds, but I guess that's a totally different from a stone.


I’ve heard really good things about vitrified and bonded CBN stones, but they are rare and expensive and also different from this Spyderco product.


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## Luftmensch (Sep 9, 2020)

Barmoley said:


> Talked to some very knowledgeable people and so far the consensus is that it is a product similar to DMT plates. If true won't need flattening but also will feel pretty bad and will be done once the CBN is worn off.



Or more like a vitrified diamond stone?


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## Barmoley (Sep 9, 2020)

Luftmensch said:


> Or more like a vitrified diamond stone?


Doesn’t look like it seems to be just a CBN coating similar to how diamond plates are. Metal plate coated with thin layer of CBN compound. Not 100% until someone tries it, but very, very likely.


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## Luftmensch (Sep 10, 2020)

Ahhh.... That wouldnt feel particularly nice!

Probably not much of an advantage on simpler steels (other than flatness). Could be good for high hardness, high-wear resistant steels (e.g. Rex 121).


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## kayman67 (Sep 10, 2020)

Kippington said:


> I've used CBN compound for stropping and found it to be crap compared to diamonds, but I guess that's a totally different from a stone.


What's the compound?


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## ModRQC (Sep 10, 2020)

If they ever do lower grits of these with lower price accordingly, perhaps it could compete well with an Atoma for flattening stones, too. I'd like to see that.


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## Kippington (Sep 10, 2020)

kayman67 said:


> What's the compound?


Can't remember, bought it 10 years ago.


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## lowercasebill (Sep 10, 2020)

Robot Check


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## lowercasebill (Sep 10, 2020)

It was an amazon link that failed. Go to amazon search cbn comes from Russia, .5 micron $17 USD


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## Barmoley (Sep 10, 2020)

Sounds like there are different types of CBN, so the experience might depend on which type you got, unfortunately it doesn't seem like you can tell what you get, so buying from a reputable source is the way to go. Also, looks like one of the benefits of platted CBN vs platted diamond might be that CBN adheres better to the metal plate and so doesn't get ruined as much by people using too much pressure. Apparently, this is how most diamond plates get ruined, by too much pressure when sharpening.


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## Ruso (Sep 10, 2020)

lowercasebill said:


> It was an amazon link that failed. Go to amazon search cbn comes from Russia, .5 micron $17 USD


Good CBN stones from Russia/Ukraine are quite expensive. Usually fair amount more expensive than diamond stones. I am talking abt stones here, not plates though.


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## lowercasebill (Sep 10, 2020)

Ruso said:


> Good CBN stones from Russia/Ukraine are quite expensive. Usually fair amount more expensive than diamond stones. I am talking abt stones here, not plates though.


I was not clear my post was in reference to stropping compound. I should have hit the reply tab . Apologies.


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## Barmoley (Sep 10, 2020)

Ruso said:


> Good CBN stones from Russia/Ukraine are quite expensive. Usually fair amount more expensive than diamond stones. I am talking abt stones here, not plates though.


Any links to these, very curious about bonded CBN stones. I am very happy with vitrified diamond stones, bit still curious.


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## Ruso (Sep 10, 2020)

From my research long time ago, Poltava seems to be the better ones. You can see them here. It’s only maker I could find that makes wide stones as well.
The prices are in Ukrainian Hryvnia








Эльборовые бруски на медно-оловянной связке в Москве от компании ""Инструментарий"".


Купить Эльборовые бруски на медно-оловянной связке в Москве - цены, товары и услуги компании ""Инструментарий"": +7 (930) 962-33-98 WhatsApp




e-instrumentariy.ru


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## kayman67 (Sep 10, 2020)

Unfortunately, even in Russia these are quite expensive. Just one grit equals ~4 double Venev plates/stones.


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## applepieforbreakfast (Sep 16, 2020)

Got an email back from Spyderco.

400 grit is 40-50 micron
800 grit is 14-28 micron

For comparison.


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## Ruso (Sep 16, 2020)

applepieforbreakfast said:


> Got an email back from Spyderco.
> 
> 400 grit is 40-50 micron
> 800 grit is 14-28 micron
> ...


Basically following JIS more or less. Thank you for sharing!


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## M1k3 (Oct 2, 2020)




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## Barmoley (Oct 2, 2020)

M1k3 said:


>



That’s cool. Shawn was one of the people I asked about these when I started this thread. He then speculated that these will be similar to DMT plates but maybe slightly better because CBN should adhere to plates better than diamond.


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## M-S-T (Dec 7, 2020)

Well it all looks written up nicely but I really don't think it will be something exciting. Looks like a smart marketing move from spyderco. Cbn must be beter right? In most cases- yes. In that particular one- not really. Now let's look into the dry facts that we as sharpeners shouldn't even care about. Yes, cbn has a way higher hardness and thermal conductivity than alox or SiC, but diamond has a significantly higher hardness and thermal conductivity than cbn. If we would compare purest and strongest cbn and diamond grades. Diamond would be roughly 30% harder with almost double thermal conductivity. Cbn has higher thermal resistance tho. Again nothing that should really matter to us in this particular case. I really don't see any benefits of mono layer cbn over diamond. Technically, cbn should have a bit more predictable scratch pattern but It all depends on the general quality of the plate. My guess would be that you won't be able to tell the difference.


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## M-S-T (Dec 7, 2020)

Anyway, if the quality is good it looks like a good deal. If electroplated is your thing ofcourse.


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## kayman67 (Dec 7, 2020)

Testing from manufacturer in Germany proved that cbn layer is significantly more resilient. That's the point, nothing else. You won't tell the difference after the first usage (there wasn't one), but will matter after many sessions.


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## M-S-T (Dec 7, 2020)

Any knowledge on testing itself? Spherical wear resistance tesing with controlled presure and speed or something else?


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## kayman67 (Dec 7, 2020)

I imagine a manufacturer would consider things in all aspects. All kinds of microscope pictures were available and some data about how the layers behave with usage. 
It's very hard to near impossible to find stuff on Facebook even after just reading it.


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## Barmoley (Dec 7, 2020)

Like I've mentioned before, it should be similar to DMT plates but maybe slightly better because CBN should adhere to plates better than diamond. Spyderco usually has good QC/QA and quality products, so the hope is it will be done well. These will not replace vitrified or other types of synthetic stones in the feel or longevity department, but might be a good alternative to diamond plates.


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