Spyderco Forums

What blade steel is K390 comparable or equivalent to?

A11 class of steel

I think it's in the S110V range, probably more wear resistant, but it doesn't have as much stain or rust resistance.

Any comparison I can make would be to explicit for this forum. Its amazing. A combo of S110V's cuttablity, M4's toughness, super blue's patina and cru-wear's sharpenablity.

Composition wise it seems to be a modified version of A11 cold work tool steel.

As far as how it performs, sharpening is about the same as lower alloy carbon steel (though it's tempered rather hard in the Pingo!) but edge retention seems more like M4.

I think this will be a good steel. At first I was a bit confused as to why this choice of steel in a knife meant for police and others, that would be exposed to the elements and probably not cleaned often. But, I later decided that 1] It is a steel we have not seen a lot of and 2] other properties such as toughness and impact resistance may have weighed in on the decision.

slick228 wrote:What blade steel is K390 comparable or equivalent to?

10v, s110v, Maxamet, Vanadis 10, Rex 121, the super duper carbide steels.

I'm guessing Spydie's using it in the Police to push sales of that model.

M4 on steroids

It's composition makes it comparable to the a11 steels. K390 is the closest to A11, 10v or K294. S90V is the closest stainless steel to K390 that I am aware of. K390 is a very wear resistant steel and should fall into a similar performance class as S110V but composition wise the S110V has a lot more in it and it is stainless.

Short answer, it is the European equivalent of 10v/A11.

Doc Dan wrote:I think this will be a good steel. At first I was a bit confused as to why this choice of steel in a knife meant for police and others, that would be exposed to the elements and probably not cleaned often. But, I later decided that 1] It is a steel we have not seen a lot of and 2] other properties such as toughness and impact resistance may have weighed in on the decision.

Hi Doc,We make quite a few designs for the Law Enforcement market at this time, so the design for Police use is necessarily the case anymore, like it was in 1984. I designed the Police 4 to include what I would like in a knife, more than what a LEO might like. It's still a kissing cousin, and large for most people. I widened the blade, enlarged the hole and selected a steel that I like to use. The design's success in the marketplace is unknown at this time. But I get to have one. :p

sal

I get to have one too!

+1

If I ever figure out how to find the money for the others, too... :p

sal wrote:

Doc Dan wrote:I think this will be a good steel. At first I was a bit confused as to why this choice of steel in a knife meant for police and others, that would be exposed to the elements and probably not cleaned often. But, I later decided that 1] It is a steel we have not seen a lot of and 2] other properties such as toughness and impact resistance may have weighed in on the decision.

Hi Doc,We make quite a few designs for the Law Enforcement market at this time, so the design for Police use is necessarily the case anymore, like it was in 1984. I designed the Police 4 to include what I would like in a knife, more than what a LEO might like. It's still a kissing cousin, and large for most people. I widened the blade, enlarged the hole and selected a steel that I like to use. The design's success in the marketplace is unknown at this time. But I get to have one. :p

sal

Hey, thanks for the information, Sal! This will be my first Police. I am already saving up for it. I do think it is an interesting steel choice and cannot wait to try it out in this knife platform.
Besides the steel and other improvements you mentioned, the weight reduction also contributed to my decision.

I have been using K390 from the start ever since it was introduced by Bohler and I got some small samples to try. A bit of history is that it is the European version of CPM 10V but not the exact chemistry (about 1% less V plus small addition of a few others). That is because the CPM 10V chemistry was protected by patent at the time. If you check the K390 data sheet it claims that the bit less V gives K 390 a little boost in impact toughness. It also can be heat treated at a lower temp. than 10v. So it is pretty much the same as the A11 grade but different in a few small details. It is hard to tell the difference between CPM 10v and BU K390 in the real world in my experience. I like both grades and they are the base line (along with Vanadius 10 and K294) from which I measure wear resistance. The 5 chrome is there to make them all air hardening among other things and does not contribute much to corrosion resistance. It is going to make a killer knife in the new offering and be another classic. Phil

Thank you for adding that Phil. I got one store to open up the pre order for this and for the first time in years I'll be first on the list. This will be a heck of a knife. I'm looking forward to the lock as much as the steel. I currently have 4 Police models and really like the design but the new model checks even more boxes for me.

Joe

I've been re-profiling my K390 Mule and a SB caly 3. I've noticed that the k390 seems to take a keener edge than SB, of course that can be subjective but it gets very sharp and polishes very nicely. I also have noticed it patinas rather quickly. It is not a deep patina like super blue but it is a noticeable.

Sal,
You did an awesome job on the redesign. This is my most anticipated knife of '17.