Massdrop- Diamond Stones

[HumbleHomeCook]

Whoa, not agreeing with @Deadboxhero is one thing but calling him out because he sells stones is not cool at all.

Shawn Houston is one of the most giving people in the knife world with a massive amount of knowledge that he not only readily shares, but spends a lot of money on helping research and develop. He's inspired countless sharpeners, enthusiasts, and even fellow knife makers. And that includes in the kitchen knife world.

You can not like his style if you want, that's cool, and you can debate his positions, but he doesn't do anything from a salesman point of view and ALWAYS has the user in mind! He only sells stones because he couldn't find anything out there to accomplish what he wanted to accomplish. But he readily promotes other people's products and other sharpener's work.

He's a damn solid person with a heavily established reputation.

 

[Kippington]

You guys are totally off base questioning Shawn‘s integrity just because he happens to sell diamond stones. He has very extensive experience in sharpening and working with all sorts of high wear, high hardness, high carbide steels and he uses what works for him. He’s worked with materials that very few here if any have worked with. You might disagree with his conclusions or reasons, but to assume that he would promote diamonds just because he sells them is absolutely uncalled for and just isn’t cool at all.

I don't doubt.
I'm pretty sure none us on the forum have a problem with diamond abrasives. But I'm not a fan of strawman style arguments.

You're making it sound like softer abrasives don't have consequences as well, The problem with soft abrasives...

 

[Barmoley]

His most recent article? My take-away was that diamonds tend to crack carbides, moreso than other abrasives which left carbides standing proud. Interesting you saw it a different way.

www.scienceofsharp.com

Didn’t he also say that the cracked carbides were on the part of the burr that flexed the most? He also used diamond plates, so we still don’t know if the cracks are specifically due to diamonds, a possibility, or specifically how diamonds are on a plate. Can we really draw conclusions from this that diamonds in other types of diamond stones would produce the same results? Cool article though.

 

[kayman67]

His most recent article? My take-away was that diamonds tend to crack carbides, moreso than other abrasives which left carbides standing proud. Interesting you saw it a different way.

www.scienceofsharp.com

Not only me.
"Close-up of the K390 Endela sharpened on the Sigma Power II 240 shows partially abraded carbides at the surface with severe cracking."

Also, worth mentioning is this "Close-up of the cross-sectioned burr formed by the DMT-C shows damaged carbides in the most flexed region." + "Close-up of a carbide near the surface that has been partially ground showing severe cracking."

So, there are some mixed results right there. Not my words, either.

I don't question some things. I just have my own real life experience, my own progression and so on. Pretty hard to change all those now, since they are also actual facts.

 

[Kippington]

Not only me.
"Close-up of the K390 Endela sharpened on the Sigma Power II 240 shows partially abraded carbides at the surface with severe cracking."

Also, worth mentioning is this "Close-up of the cross-sectioned burr formed by the DMT-C shows damaged carbides in the most flexed region." + "Close-up of a carbide near the surface that has been partially ground showing severe cracking."

That's true, I wonder what the abrasive is in the Sigma.
It seems that anything much harder than carbides tend to cause micro-cracking within the carbide itself.

Didn’t he also say that the cracked carbides were on the part of the burr that flexed the most?

There were a couple of other pictures further away from the burr. But yeah, the burr seems to compound the issue.

 

[kayman67]

Based on the conclusion, that's pretty much how the carbides got removed with all the abrasives, diamonds being just faster and more aggressive, as expected, doing both jobs at once. He does say at some point that changing the angles to reduce flexing to minimal with Shapton, also reduced the damage. This makes me wonder just how much is the abrasive and how much the way it is used in specific scenarios. Because plates are aggressive in nature, have no give whatsoever. I know it myself.

 

[Dominick Maone]

You guys are totally off base questioning Shawn‘s integrity just because he happens to sell diamond stones. He has very extensive experience in sharpening and working with all sorts of high wear, high hardness, high carbide steels and he uses what works for him. He’s worked with materials that very few here if any have worked with. You might disagree with his conclusions or reasons, but to assume that he would promote diamonds just because he sells them is absolutely uncalled for and just isn’t cool at all.

Agreed. I believe Shawn is somewhat of an authority on high hrc and carbide rich knife steels and ways to best sharpen them. He was the (or one of the) sharpeners for Dr Larrins Catra test on 48 knife steels. I think it is naive to assume that Sean is saying you can take a kitchen knife off the rack and hammer it through a nail.

Anyway, I guess my hope of a mass drop is over. Too bad when someone asks the best way to buy a Chevy, everyone has to mention how crappy Chevys are.

Maybe we should close this thread and someone can start a new thread about the benefits and drawbacks of abrasive types.

 

[Deadboxhero]

With this thread title in mind, I wondered why you wanted me to concentrate on the negatives of other abrasives so much... then I realised you must be the guy selling the diamond stones. Makes sense now.
I don't have a horse in this race.

If the gentleman in the video addresses microcracking in a 0.34% w C steel, no offence but I'm trusting his word over yours. He ain't exactly the kind of guy whose concerns you dismiss, on the subject of metallurgy.

https://en.wikipedia.org/wiki/Harshad_Bhadeshia

You're misunderstanding and misquoting Professor Bhadeshia.

You posted an hour+ long video and are using it out of context. He doesn't start talking about lower carbon martensite until 10:07 and than he doesn't discuss the 0.34%wt C steel until 14:16 which is designed to fully harden during hot rolling.

You time stamped the video at 4:03

Here Professor Bhadeshia is discussing cracking due to plate martensite in high carbon steels and is referencing an article he did on 52100 to study cracking with purposly putting too much carbon in solution making plate martensite to study crack behavior of large plates of martensite.


Solano, Bhadeshia.Metall.Mater. Trans A. 49A (2014) 4907

"Crack free" at 1133k (1579°F) FOR 10 MIN.

So I agree with Professor Bhadeshia.


You also used this picture out of context.

The original picture comes from A.R Marder 1970. To study cracking by taking high carbon steels and putting too much carbon in solution to observe/study the cracking phenomena of plate martensite. Not "0.34% wt Carbon steel" or 0.34% wt Carbon in solution.

 

[Kippington]

You're misunderstanding and misquoting Professor Bhadeshia.

You posted an hour+ long video and are using it out of context. He doesn't start talking about lower carbon martensite until 10:07 and than he doesn't discuss the 0.34%wt C steel until 14:16 which is designed to fully harden during hot rolling.

You time stamped the video at 4:03

View attachment 142759

Here Professor Bhadeshia is discussing cracking due to plate martensite in high carbon steels and is referencing an article he did on 52100 to study cracking with purposly putting too much carbon in solution making plate martensite to study crack behavior of large plates of martensite.


Solano, Bhadeshia.Metall.Mater. Trans A. 49A (2014) 4907

View attachment 142758

View attachment 142762

"Crack free" at 1133k (1579°F) FOR 10 MIN.

So I agree with Professor Bhadeshia.


You also used this picture out of context.

View attachment 142764


The original picture comes from A.J Marder 1970. To study cracking by taking high carbon steels and putting too much carbon in solution to observe/study the cracking phenomena of plate martensite. Not "0.34% wt Carbon steel" or 0.34% wt Carbon in solution.

So you're saying he brought up micro-cracking for no reason - out of context - in a lecture about the considerations in developing a new medium carbon steel alloy? Alright then.
As much as we could go down this road, we should probably stay on topic.
https://www.kitchenknifeforums.com/threads/massdrop-diamond-stones.55108/

 

[M1k3]

That's true, I wonder what the abrasive is in the Sigma.

The 240 is SiC

 

[Deadboxhero]

So you're saying he brought up micro-cracking for no reason - out of context - in a lecture about the considerations in developing a new medium carbon steel alloy? Alright then.
As much as we could go down this road, we should probably stay on topic.
https://www.kitchenknifeforums.com/threads/massdrop-diamond-stones.55108/

Professor Bhadeshia is setting the discussion up for the "how and why" his 0.34%w C steel he designed works in the as quenched condition after being hot rolled has 0.34%wt Carbon and not 1.05% C etc like 52100

We can start another thread if you like.
I didn't post that video here to begin with. However, feel obligated to share if misinformation/misunderstanding is being presented.

That is the spirit of the forums after all, to discuss details and conflicting views.

 

[jedy617]

So is there a group buy going on or nah? If so tag me when it's going down

 

[Kippington]

We can start another thread if you like.

You can start one. I've heard enough.

 

[jedy617]

You can start one. I've heard enough.

I'm good. Someone just lemme know when it's time

 

[HumbleHomeCook]

You can start one. I've heard enough.

Me too.

 

[Luftmensch]

Back on track... I am interested in a group buy....

Certainly something like this could be managed, but what would be the unique attraction to a massdropped stone vs. folks going and buying one at their preferred grit?

I've considered stones previously so happy to discuss the topic.

Good question.

Bulk discount? Fancy KKF/BBB stylized branding?

I would be interested for the potential of a bulk discount and accessibility. Interesting stones are not rare as hens teeth... but they are often expensive and sold out. A group buy may streamline that process for some.



Do we have somebody fluent in Japanese? Like I said earlier, I have a hunch that NSK might do a small batch order - they already do made-to-order products (I dont know what volume). Could choose from:

• Sintered diamond (new)
• CBN
• Sintered diamond (old)

They might be willing to do custom thicknesses, colours... etc. I am not claiming NSK are better than alternatives. I simply dont know... Again, like I said... I suspect they are the supplier for other brands sold in the 'West'. So I don't think they are complete wildcard.

If there is interest, it would be good if a Japanese speaking forum member could see if they are willing to work with us. It would be even better if we could properly understand the differences between their old and new diamond stones - google translate doesnt do a great job.



.... anyway... just a starting point for getting the thread back on track

 

[M1k3]

Back on track... I am interested in a group buy....



Good question.



I would be interested for the potential of a bulk discount and accessibility. Interesting stones are not rare as hens teeth... but they are often expensive and sold out. A group buy may streamline that process for some.



Do we have somebody fluent in Japanese? Like I said earlier, I have a hunch that NSK might do a small batch order - they already do made-to-order products (I dont know what volume). Could choose from:

• Sintered diamond (new)
• CBN
• Sintered diamond (old)

They might be willing to do custom thicknesses, colours... etc. I am not claiming NSK are better than alternatives. I simply dont know... Again, like I said... I suspect they are the supplier for other brands sold in the 'West'. So I don't think they are complete wildcard.

If there is interest, it would be good if a Japanese speaking forum member could see if they are willing to work with us. It would be even better if we could properly understand the differences between their old and new diamond stones - google translate doesnt do a great job.



.... anyway... just a starting point for getting the thread back on track

Maybe @Dave Martell has some experience with NSK?
https://www.kitchenknifeforums.com/threads/naniwa-diamond-stones.37181/post-556602

 

[Luftmensch]

Maybe @Dave Martell has some experience with NSK?
https://www.kitchenknifeforums.com/threads/naniwa-diamond-stones.37181/post-556602

I would definitely be keen to hear! @Dave Martell ?

Like I say, I am pretty sure NSK are familiar to the community under different branding. I'll stop there. I don't want to 'out' any vendors based on speculation



(Personally I am not too bothered about supersteels or minutiae about what happens to the edge at a micro-level. A high performing and nice feeling low & mid grit stone that dishes slowly interests me a lot... I am very close to ordering a Venev combination stone. If we can do something fun on KKF, I might hold off on that!)

 

[captaincaed]

I'd be interested in a bulk order because I'm interested in having three vitrified stones at the same grit level so they can be used to flatten one another. Every stone eventually needs it.

I'm also interested in flatness, especially for chisels. Diamond plates are the old standby for wood tools, but these would do better double duty with knives, so I wouldn't need two sets. I guess I'd need three sets with the logic I just laid out. Wait a minute...

 

[Luftmensch]

I'm also interested in flatness, especially for chisels. Diamond plates are the old standby for wood tools, but these would do better double duty with knives, so I wouldn't need two sets.

In the long run I would love to do more woodwork. I saw your progress on the cutting boards .

I am very much onboard with your thinking! For the little wood projects I do, I have a decent set of chisels and some smaller planes. I dont have any powered methods for sharpening them. This is 70% of the reason I am keen on low and mid grit stones that maintain flatness. The other 29% might be knife thinning.

Regular high grit stones wear slowly enough not to be a pain.

 

[captaincaed]

Indeed ( and thank you)! Looking for that low grit magic. I am so sick of my 220 pink brick.

 

[inferno]

if you need flatness, the plates aren't too bad if you are willing to follow up with a real stone to erase the scratches. i regard the plates as consumables. plates are very fast (when new at least). and regular stones are very fast too. to me speed is important.

 

[inferno]

I'd be interested in a bulk order because I'm interested in having three vitrified stones at the same grit level so they can be used to flatten one another. Every stone eventually needs it.

I'm also interested in flatness, especially for chisels. Diamond plates are the old standby for wood tools, but these would do better double duty with knives, so I wouldn't need two sets. I guess I'd need three sets with the logic I just laid out. Wait a minute...

this is exactly what you should do. get 3 sets of 3 different stones!! like a boss.

 

[inferno]

btw is there a reason there are no/very few cbn stones?

there is also another abrasive called boron carbide Boron carbide - Wikipedia
this one seems to be much cheaper than cbn since you can actually but solid stones made out of it. they are used to condition grinding wheels.
looks like this one below but carbide. size small but its still a solid chunk. and these are expensive.

https://www.nortonabrasives.com/en-us/product/norbide-boron-nitride-type-54-dressing-stickhttps://www.nortonabrasives.com/en-us/product/norbide-norbide-boron-carbide-type-54-dressing-stick

 

[captaincaed]

this is exactly what you should do. get 3 sets of 3 different stones!! like a boss.

I swear if the price is right in feeling that crazy

 

[inferno]

i dont think any vitrified stones ever gonna be cheap. its a too specialized product.

 

[M1k3]

btw is there a reason there are no/very few cbn stones?

there is also another abrasive called boron carbide Boron carbide - Wikipedia
this one seems to be much cheaper than cbn since you can actually but solid stones made out of it. they are used to condition grinding wheels.
looks like this one below but carbide. size small but its still a solid chunk. and these are expensive.

https://www.nortonabrasives.com/en-us/product/norbide-boron-nitride-type-54-dressing-stickhttps://www.nortonabrasives.com/en-us/product/norbide-norbide-boron-carbide-type-54-dressing-stick

I think @ian tried some boride?

 

[ian]

I think @ian tried some boride?

Only internally.

 

[memorael]

I'd like to see a link to that study.

Tried searching for it on sharprazorplace and badger and blade but couldn't find it. I'll keep looking, if I find it I'll post it.

 

[Barmoley]

btw is there a reason there are no/very few cbn stones?

I've read somewhere that it is due to price. This surprised me greatly since I thought diamonds would be more expensive, but on commercial level maybe this is not the case due to synthetic diamonds. CBN is used a lot in high speed grinding since diamonds have issues with high temperatures and some metals at high temperatures.