Favorite Stainless Steel for Rough Use? Opinions on Lam. CoS versus 3V?

PM Nitrobe77 may be tougher then Vanax if both at 60hrc.

Also it should be noted that hardness and geometry play a bigger role then just the steel.

60hrc, 20dps, 0.015"-0.020" behind the edge and a spine thickness no lower then 0.100" is about the limit for PM Stainless without nitrogen. If the hardness is increased and or geometry is lowered it will fail regardless of if it's elmax or s35vn


We should do some crowd funding and get some samples to Larrin for charpy testing.

I'm curious to see what the toughest PM stainless steel is at 60hrc

Elmax is the toughest of the powder stainless steels, with the possible exception of Vanax SuperClean. If you look at the chart in the first link you provided, you'll see that Elmax, even at 59Rc, is much tougher than 440C, 154CM, CPM 154, S30V and S35VN (the other steels, except 440C, are listed by their composition names).

You can find tougher steels, but they are either non-stainless or ingot stainless that won't hold an edge as well.
 
Are S35vn and Elmax tough enough for some batoning and bone contact within reason?

Sure! 60hrc by anyone with good temperture control and sound protocols will do it just fine. Most production knives come with extra meat on them too to compensate for misuse as well, however durability is an inverse relationship with actual cutting performance. No free lunch.
as a user you have two choices

1. Don't make contact with bone (be mindful of your edge)
2. Increase edge angle to 20dps and go up if needed.

CoS vs 3V?

CoS and 3v aren't very comparable, it's like comparing a sports car to a pick up truck.
They have strengths in different areas.


I LOVE the Takefu Cobalt Special (CoS) it runs harder and you buy it for all the reasons you would buy a sports car.

3V is more malleable, little more time to sharpen. The burr is more stubborn to remove. The edge feels a little smoother as well. CoS takes a crisper edge faster but 3v is no slouch. 3v is a more durable steel and is packed with more wear resistant vanadium carbides.

You would choose 3v for all the reasons you would choose a truck.



I was new once too, so I'll go more in depth.

Carbides?

The carbides are like little marbles inside of softer structure.

All steels have carbides. Different types, sizes and hardness


This is important for understanding why some steels have PM and some don't.

3v is PM, CoS is not.


The PM process keeps carbide forming alloying elements (when at high volume) very fine when the melted steel is cooling by atomizing it so you don't have a clumpy carbide mess that would reduce the toughness.

CoS is not a PM steel but it doesn't need to be. There are less of the carbide forming elements that cause the problems that requires PM to circumvent when the steel is.being made.

The harder and higher volume vandium carbides (MC type) in 3v hit 81-83hrc while the matrix that holds them can be anywhere from 57-62ish depending on the protocol chosen

In my opinion, I feel the carbides really only show with an aggressive toothy edge (300-600grit) but people fail to understand how to create such an edge without leaving a burr or a wire edge so they miss out. Also such an edge works best by drawing the edge with light pressure across what's being cut. People that push the edge straight in to what's being cut will not like a toothy edge. The teeth will create more resistance and wedge. Hence why a 800-1500grit medium range is needed if you want more polish, push cut ability

This is why cutting wood needs polished edges yet why processing fish and game, a toothy edge is best.
Is reality we have to find the best blend based off our use and preferences and some steel definitely have better synergy with one finish over another.

I feel toothy edges and a high volume of harder carbides work great together because the deeper scratches expose more surface area and allow the carbides be more exposed and express themselves at the teeth for more for aggressive draw cuts and bite, great for fish and game.
3v can also be polished so don't feel stuck with trying to take advantage of the vanadium carbides.

Geekiod stuff aside just buy the design you like the most.

Don't get too fixated on the steel.

There are so many variables to all this stuff that honestly most of us are probably not seeing what we think is the steel but more to do with geometry, how it was used and most importantly, how well it was Sharpened.


Yet there are endless threads about The steel or the some exotic heat treatment being the magical end all be all.
Really it's the geometry, the user, and how well it's been sharpened, if the steel is decent and the heat treatment has good temperture control and protocol then it's good to go. So dont get tunnel vision.
I'm guilty of this but not blind to it, I do genuinely enjoy finding the small nuisances between the different steels in my hopeless quest for the ultimate synergy but it's an endless endeavor which is why I love it.

Regardless, asking what steel is best should be reserved for buying a full custom knife.

Buying production, you are at the mercy of what's available in a design you like, so you don't get to be picky. You don't have that luxury.




What's your favorite stainless steel for bushcrafting or other rough uses? I've heard that S35VN and Elmax can be chippy (and don't roll) and difficult to strop up in the field. I'm looking for a relatively tough steel that isn't too chippy because I plan to baton with it and it will come into contact with bone regularly.

What are your opinions with Fallkniven's laminated CoS and how does it compare with CPM 3V in terms of toughness and edge retention? Are the stainless properties in lam CoS worth the difference? The reason why I ask this is because I've been really fixated on finding a new 3V knife, but also heard that Fallkniven is coming out with new models with the lam. CoS steel in the future.
 
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DeadboxHero Wow, great insight. I'm new to a lot of this, so that was useful. It's very true what you said about the design. Design and edge geometry are super under-rated. Throw-in some heat treat and you have way more determining factors than the steel. Good steel is only one aspect of a good knife.
 
A few minutes ago I took the leap and bought an F1 in CoS. $199.95 So yeah guys, pray for me. I have high hopes for the knife, based on the incredible reputation of the F1, and almost 100% positive feedback about CoS steel. It sounds like CoS looses nothing to VG-10, and gains the ability for a finer edge, better edge retention, and probably some toughness. I've seen CoS steel cut through bricks and steel and not chip, so I'm pretty confident. It's still a brittle steel compared to good carbon steels, but I think it will serve me well. I'll certainty post with any observations after use.

Wow, this is my old thread. I’ve since bought the new F1 in CoS and used it a couple times. It has rusted and pitted to hell after mild use. I’ve mailed it back to fallkniven and they are investigating the issue. Pictures and details later.
 
Pitted? Never seen that on any Japanese stainless laminate. Lookin forward to your pics.
I use my VG10 F1 on saltwater fishing trips and always make a note to clean that up. Discoloration is evident by the time I get home. On freshwater trips I carry my 3G F1 and I've even had it sitting in water overnight. Not a sign of corrosion.
 
Wow, this is my old thread. I’ve since bought the new F1 in CoS and used it a couple times. It has rusted and pitted to hell after mild use. I’ve mailed it back to fallkniven and they are investigating the issue. Pictures and details later.
Yikes... sorry bud. Looking forward to hearing that they resolved the situation and what the *&^% was going on with your F1.
 
Wow, this is my old thread. I’ve since bought the new F1 in CoS and used it a couple times. It has rusted and pitted to hell after mild use. I’ve mailed it back to fallkniven and they are investigating the issue. Pictures and details later.

Wow, that’s unexpected. The sides are 420J2. That stuff is hard to rust. Something went very wrong making that knife.

I’ve only had my new F1 CoS in use on dry wood, and wet it to sharpen off the factory edge on water stones. No trouble yet, but I might throw it in a bowl of water just to see.
 
I've had my F1 CoS for about 15 minutes now. I saw activity on this thread and was like, "Oh, perfect timing!" Then I saw "rusted and pitted to hell." :(:(
 
I have a Fallkniven PXL Work Horse folder for nearly 4 years now and it never rusted.
The steel is awesome.
Hah! SNAP!

I was just about to post pretty much exactly the same thing. :thumbsup:

I can’t imagine what happened with that poor guy’s F1 Pro, but my PXL-WH gets used for the most part on mountaineering/wild camping expeditions, which means getting very wet and often staying wet for days here in the UK. Never seen a speck on it.
 
I feel better now. Not that I was really concerned...I've never heard of rusting problems with CoS. I'm more interested to see if it micro chips. I've heard so many horror stories about VG-10 chipping, and CoS is a little harder. But I haven't heard anyone mention CoS chipping, so I feel pretty good.
 
I feel better now. Not that I was really concerned...I've never heard of rusting problems with CoS. I'm more interested to see if it micro chips. I've heard so many horror stories about VG-10 chipping, and CoS is a little harder. But I haven't heard anyone mention CoS chipping, so I feel pretty good.

I’m not sure what everyone else calls microchips, but I got tiny imperfections on the factory edge when cutting hardwood on my Fallkniven Kolt, which is also CoS. One session on a 2000 grit waterstone took care of it, and it hasn’t happened since.

I didn’t get this issue on my F1 CoS.

But if it does happen, it’s likely just the factory grind. Take some metal off with a stone and you’ll likely have no more trouble.
 
So I used my F1 cos a little today whittling some dry wood and carving-up a small green stick, probably 20 minutes total. I stropped it for maybe one minute and realized it had a little bit of residue on it from the green wood. I washed it with water, dried it, and this was the result: (I couldn't figure out how to post a photo, so this is the link to Flickr).

https://www.flickr.com/photos/143439475@N02/45787877231/in/dateposted-public/

It doesn't rub off and looks suspiciously like the early signs of rust. It's also only on the CoS core, not the 440 slabs. So I'm a little concerned.
 
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Can You post a clearer pic of the edge?
It's not possible to see if it's corrosion or not.
I have 3 knives in CoS and no rust on them or any of my FK's.

BTW, I polish my edges the way DBH describes above. No signs of either rust or chipping on any of them, regardless if it's VG-10, 3G or CoS.

I have managed to get a bent edge on my PHK in 3G, but that was a user error.
I batoned it through an old piece of wood and didn't notice a hardened nail and the edge bent away leving a deep dent.
I put a lot of force behind the batoning, before noticing the hardened nail.
I was furious on myself being so stupid and uncareful.
For the amount of force I used, I 'm glad it was a dent and not worse, but I'm still mad at myself for being this stupid.

Regards
Mikael
 
I don’t know what that picture is. Stain or residue? Around here, there are small alders that leave a goo on my whittling knives when they’re green, and it dries dark purple. Have to scrub with soap to get it off.

If it stains, you can try it out by leaving water or vinegar on the blade a while and checking. Gets the residue variable out of the test.
 
I don’t know what that picture is. Stain or residue? Around here, there are small alders that leave a goo on my whittling knives when they’re green, and it dries dark purple. Have to scrub with soap to get it off.

If it stains, you can try it out by leaving water or vinegar on the blade a while and checking. Gets the residue variable out of the test.
Yeah I'll try that. It feels totally smooth and didn't rub off with water and a cloth.

Can You post a clearer pic of the edge?
It's not possible to see if it's corrosion or not.
I have 3 knives in CoS and no rust on them or any of my FK's.

BTW, I polish my edges the way DBH describes above. No signs of either rust or chipping on any of them, regardless if it's VG-10, 3G or CoS.

I have managed to get a bent edge on my PHK in 3G, but that was a user error.
I batoned it through an old piece of wood and didn't notice a hardened nail and the edge bent away leving a deep dent.
I put a lot of force behind the batoning, before noticing the hardened nail.
I was furious on myself being so stupid and uncareful.
For the amount of force I used, I 'm glad it was a dent and not worse, but I'm still mad at myself for being this stupid.

Regards
Mikael
From what I've read, polishing the edge seems to make it more chip resistant. I'm new to sharpening, so maybe some day.
 
It's really only visible in some lights, so it's hard to get it to show-up on camera. I tried washing with soap, but it doesn't seem to come-off even when scratching it with my fingernail. At this point, i would not call it rust, but it looks like the discoloration that you get on carbon steel.

I added two more pics: https://www.flickr.com/photos/143439475@N02/?
 
Looks to be located around the laminationline.
I think You should email Fällkniven and ask for advice.
Maybe it will go away with chromepolish.

Regards
Mikael
 
I'd guess that it was some stuff that got in the grooves in the steel. The ones that you can't feel or see without magnification but are very much there. Try a metal polish before you think the worst and then lose confidence in what is an excellent knife/steel combination that should last a lifetime with proper care and use. It it is indeed a sap it might be stubborn even with a metal polish and need a couple polishes. After cleaning the blade off wash off the knife with soap and water ( or a good solvent as the polish might itself eventually cause an issue if not removed) , dry, then paste wax the thing. Then, stop worrying and use it as intended. I don't have that knife but I do have a couple other knives in "Cobalt special". It's a good steel and the chances of it being a defective heat treat or bad batch is so remote that it's almost unheard of. Good luck.

Joe
 
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