Bohler K390 v M390

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Mar 12, 2012
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I would like to get some opinions on those two steels:


K390 64-65 HRC

Carbon - 2.45%
Chromium - 4.15%
Cobalt - 2.00%
Molybdenum - 3.75%
Silicon - .55%
Vanadium - 9.00%
Tungsten - 1.00%


M390 61-62 HRC

Carbon - 1.90%
Chromium - 20.00%
Manganese - .30%
Molybdenum - 1.00%
Silicon - .70%
Vanadium - 4.00%
Tungsten - .60%


One is being carbon another is stainless which would make a better knife?
What is your take on stain resistance of K390?
 
IMO, the M390 with the much greater chromium content will be much more stain resistant. The K390, higher carbon content and hardness, will be more brittle, more likely to chip than roll the edge, not as tough, harder to sharpen but will hold an edge longer.
Ankerson can correct me as necessary. :)
 
I would guess because of higher vanadium content K390 would be tougher.

So K390 would be more difficult to sharpen than M390? Is that the general consensus?
 
You will have to be a lot more specific in your question. What does better knife mean? Better for what? Folder? Traditional pattern? Fixed blade? Utility, chopper, camp, self defense? A far as sharpening is concerned, power systems or guided systems have taken all the "harder to sharpen" issues out of the equation. Paper wheels, Wicked Edge, and Edge Pro can sharpen absolutely any steel to a hair popping edge. The skill of the sharpener is what may or may not allow this to happen.
 
Ok

fixed blade
slicer type utility blade about 3 to 4 inches long
flat grind
convex edge
to be sharpened on compound loaded leather strop

intended use: light camping chores, food prep etc.
 
Both will make great knives. K390 is not readily available though and is an absolute pain to work with. However it cuts really aggressively and if you maintain the edge it will stay sharp for months at a time.

M390 is my favorite steel at the moment. Its an aggressive cutter, has great edge retention, is stainless and tough. Also its available and worlds easier to work.
 
I'm partial to M390 for food prep, and it will do your general purpose cutting beautifully as well.
It is also going to be a bit easier to maintain with a strop.
 
You will have to be a lot more specific in your question. What does better knife mean? Better for what? Folder? Traditional pattern? Fixed blade? Utility, chopper, camp, self defense? A far as sharpening is concerned, power systems or guided systems have taken all the "harder to sharpen" issues out of the equation. Paper wheels, Wicked Edge, and Edge Pro can sharpen absolutely any steel to a hair popping edge. The skill of the sharpener is what may or may not allow this to happen.
I disagree, harder to sharpen issues are not taken out of the equation ...
Ease of sharpening on non powered equipment, or common whet stones can be desireable when one is away from civilization and is limited to a rucksack for example and one may only have a pocket stone.
Seems like all these backyard testers and Internet experts hype the hardest stainless super steels, but there are many who have experience who prefer toughness and ease of sharpening that contradicts the thread/rope/card board cutting whizzes.
 
K390,k294, 10v are all similar in composition. K390 and k294 are 3rd generation pm steels, while 10v is not quite as refined. They are all too similar to be noticed in a knife blade and are about as good as it gets for edge holding while being tough enough that it won't chip out to easily.
 
K390,k294, 10v are all similar in composition. K390 and k294 are 3rd generation pm steels, while 10v is not quite as refined. They are all too similar to be noticed in a knife blade and are about as good as it gets for edge holding while being tough enough that it won't chip out to easily.

So how do they stack up to M390?
 
I disagree, harder to sharpen issues are not taken out of the equation ...
Ease of sharpening on non powered equipment, or common whet stones can be desireable when one is away from civilization and is limited to a rucksack for example and one may only have a pocket stone.
Seems like all these backyard testers and Internet experts hype the hardest stainless super steels, but there are many who have experience who prefer toughness and ease of sharpening that contradicts the thread/rope/card board cutting whizzes.


No I doubt they forget sharpening, and non powered equipment...

It's just we know how to sharpen to begin with and know it doesn't take that much effort to maintain an edge on even the highest alloy super steels. ;)
 
A simple diamond pocket stone can solve m390, k390, and just about any sharpening problem out in the wilderness.
 
Basically both are super steels, if you want to give up corrosion resistance and ease of sharpening in exchange for even better edge holding go for K390, if you want to give up some edge holding in exchange for corrosion resistance and some ease of sharpening go M390, if it were me I'd go K390, just because I don't have anything in K390 yet, and have several knives in M390 (which I like a lot) I do have two custom fixed blades (one 5" blade one 4.5") in CPM-10V which as mentioned is similar and they are excellent.
 
No I doubt they forget sharpening, and non powered equipment...

It's just we know how to sharpen to begin with and know it doesn't take that much effort to maintain an edge on even the highest alloy super steels. ;)
Ease of sharpening doesn't mean one has to lack know how
Some Blade materials are just easier to maintain with a simple pocket stone than others. I know old timers who didn't like 440C blades, and I'd bet they're not collectors or posting all day on BF, but it doesn't invalidate their experience. I don't know many people who enjoy sharpening like I do they are just users of simple blades ...:rolleyes:
 
Basically both are super steels, if you want to give up corrosion resistance and ease of sharpening in exchange for even better edge holding go for K390, if you want to give up some edge holding in exchange for corrosion resistance and some ease of sharpening go M390, if it were me I'd go K390, just because I don't have anything in K390 yet, and have several knives in M390 (which I like a lot) I do have two custom fixed blades (one 5" blade one 4.5") in CPM-10V which as mentioned is similar and they are excellent.

Best answer yet. :thumbup:

I had a fixed blade from OTK in K390 and it was extremely sharp and stayed that way.
I have PM in M390 and like that steel a lot

for light camp duty both would be great but stainless is a nice property to have
besides I will be packing some 3V steel too
and plan to get another fixed blade in M4 (which supposed to be similar to K390 right?)
 
K390 fits between K294 (A11) and S690 (M4). It has better edge holding than M4 and is tougher than A11.

I personally think K390 is tougher than M390.

Chuck
 
Ease of sharpening doesn't mean one has to lack know how
Some Blade materials are just easier to maintain with a simple pocket stone than others. I know old timers who didn't like 440C blades, and I'd bet they're not collectors or posting all day on BF, but it doesn't invalidate their experience. I don't know many people who enjoy sharpening like I do they are just users of simple blades ...:rolleyes:


There must be some issue then if they are having issues sharpening those steels wouldn't you think.... ;)

There is knowing how and then there is really knowing how and having the proper equipment to maintain and that doesn't mean power equipment or guided systems either..

It takes no longer to maintain a blade in something like CPM 10V, CPM S90V or CPM S110V than it does something like 1095 using the PROPER equipment, in reality it takes LESS time because one won't have to be touching up the blade as often or at all in the field.

Time is measured in seconds here as in less than a minute maintaining them in the field.

This is coming from someone who uses those types of steels on a daily basis and has a vast experience with them.

Proper equipment that is easily carried and light weight would be something like a small Silicone Carbide loaded strop or a ceramic rod, both are nothing fancy, high tech or expensive.

All that is really needed is the above and the real knowledge of how to touch up a blade.

I personally never use diamonds to sharpen because they IMO aren't needed....

That said it will take more effort to get the bevel set on the high alloy steels than on the simple ones, but once that is done and that is important, they are really easy to maintain.
 
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I disagree, harder to sharpen issues are not taken out of the equation ...
Ease of sharpening on non powered equipment, or common whet stones can be desireable when one is away from civilization and is limited to a rucksack for example and one may only have a pocket stone.
Seems like all these backyard testers and Internet experts hype the hardest stainless super steels, but there are many who have experience who prefer toughness and ease of sharpening that contradicts the thread/rope/card board cutting whizzes.

Well, I can't speak for anyone but myself. I'm not a backyard tester, internet expert, or cutting board whiz. What I do know is that if M390 is sharp to begin with, it has plenty of edge holding to handle a weekend warrior hiking trip/walking path, and not need to be touched up after every task. Some of the knives I've used have cut literally thousands of yards of cardboard, all kinds (single and double walled). The conclusion that this got me to, is that some steel hold an edge better than others (M390 and Elmax are great examples). That said, if I were n the middle of nowhere, those same knives would have had edges that wouldn't need a touch up in the field, under basic expected uses.

My initial point in regards to sharpening was that people are no longer only limited to using a single grit stone (like our grandfathers). People have options that can make short work of putting an atom splitting edge on just about any steel alloy you can come up with. Yes, there are also people that like to sit on their porch and sharpen their knives with stones . It has a therapeutic effect as reported by many. But that isn't exactly what was being referred to. Smiths, Lansky, Spyderco, and Gatco are a few companies that make perfectly serviceable and portable sharpening systems for the field. We aren't limited to a sngle abrasive stone unless we want it that way.
 
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