# CPM M4 for a kitchen knife



## Barmoley (Aug 1, 2017)

I know steel is just one of many parts of a good kitchen knife, but what does the collective think of CPM M4. It seems to do really well in all sorts of cutting competitions. It is pretty tough even at high hardness levels, has relatively small grain size for an alloyed tool steel, and should be able to support thin edges. It is wear resistant and can be used at 64 HRC without being brittle. It is not stainless, but more so than 52100 and other usual carbons. Anyway, sounds like it should work....


----------



## Matus (Aug 1, 2017)

I think that it will be tough to sharpen, otherwise I see no reason why it should not perform well.


----------



## Barmoley (Aug 1, 2017)

Could be. But if the edge is held very thin, if the steel can support it, then it shouldn't be that bad. Especially using diamonds....


----------



## J_Style (Aug 1, 2017)

I had a Nora in M4. 67.5 rc. I sharpened it once on my JKI 800 diamond then 5k shapton pro. Didn't seem harder to sharpen.


----------



## Matus (Aug 1, 2017)

Barmoley said:


> Could be. But if the edge is held very thin, if the steel can support it, then it shouldn't be that bad. Especially using diamonds....



Yes, and that (the diamonds) is the reason why this steels are often used on pocket and outdoor knives - most users of which use some kind of sharpening device that gives them sharp edges in no time (I have one too - forgot the name). Those users do not need to thin their knives (mostly because they use them rather little) all that often (read - not at all).

Still - I am not saying that CPM M4 would be too tough to sharpen - one of the reasons we do not see it much around here is lack of the suitable stock material + price. I was actually looking for CPM D2 and failed to find some.


----------



## milkbaby (Aug 1, 2017)

I agree with Matus, but only as a matter of looking at the composition versus actual personal experience using the steel. One of the great things about relatively simple carbon steel is how sharp it gets and how easily that super sharp edge is maintained. I'm guessing the higher alloying in M4 gives better wear resistance due to the carbides formed, especially the tough tungsten and vanadium carbides. But then you probably give up some of the easy sharpening you'd have in a low alloy simpler carbon steel.

Is there somebody out there making kitchen knives regularly from CPM M4? Or are you deciding on a custom?


----------



## Barmoley (Aug 1, 2017)

I don't know if anyone is making CPM-M4 steel kitchen knives regularly. My question is academic, I just noticed that it is used a lot for many years now for cutting competitions. Lately, like Matus said it's been used a lot in pocket knives by Spyderco and Benchmade as well as some others. CPM process supposedly allows carbides to be smaller and well distributed, so this might help some in sharpening department.


----------



## Barmoley (Aug 1, 2017)

I think Matus is right. The problem is thinning , sharpening would be ok but once you had to thin......

It would probably work well as core steel or for petties, sujis, etc, not so much for gyutos.


----------



## malexthekid (Aug 1, 2017)

I think the guy from Houston Edge Works, or whatever its name, is uses it. I also think butch harner may have experience with it if my memory about steel discussions is correct


----------



## Ruso (Aug 1, 2017)

It should be a decent steel for KF, but it's a tough steel, kinda of an overkill for this purpose. But I would consider getting one from a good maker (read HT).


----------



## J_Style (Aug 1, 2017)

Nora Knives makes quite a few using m4, there's a few other makers using it also. It would be tough to thin, maybe best on pettys or thin slicers.


----------



## Barmoley (Aug 2, 2017)

These actually look pretty good from the pictures. Has anyone ever used any of them? How are the grinds? I still think that it would be too difficult to deal with when thinning, but a petty or smaller utility knife could maybe work well.


----------



## loong (Aug 3, 2017)

Personally I think ZDP-189 steel is pretty close to M4 steel. You may get lots of choice from the former material.


----------



## Eloh (Aug 3, 2017)

It's more similar to Hap40 actually...
And you can find quite decent Laser-ish Gyutos with this steel, too:
http://kochmalscharf.freeforums.net/thread/1308/kohsey-hap40-tsuchime-gyuto-270mm

the review is actually pretty positive, too. Edge retention is outstanding, as expected, Sharpenability is ok, if you know what you're doing.


----------



## Barmoley (Aug 3, 2017)

Yeah, Hap40 is the closest of the "usual" suspects, even though it is still pretty different, but should act in similar matter given optimal heat treat for each.


----------



## kurwamac (Aug 4, 2017)

Does anyone know of any EU makers selling knives in this stuff as of the moment? Or yanks that will ship to the UK?


----------



## parbaked (Aug 4, 2017)

kurwamac said:


> Does anyone know of any EU makers selling knives in this stuff as of the moment? Or yanks that will ship to the UK?



Get in touch with Nora Knives. They uses mostly AEB-L and M4. This page describes their experience with these two steels. 
There's a comparison chart at bottom of page.
https://noraknives.com/pages/steel-options


----------



## Matus (Aug 4, 2017)

One thing needs to be said - it would appear that CMP/PM steels are easier to grind than non-CPM steels. I have made a little knife from Damasteel (mix of two PM steels) and it was sooo easy to grind and to sand - bordering enjoyable  So the CPM M4 does not have to be so bad to sharpen after all. I would say this needs to be tested


----------



## Barmoley (Aug 4, 2017)

Hmm... I think we need to get Matus some CPM M4 to play with :rofl2:


----------



## Matus (Aug 4, 2017)

Barmoley said:


> Hmm... I think we need to get Matus some CPM M4 to play with :rofl2:



I am in


----------



## valgard (Aug 4, 2017)

Barmoley said:


> Hmm... I think we need to get Matus some CPM M4 to play with :rofl2:



+1


----------



## comet_sharp (Aug 4, 2017)

I can get M4 readily available in many sizes. Send me a message on IG Matus if you want me to get ya some.


----------



## Matus (Aug 5, 2017)

comet_sharp said:


> I can get M4 readily available in many sizes. Send me a message on IG Matus if you want me to get ya some.



You will be hearing from me soon


----------



## Ruso (Aug 5, 2017)

Matus said:


> You will be hearing from me soon



When is the passaround of Das Matus Messer?


----------



## Matus (Aug 5, 2017)

Well, it may take a while, but why not? Steel has already been located thanks to comet_sharp, but I expect it to reach me only in a few weeks and the I will work on the knife next to other projects.

Realistic start of the passaround would be end of the year. No need to sign up for it yet


----------



## natto (Aug 6, 2017)

Hi Matus, now this thread becomes interesting. I read it out of curiosity, nearly 20 percent of carbide builders don't fit thin edges to me. Do you have a HT in mind already?

edit: http://www.4steel.nl/img/CPMRexM4.pdf
a datasheet in German language


----------



## Matus (Aug 6, 2017)

Natto, I will discuss the HT with Jürgen Schanz as he does all stainless and semi stainless HT for me.
Edit: thanks for the data. This steel is not going to be easy to HT I guesd


----------



## natto (Aug 6, 2017)

It would be great if you could put some light on this high alloyed pm steels, pros and cons and how to heat treat. In my head this is in a pretty dark corner. Thank you.


----------



## Matus (Aug 6, 2017)

Natto, I can ask Jürgen how he will HT it (if he will be willing to share that)


----------



## natto (Aug 6, 2017)

Take your time, I'll stay curious.


----------



## scott.livesey (Aug 8, 2017)

Matus said:


> I am in



Alpha Knife Supply carries CPM M4 https://www.alphaknifesupply.com/shop/product/m4-carbon-steel. you will find the shipping is as much as the steel, the issue I face buying 1.2519 or 1.2842 from Germany. M4 and other HSS steels are very high in carbides which give good edge retention but poor toughness, especially when used in a high performance slicer where you are 0.005"(0.125mm) or less at the edge, 0.020" 1/4" above, 0.025" 1/2" above.


----------



## scott.livesey (Aug 8, 2017)

Matus said:


> Natto, I will discuss the HT with Jürgen Schanz as he does all stainless and semi stainless HT for me.
> Edit: thanks for the data. This steel is not going to be easy to HT I guesd



the steel requires very high heat, 1200C for HT. Vacuum or controlled atmosphere furnace recommended, not quite what I have in my shop.


----------



## Larrin (Aug 9, 2017)

scott.livesey said:


> Alpha Knife Supply carries CPM M4 https://www.alphaknifesupply.com/shop/product/m4-carbon-steel. you will find the shipping is as much as the steel, the issue I face buying 1.2519 or 1.2842 from Germany. M4 and other HSS steels are very high in carbides which give good edge retention but poor toughness, especially when used in a high performance slicer where you are 0.005"(0.125mm) or less at the edge, 0.020" 1/4" above, 0.025" 1/2" above.


The toughness of steels like Cowry-X and ZDP-189 is much, much lower than CPM-M4.


----------



## pennman (Nov 4, 2018)

Barmoley said:


> I know steel is just one of many parts of a good kitchen knife, but what does the collective think of CPM M4. It seems to do really well in all sorts of cutting competitions. It is pretty tough even at high hardness levels, has relatively small grain size for an alloyed tool steel, and should be able to support thin edges. It is wear resistant and can be used at 64 HRC without being brittle. It is not stainless, but more so than 52100 and other usual carbons. Anyway, sounds like it should work....





malexthekid said:


> I think the guy from Houston Edge Works, or whatever its name, is uses it. I also think butch harner may have experience with it if my memory about steel discussions is correct



M4 is an awesome steel for her knives. I have been using it for years. All my chefs and customers who have it, love it. It has a unique “feel” when cutting. Performance outstrips ZDP-189 noticibly which is more like Elmax.


----------



## rick alen (Nov 4, 2018)

Just listening to the comments of users in this forum it seems that HAP40 is more in the category of R2 and SRS-15, which in terms of carbide content are no where near ZDP if the 36% carbide content I've heard claim is for real. I had thought M4 was closer to S110V there. Alpha supply carries CPM M4, no mention of it being out of stock:
https://www.alphaknifesupply.com/shop/cpm-m4-carbon-steel

There is a test on utube comparing a number of steels used in knives from various makers. A Spiderco in S110V was compared to one made and HT'd by Phil Wilson. Wilson's knife was said to have shown twice the wear resistance of the Spiderco version, and was the clear winner of the edge retention contest. I know these utube comparisons can be quite ridiculous, but the guy doing this one seemed truly impartial and legit. Anyway HT does seem obviously much more critical with the higher alloy PM's.

Phil takes his S110V knives to a .010"/.25mm edge, says they should have a minimum 30def inclusive edge, though I suppose this could be a micro-bevel. I know R2 needs a good microbevel if you're going to hit the board with it, less so for SRS-15 (which I absolutely love) it seems to me, I'd guess M4 is pretty good here though probably still not supporting too steep an edge.


----------



## Barmoley (Nov 4, 2018)

CPM M4 is supposed to be much tougher than any of the aforementioned steels. It is used in competition choppers in blade sports. Of course geometry there is totally different than a chef knife would have, but that's an indication of what the steel can do, since these guys can use any steel they want. Lately they've been switching to 4v but m4 is still used a lot.

The largest knife in m4 I have is a 150mm petty which is very thin it is heat treated to 64 HRC, the edge is very acute and the retention is very good, possibly better than even hap40, not sure yet. The problem is that a petty is not used in the same way as a larger knife so hard to tell.

Really the only negative a chef knife in CPM m4 would have would be sharpening and even more so thinning if it was a mono steel blade. That would surely be a chore. Now, if someone made a clad knife with m4 core that would be very interesting. Of course I would love to try a mono in m4 as well. They are expensive though, for a good reason I am sure since steel is difficult to deal with.


----------



## pennman (Nov 5, 2018)

Barmoley said:


> CPM M4 is supposed to be much tougher than any of the aforementioned steels. It is used in competition choppers in blade sports. Of course geometry there is totally different than a chef knife would have, but that's an indication of what the steel can do, since these guys can use any steel they want. Lately they've been switching to 4v but m4 is still used a lot.
> 
> The largest knife in m4 I have is a 150mm petty which is very thin it is heat treated to 64 HRC, the edge is very acute and the retention is very good, possibly better than even hap40, not sure yet. The problem is that a petty is not used in the same way as a larger knife so hard to tell.
> 
> Really the only negative a chef knife in CPM m4 would have would be sharpening and even more so thinning if it was a mono steel blade. That would surely be a chore. Now, if someone made a clad knife with m4 core that would be very interesting. Of course I would love to try a mono in m4 as well. They are expensive though, for a good reason I am sure since steel is difficult to deal with.



M4 can’t be clad. It’s a rediculiusnsteel to weld. M2 can be clad. Excellent performance, but not M4. Hardened M4 cannot be thinned by hand. It actually can not be ground with anything higher than a 120 grit ceramic belt. These are both M4 blades.


----------



## Barmoley (Nov 5, 2018)

These look nice. What are some specs on them? Are they on your website?

Interesting info about M4, I suspected that it might cause some problems, it is surprising that it acts so different from HAP 40.


----------



## pennman (Nov 5, 2018)

Barmoley said:


> These look nice. What are some specs on them? Are they on your website?
> 
> Interesting info about M4, I suspected that it might cause some problems, it is surprising that it acts so different from HAP 40.




No. Not on website. These were two of the three I made for Andrew Zimmern. They are 255mm long. The chef is 63mm at heel. The slicer is about 47mm at the heel. The balance is 1cm in front of the choil. They are hellacious cutters and cut as easily as a ghost walks through walls.


----------



## samuraistuart (Nov 6, 2018)

I have made a few kitchen utility knives in CPM M4. Great steel, edge retention is just awesome. The knife above is my personal utility knife, CPM M4 with the modified Δ heat treat, so it has more free chromium. I use it exclusively for protein cutting, and after 2 years of light use, it has yet to even begin to hint at patina formation. The edge has never been touched up or re-sharpened. Same edge it had when new 2 years ago, and will easily shave arm hair today. I don't abuse it, it rarely makes hard contact on the wooden cutting board, and it gets babied. The only complaint I have against CPM M4....hand sanding the blade. It simply laughs at sandpaper. A total pain in the rear to get a nice satin hand rubbed blade finish. But worth it in the end! 1.8mm/0.070" at the spine, 0.13mm/~0.005" prior to sharpening, full flat grind, 15° per side, DMT EEF 3 micron makes for a wicked cutting edge on CPM M4.


----------



## Barmoley (Nov 6, 2018)

The 150 mm CPM-M4 petty I have is one of yours. The edge retention is great, would love to try CPM-M4 in a chef knife, ofcourse geometry would have to be different, as flat grind in a chef size knife would be very sticky. I wonder how the edge retention would be with a lot of board contact as chef knives experience. In theory should still be great as the steel has pretty good combination of wear resistance and toughness.


----------



## samuraistuart (Nov 8, 2018)

Chef's knives really should have a sort of convex to them at least on one side to help with food release. It doesn't need to be pronounced, just slight. I agree, even with moderate or heavy board contact, CPM M4 will have better edge retention than many steels. It has a few things going for it, not the least of which is high attainable working hardness. 64HRC is not found often, except maybe in White or Blue steel Japanese knives. I believe hardness is the greatest contributor to overall edge retention in a knife, especially a kitchen knife. Then it needs to be tough enough to be used at that hardness, of which CPM M4 has that in spades. Wear resistance really has limited use in most knife cutting applications. Especially a kitchen knife. Food just isn't that abrasive, otherwise our teeth would be nubs. It would be interesting to do a side by side comparison of identical knives, 64HRC M4 vs 64HRC White steel, in the kitchen (only the kitchen, both knives doing exactly the same work). I think the end result would surprise a lot of people, in the same way AEB-L has surprised a lot of people with it's performance and such a simple chemistry.


----------



## Matus (Nov 9, 2018)

How does CPM M4 at this high hardness behave on sharpening stones? Or is it a ‘diamond only’ steel?


----------



## chefcomesback (Nov 9, 2018)

M4 can be clad , I have a friend that does it regularly . He says welds super easy ,
When asking for experiences of steels you guys may want to ask people who actually have an actual experience of heat treating and testing them in person


----------



## Barmoley (Nov 9, 2018)

Would love to. Unfortunately I couldn't find anybody who would make one for me or even tell me that it's possible.


----------



## captaincaed (Nov 9, 2018)

samuraistuart said:


> I have made a few kitchen utility knives in CPM M4. Great steel, edge retention is just awesome. The knife above is my personal utility knife, CPM M4 with the modified Δ heat treat, so it has more free chromium. I use it exclusively for protein cutting, and after 2 years of light use, it has yet to even begin to hint at patina formation. The edge has never been touched up or re-sharpened. Same edge it had when new 2 years ago, and will easily shave arm hair today. I don't abuse it, it rarely makes hard contact on the wooden cutting board, and it gets babied. The only complaint I have against CPM M4....hand sanding the blade. It simply laughs at sandpaper. A total pain in the rear to get a nice satin hand rubbed blade finish. But worth it in the end! 1.8mm/0.070" at the spine, 0.13mm/~0.005" prior to sharpening, full flat grind, 15° per side, DMT EEF 3 micron makes for a wicked cutting edge on CPM M4.



Is this something you still do / do publicly?


----------



## pennman (Nov 10, 2018)

chefcomesback said:


> M4 can be clad , I have a friend that does it regularly . He says welds super easy ,
> When asking for experiences of steels you guys may want to ask people who actually have an actual experience of heat treating and testing them in person



Who is it that clads M4 successfully? Greg Cimms has been trying to clad M4 for me and himself. It basically explodes. But I’m sure he is too inexperienced in heat treating and testing them in person.


----------



## chefcomesback (Nov 10, 2018)

Before you clutter this forum or any other other social media with your bs I want to ask you ,
Have you ever heat treated a knife ?
Have you ever forge welded or made san mai ?
It will be nice to know these answers before you spread ed any of your “wisdom”


----------



## pennman (Nov 10, 2018)

chefcomesback said:


> Before you clutter this forum or any other other social media with your bs I want to ask you ,
> Have you ever heat treated a knife ?
> Have you ever forge welded or made san mai ?
> It will be nice to know these answers before you spread ed any of your “wisdom”


Yes, I have heat treated knife steel. But I don’t forge or San mai steel . Greg Cimms has San mai’d the steel I used except for the San mai
SG2 I got from Takefu, the 10V San
Mai I get from Dan Hildebrand, and the Elmax San Mai I get from Chad Nichols. None of the three American smiths I named have been able to San Mai M4. But I’m sure they are not experienced enough for you to qualify as being up to the standards of the great and all powerful Oz.

So, back to you, who has had success San mai cladding M4?


----------



## DevinT (Nov 10, 2018)

I have. I’ll post a pic when I get back from out of town. 

Hoss


----------



## pennman (Nov 10, 2018)

DevinT said:


> I have. I’ll post a pic when I get back from out of town.
> 
> Hoss


PM sent. Thanks!


----------



## chefcomesback (Nov 10, 2018)

pennman said:


> Yes, I have heat treated knife steel. But I don’t forge or San mai steel . Greg Cimms has San mai’d the steel I used except for the San mai
> SG2 I got from Takefu, the 10V San
> Mai I get from Dan Hildebrand, and the Elmax San Mai I get from Chad Nichols. None of the three American smiths I named have been able to San Mai M4. But I’m sure they are not experienced enough for you to qualify as being up to the standards of the great and all powerful Oz.
> 
> So, back to you, who has had success San mai cladding M4?



Yes Australia has very high standards in knife making , I am sure you are aware of the all successful kitchen knife makers we have , besides talent what Australia does best is if someone is coming out with bs we call it out , on the spot .


----------



## samuraistuart (Nov 10, 2018)

As far as sharpening m4, diamonds do make it easier. Silicon carbide does quite well too. Ceramics work well enough. Aluminum oxide struggles a little bit, but at the lower grits they do fine. Higher grits AlOx struggles. It’s nothing to touch up 64hrc m4 with a ceramic rod. 

I do make knives, but rarely in CPM m4. It’s not an easy steel to work with. Demanding heat treat and is just a pain to hand sand.


----------



## DevinT (Nov 10, 2018)

This is from a big vegetable clever I made about 15 years ago, had to dig it out and take the pic. Core is cpm-M4 with stainless damascus clad. I did a bunch of M4 clad back then, I've not done much since. I've laminated lots of different steels, carbon, low alloy, tool steel, high speed, stainless, high alloy stainless, etc., A2-Z2.

Hoss


----------



## pennman (Nov 10, 2018)

This is from a big vegetable clever I made about 15 years ago, had to dig it out and take the pic. Core is cpm-M4 with stainless damascus clad. I did a bunch of M4 clad back then, I've not done much since. I've laminated lots of different steels, carbon, low alloy, tool steel, high speed, stainless, high alloy stainless, etc., A2-Z2.

Hoss[/QUOTE]

That’s just gorgeous!


----------



## Von blewitt (Nov 11, 2018)

Awesome Hoss! Can we see some more pics of that one please!
It's not for sale is it?


----------



## mb> (Nov 11, 2018)

Speaking of @samuraistuart... this little M4 hunter has ended up being one of my wife’s favorite kitchen knives. It’s so light, and the handle is unusually thin which she likes. The blade is unusually thin, which I like! 

M4 has proven to be pretty wife-proof, which is a testament to toughness lol. Hasn’t left the kitchen since I received it.


----------



## Barmoley (Nov 11, 2018)

My 150 mm petty/utility works very well too. I am very impressed with the steel and the heat treat. It is a petty so different use from a larger knife.


----------



## crockerculinary (Nov 11, 2018)

pennman said:


> That’s just gorgeous!



impossibly gorgeous?


----------



## pennman (Nov 11, 2018)

crockerculinary said:


> impossibly gorgeous?


Obviously not impossibly. But uncommonly gorgeous, yes.


----------



## crockerculinary (Nov 11, 2018)

Redacted. Not in grade school anymore.


----------



## dough (Nov 11, 2018)

What is the name on Barmoley and mb’s Knives it’s too blurry in the pictures?


----------



## Barmoley (Nov 11, 2018)

Stuart Davenport @samuraistuart


----------



## samuraistuart (Nov 11, 2018)

Devin, that is a nice looking stainless damascus pattern! Curious...what are the 2 (or more) stainless steels you used to clad the CPM M4 with? AEBL and 303?

(Glad you guys are enjoying those knives! Makes me want to do more in CPM M4, it is such a great steel).

Dough....the maker's mark is mine. "S Davenport".


----------



## dough (Nov 11, 2018)

Thank you I thought I had seen it before


----------



## panda (Apr 23, 2019)

i would love to try a gyuto in powdered m4 based on the experience of using my spyderco military in that steel. the edge lasts forever and is not bad on stones.


----------



## Barmoley (Apr 23, 2019)

Me too, me too based on many spydercos and petty from Stuart. Thinning would be a huge PITA I suspect, so would have to be very lasery to not ever have to thin, which sucks from the food release stand point, or has to be a san mai construction.


----------



## samuraistuart (Apr 23, 2019)

You would absolutely love a gyuto in M4 (CPM). It would be pricey, as working the stuff isn't easy. The edge retention is excellent, as expected. M4 is also fairly tough. Well, tough for a steel that has a fairly high carbide %, and at 64HRC. The petty I have gets babied. Wooden cutting board, and my cutting technique is such that I try to not let the edge even contact the cutting board. The knife never sees any real abuse at all, usually just protein cutting chores. What I like about M4 is that it seems to retain a bit of "bite" at the edge right off the stones, and keeps it for a LONG time. After a year or so of weekly use, I decided to sharpen it again the other day. It certainly didn't need it by any stretch, but I wanted to! (along with a Miyabi Santoku in MC66...ZDP-189). Both knives were honed on DMT plates, Fine, Extra Fine, and Extra Extra Fine (3 micron). 15° per side. I keep saying it, but it's worth repeating, M4 is extremely wear resistant. It is by far the most wear resistant steel I have worked with (never have used the S series vanadium bombs like 90V or 110V, etc). Thinning such a blade would be a very labor intensive task, unless you have access to a belt grinder or diamond plates. Hand rubbed finishes are just pure torture. It simply laughs at sandpaper. 80 and 120 grit is like having a root canal. Anything above 120 grit (like 220, 400) is like having a knee cap blown off. 800 grit? Fuggit about it. I take M4 to 400 grit, and that's enough. Food release has never been a real issue for me, by that I mean I don't pay too much attention to it. Super thin knives will have a tendency to hold on to food, but there are ways around it. "S" grind is one way, but not easy on a thin blade. Also having a slight convex in the grind helps as well, with the convex just above the cutting edge. I do all grinds as "full flat", and keep them flat when doing the hand rubbed finish in the coarser grits. As I get to 400 grit and up, I use a softer backing and try to establish a convexity above the edge, but in all reality, the grind is pretty flat.


----------



## Barmoley (Apr 23, 2019)

I don't baby your CPM-M4 petty, I don't abuse it, but no babying at all. It had plenty of board and even bone contact in more than 1.5 years I've had it, nothing stupid, but just normal use without concern for the edge. It is fine no chipping or rolling or anything, so I'd say that CPM-M4 the way you make it is plenty tough and edge stable for a kitchen knife. Would love it in a gyuto, even though I don't generally like flat grinds in gyutos, but if it doesn't stick to food too much then it could work. Gyutos also experiences more force on it than a petty, but I suspect it would be fine with appropriate geometry.


----------



## pennman (Apr 27, 2019)

I make a bunch of gyutos in M4. Edge holding is as described above. It is much harder to work than most other steels. It’s got that fabulous Carbon “feel” when cutting. I do hand rubbed finishes up to 600 and sometimes 800 grit if I feel like it. 

I made my eviscerating scalpel from M4 and was able to 7 complete eviscerations before needing to sharpen it. Impressive edge holding.


----------

