# If I Drop A Solid VG10 Knife, Will It Shatter?



## manmachine (Sep 10, 2015)

First off, this forum is amazing! I've been finding amazing information in every thread. I really like the culture of this forum: these knives are tools, not decorations...and cheaper is better. Other knife forums are full of ill-informed collectors that don't use their knives, or really understand them, that buy $200 knives made of 440A. I myself have done my homework(and have the spreadsheets to prove it); however, I have a question about high-carbon stainless steel blades(VG10 and 'above'). Can they really absorb impact well enough to not shatter at, let's say, 240mm length? My fear is dropping a knife, or accidentally hitting something, and the knife snaps in two. Needless to say, this would pose a serious risk and I do not want microsurgery. Conventional wisdom in the other forums is that even these quality stainless steels can not be used for long blades because they are too brittle, especially at the HRC these knives are at.

So long story short, if I drop a 240mm solid VG10 gyuto at 59+ HRC from the counter onto the floor, how likely is it to snap in two? I imagine this to be the worst case scenario, but some of you guys may have seen accidents I can't imagine. To be clear, I am asking about a knife made of just VG-10(not clad with cheap stainless).


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## millionsknives (Apr 25, 2014)

More likely it will chip or break off the tip.  This can be repaired, but the profile may look different or you'll have to shorten the knife.  I haven't seen many just straight up snapped in half.


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## brianshaw (Dec 18, 2010)

From personal experience: drop tip-down onto ceramic tile floor from an altitude of 6 feet:

Tip bent - 5mm length at approx. 1-2mm deflection from straight.

Heel chip - 10cm length at 1mm depth.

Easily repaired and still in service.


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## rick alan (Nov 15, 2012)

Brian, who is even making a solid VG-10 knife???? No one. So of course your knives don't count here.

I dropped a Wusthof Ikon and Vic Rosewood on a tile floor from about 3 feet, jelly-side up fortunately, both landing on the spine. The Wusty, 59RC, showed micro-chipping along the entire edge from the shock alone. The Vic at about 55RC showed nothing for the insult. Is it any wonder then that the professional kitchen "house" knives are the typical NSF type coming in at <55RC?

The point of a Honyaki blade is to have a high-hardness monosteel, but with only the edge being fully hardened (typically 65-67RC). You'll see this being done with white and blue steels and some other carbons. I'm not sure this can be done with VG-10 because it is such a finicky thing to temper. Anyway the honyaki process makes them less prone to breakage, for such high edge hardness, but only in normal use. And they still do sometimes break in normal use.

There are a number of non-honyaki mono-steel knives out there that are around 60-61RC, and some PM steels much harder. But let's face it, good knives [in the sense being discussed here] are not made with the idea of surviving intact a significant fall onto anything, not even foam rubber.

Rick


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## brianshaw (Dec 18, 2010)

Oh. Ok Rick. Whatever you say. 

How does the info about you Vic and Wustie apply then??

At least my info had something to do with Vg10 blades, admittedly clad with "cheap stainless". But better that than just another flinging of cheap shots. Ha ha.

But your right that good knives not designed to sustain a fall, or other kinds of abuse.(edit: without some sort of damage, albeit not necessarily breaking or shattering)


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## manmachine (Sep 10, 2015)

Rick Alan said:


> Brian, who is even making a solid VG-10 knife???? No one. So of course your knives don't count here.


Actually they do exist. http://www.knifemerchant.com/products.asp?productLine=226 I've seen others as well that I will share soon. Of course, the product information can be wrong, which is why choosing a damned knife is so frustrating!


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## manmachine (Sep 10, 2015)

Honyaki, or differential hardening, is exclusive to carbon steels. Stainless steels can not be differentially hardened, even the high-carbon ones. That is why they use laminate steel: hardened steel and softer steel welded together. This mimics the effects of differential tempering, or honyaki or whatever version of the process. What I found bizarre is that I had assumed that laminate steels would use something like VG-10 for the blade and then a carbon steel for the rest of the knife, but in fact that is never the case(from what I've seen), and sometimes it's the other way around. I can not conceive of any advantage to a carbon blade clad with cheap stainless b/c you still need to maintain your blade and the cheap stainless can still corrode relatively easily. I also find it suspicious that only cheap stainless is ever used. Why not weld hard VG10 to soft VG10, or at least 440C, and get a superior knife?

Shun Classic Pro Series knives are solid VG10, as are others. I posted another post with a link, but it is awaiting moderation.


Rick Alan said:


> But let's face it, good knives [in the sense being discussed here] are not made with the idea of surviving intact a significant fall onto anything, not even foam rubber.


I find this ridiculous. Blades made of the proper high carbon tool steels using proper differential hardening will not break from minor impacts. At worst, the edge might get knicked. There are plenty of videos of swords/knives made of these steels and do not break even when used to break cinderblocks and bricks. Of course, if you're referring to classic Japanese carbon steels, then that may not be the case.


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## rick alan (Nov 15, 2012)

BrianShaw said:


> Oh. Ok Rick. Whatever you say.
> 
> How does the info about you Vic and Wustie apply then??


It applies as I am establishing how hardness affects toughness, it's very basic engineering principle and completely applies here. The accident resistance of your Shuns, being clad knives, simply doesn't apply to the OP which assumed such an advantage of cladding. On the other hand you could have stated that for the hell of it you were just giving a benchmark for cladded knives, instead of giving the appearance you didn't read the post carefully enough.


manmachine said:


> Honyaki, or differential hardening, is exclusive to carbon steels. Stainless steels can not be differentially hardened, even the high-carbon ones. That is why they use laminate steel: hardened steel and softer steel welded together. This mimics the effects of differential tempering, or honyaki or whatever version of the process. What I found bizarre is that I had assumed that laminate steels would use something like VG-10 for the blade and then a carbon steel for the rest of the knife, but in fact that is never the case(from what I've seen), and sometimes it's the other way around. I can not conceive of any advantage to a carbon blade clad with cheap stainless b/c you still need to maintain your blade and the cheap stainless can still corrode relatively easily. I also find it suspicious that only cheap stainless is ever used. Why not weld hard VG10 to soft VG10, or at least 440C, and get a superior knife?
> 
> Shun Classic Pro Series knives are solid VG10, as are others. I posted another post with a link, but it is awaiting moderation.
> 
> I find this ridiculous. Blades made of the proper high carbon tool steels using proper differential hardening will not break from minor impacts. At worst, the edge might get knicked. There are plenty of videos of swords/knives made of these steels and do not break even when used to break cinderblocks and bricks. Of course, if you're referring to classic Japanese carbon steels, then that may not be the case.


MM you are a bit all over the place here, but I'll answer some stuff.

Your speculations on why and how to use laminations show no understanding of the actual facts as I know them. The stainless used for the jigane is plenty non corrosive, cheap because it doesn't need to be anything else, and soft, like it's iron cladding counterpart, because that helps dampen shock to the cutting edge, which some people find especially attractive on certain knives.

Hitachi does make a san mai steel that has jigane that takes a temper, it is meant for field knives and at this time no one seems to see a need for it in kitchen knives, though it might be nice for something like a flexible fillet knife.

True layered steel knives, those containing no core steel, are typically made of a hardening and non hardening steel, and this allegedly adds to their toughness, but I've never seen any numbers, and this does not produce an edge as good as monosteel, at least no one has ever shown it to. Even Devin Thomas only speculates that some of his layered work with AEB-L may offer "certain" advantages over the monosteel.

I did a google search and in fact stainless is not so amenable to DHT, but there is at least one company claims the ability. I meant to correct myself there as it has been said that the Suisin Inox Honyaki is in fact not a real honyaki.

It would be difficult to weld a "hard" VG-10 edge to another piece of steel by any method I know of, though it is possible someone could come up with a process that protected the edge from the heat of welding with perhaps an induction heated silver solder or electron beam. Doing this with 2 pieces of VG-10 though is a bizzare consideration to me, given there is no advantage and VG-10 is expensive material. But then again the concept of your post seemed a little bizarre to me. After all who really cares about a monosteel VG-10 blade? Oh well, I answered to it anyway and, as you sort of state, Shun's marketing team seems to think there is a demand [that they can create].

Those demonstration swords you see smashing brick and cutting wire against iron plate are just that, demonstration swords. Swords in general are tempered soft in comparison to kitchen knives and also have much thicker edges, and the demo swords you speak of even more so, not to mention the spines, or things like soft core inserts behind the edge, rounding and softening of edge sections, etc. So, what is actually ridiculous is thinking a kitchen knife should perform this way, or even a proper sword. It will be a while for technology to bring us there.

Rick


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## brianshaw (Dec 18, 2010)

Oh. Ok Rick. Whatever you say. But at least the OP has some real data from a knife that has at least some VG10 major component. Might not be EXACT but it seems very odd that you feel empowered to declare it null and void. 

Adios.


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## brianshaw (Dec 18, 2010)

Please don't make things personal in public Rick. It's really bad form.


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## kuan (Jun 11, 2001)

Seriously people?


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## manmachine (Sep 10, 2015)

I will try to keep this as civil as possible. Rick Alan, it is people like you I was trying to avoid by coming to this forum instead of the knife collectors forums. You have been wrong on almost every point you've made and demonstrated serious fundamental gaps in your knowledge. It is clear that you don't know what tempering is, and please, for the love of all that is good, look up the term "forge welding." If you want to learn, I'd be happy to explain some things to you through pm, but will not do so on this thread in order to keep it on track. I suggest reading through the info on the zknives website for an introduction. It is not perfect, but it is far better than learning from a bunch of newbies pretending to be experts on the knife collecting forums(which seems to be what you did). I will no longer address your comments in this thread.

So back to the original thread. German knives, like Wusthof, are made from solid stainless similar to VG10, but with much lower carbon content. They are hardened to a low HRC(54 - 56) though and they withstand impacts very well. Will 240mm knives made of high carbon stainless steels(I hate the confusing terminology) such as VG10 and S30V be able to retain the shock resistance at high HRC(59+) that knives made of X50CrMoV15(Wusthof) have at lower HRC? If not, I see no reason to choose any knife steel other than solid PM high carbon tool steels, in particular if they have some chromium added for moderate corrosion resistance.


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## phaedrus (Dec 23, 2004)

You won't shatter any steel knife with a normal drop.  You might chip the edge or break off the point.  I have fixed many broken tips and chipped edges.  The knife will be different but still serviceable.


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## manmachine (Sep 10, 2015)

Benuser said:


> Just surprised by the said similarity between Wüsthof's stuff and VG-10. No, these are very different steels. The Germans choose long time ago an almost undestructable, tough steel, while much more recently, when VG-10 was developed, carbon-like performance was the aim.


http://zknives.com/knives/steels/steelgraph.php?nm=X50CrMoV15,VG10&hrn=1&gm=0 If you look here, you will indeed see that in fact they are quite similar steels. The most significant difference is the carbon content, which is specifically what I mentioned. I don't like to go by these charts, but by real world use, which is why I'm asking 

Btw, I did no ad hominem attacks because I wasn't arguing. Thanks for being the first to actually answer the question though. I will take a long look at the JCK Kagayaki series. You've been a great help.


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## manmachine (Sep 10, 2015)

Phaedrus said:


> You won't shatter any steel knife with a normal drop. You might chip the edge or break off the point. I have fixed many broken tips and chipped edges. The knife will be different but still serviceable.


I personally have seen stainless steel knives break in two from gentle drops from a counter. If you'd like, I can post a picture of a personal knife that broke that way. The knives I have seen that happen to were cheap though, but they are why I have the concern. I trust that you are right though; any quality knife should be fine. I just don't want to mistakenly buy one that is more for decoration and holiday gifting than actual use. Thank you for the response.


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## phaedrus (Dec 23, 2004)

manmachine said:


> I personally have seen stainless steel knives break in two from gentle drops from a counter. If you'd like, I can post a picture of a personal knife that broke that way. The knives I have seen that happen to were cheap though, but they are why I have the concern. I trust that you are right though; any quality knife should be fine. I just don't want to mistakenly buy one that is more for decoration and holiday gifting than actual use. Thank you for the response.


That is certainly not normal! Almost certainly the knife had a flaw in the manufacture or was previously stressed. I cannot count how many knives I've seen hit the floor in nearly 30 years in restaurant kitchens but I have yet to see one break in half.

Still, one should be careful. It's easy to break a tip or chip and edge.


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## manmachine (Sep 10, 2015)

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manmachine


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Here is a personal knife that broke in two from a gentle drop onto tile floor. It landed on its spine iirc as knives tend to do. Every stainless steel will break this way if excessively hardened or if excessively long. Obviously this is a cheap knife, but despite a short 4.5" blade, still shattered because of the high HRC(this knife takes an edge fairly well, you just have to hone before every meal.). I know quality steels will withstand more punishment, even at high HRC; I was just wondering if VG10 was amongst them. From the responses in this thread, it seems that VG10 is a safe choice, but I think I still prefer PM tool steel.


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## brianshaw (Dec 18, 2010)

Thanks for posting the picture. That is very interesting. I never doubted you but I have never seen such an event (or known anyone else who has). 

Only once have I broken a knife but it was a really cheap Ikea utility knife and I was using it to cut dandelion roots... and definitely torqued it right before the blade snapped. Mine snapped at the handle, though, and not in the middle of the blade. But a Rick would say, that story has nothing to do with good knives.


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