CPM M4 vs K390

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Surfingringo
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Re: CPM M4 vs K390

#21

Post by Surfingringo »

Evil D wrote:
Ncmiked wrote:I think it's easier to get that sticky sharp feel with K390.
I haven't tried K390 yet but I've had a few in M4 and it's one of my favorite steels, partly because of how easily I can get it really sharp so I find this to be pretty encouraging.
I fully agree and this discussion is making me want to give k390 a go. I really should have picked up one of those Urbans just to play with the steel.
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elena86
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Re: CPM M4 vs K390

#22

Post by elena86 »

Surfingringo wrote:
Evil D wrote:
Ncmiked wrote:I think it's easier to get that sticky sharp feel with K390.
I haven't tried K390 yet but I've had a few in M4 and it's one of my favorite steels, partly because of how easily I can get it really sharp so I find this to be pretty encouraging.
I fully agree and this discussion is making me want to give k390 a go. I really should have picked up one of those Urbans just to play with the steel.
Why don't you ? They are quite available at a few vendors and at 65$ it's a steal.Trust me, you'll love the steel and the Urban is a superb compact little folder.K390 is second close to CPM-Cruwear as my favorite non-stainless steel.
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Re: CPM M4 vs K390

#23

Post by Doc Dan »

Surfingringo wrote: I fully agree and this discussion is making me want to give k390 a go. I really should have picked up one of those Urbans just to play with the steel.
KW has them in stock. I, and a lot of others, feel this is one of the best purchases we have made. It is a great design, but the steel kicks it into high gear.
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toomzz
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Re: CPM M4 vs K390

#24

Post by toomzz »

Sounds all promising, the so far experiences with K390. I wonder how Maxamet fits in next to M4 and K390. I finally bit the bullet and reprofiled my edge from 38 back to 30 degrees inclusive. Took a while to get there, but my Police is freaking slicing-hairsplitting now...
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Re: CPM M4 vs K390

#25

Post by dsvirsky »

Doc Dan wrote:I, and a lot of others, feel this is one of the best purchases we have made. It is a great design, but the steel kicks it into high gear.
I have to agree. The Urban is an excellent design on its own, but with K390 it becomes a truly outstanding value at only $65.
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Re: CPM M4 vs K390

#26

Post by vilePossum »

Seriously, get one! I actually prefer K390 right now as it doesn't rust nearly as fast as m4.
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Re: CPM M4 vs K390

#27

Post by TomAiello »

Doc Dan wrote:
Surfingringo wrote: I fully agree and this discussion is making me want to give k390 a go. I really should have picked up one of those Urbans just to play with the steel.
KW has them in stock. I, and a lot of others, feel this is one of the best purchases we have made. It is a great design, but the steel kicks it into high gear.
Ditto.

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Re: CPM M4 vs K390

#28

Post by jpm2 »

I'm really surprised there's K390 Urbans still in the retail shops.
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Re: CPM M4 vs K390

#29

Post by Ncmiked »

I used my K390 to cut holes in aluminum gutters for the down spouts, steel didn't blink.
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Re: CPM M4 vs K390

#30

Post by jpm2 »

toomzz wrote: I wonder how Maxamet fits in next to M4 and K390.
I have 2 maxamet blades. I can engrave all my m4 and k390 blades with them.
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Re: CPM M4 vs K390

#31

Post by TomAiello »

I wish there was a maxamet UKPK, though. I don't have any Maxamet for EDC in non-locker jurisdictions.
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Re: CPM M4 vs K390

#32

Post by toomzz »

To sum up our experiences sofar K390 is more oxidation-resistant than M4, K390 holds an edge longer than M4, but M4 is tougher. K390 is a little more difficult to sharpen and more wear-resistant, right? How about the Rockwell hardness on both?

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30 degrees inclusive ;)
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Re: CPM M4 vs K390

#33

Post by curlyhairedboy »

jpm2 wrote:I have 2 maxamet blades. I can engrave all my m4 and k390 blades with them.
this is quite impressive!
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Re: CPM M4 vs K390

#34

Post by Chumango »

I guess folks have different experiences. I don't have either steel, but my brother has the Urban in K390 and his experience is that K390 is more prone to corrosion than M4.
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Re: CPM M4 vs K390

#35

Post by Evil D »

Chumango wrote:I guess folks have different experiences. I don't have either steel, but my brother has the Urban in K390 and his experience is that K390 is more prone to corrosion than M4.
Well as far as rust goes I think the person is as much of a variant as the steel. There are guys here who can't live with anything less than H1 because they can rust S110V just from carrying it in their pocket. Other guys seem to be able to keep carbon steel from rusting even in salt water. Care plays as much a role as something as simple as the potency of a person's body sweat.
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Wanimator
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Re: CPM M4 vs K390

#36

Post by Wanimator »

Mine must be fairly non corrosive because HAP-40 doesn't seem to have issues in my pocket. I've had spotting on S30v frequently and AUS-8 once though...
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Re: CPM M4 vs K390

#37

Post by Chumango »

Evil D wrote:
Well as far as rust goes I think the person is as much of a variant as the steel. There are guys here who can't live with anything less than H1 because they can rust S110V just from carrying it in their pocket. Other guys seem to be able to keep carbon steel from rusting even in salt water. Care plays as much a role as something as simple as the potency of a person's body sweat.
True, but for the same person who uses both M4 and K390 and sees more staining with K390, it is a comparison of steels, not of body chemistry between different people.
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Re: CPM M4 vs K390

#38

Post by Evil D »

Chumango wrote:
Evil D wrote:
Well as far as rust goes I think the person is as much of a variant as the steel. There are guys here who can't live with anything less than H1 because they can rust S110V just from carrying it in their pocket. Other guys seem to be able to keep carbon steel from rusting even in salt water. Care plays as much a role as something as simple as the potency of a person's body sweat.
True, but for the same person who uses both M4 and K390 and sees more staining with K390, it is a comparison of steels, not of body chemistry between different people.

Yeah that's true, I guess it's possible their sweat reacts differently to steels than other people's? I think it's most likely to do with more random things. We see the same conflict of opinion sometimes with edge retention and toughness too.
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Re: CPM M4 vs K390

#39

Post by Chumango »

In my brother's case it was not a matter of sweat, it was a matter of cutting different things and seeing staining as a result. In his use, M4 is more corrosion resistant.
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Re: CPM M4 vs K390

#40

Post by jpm2 »

What M4 blade does your brother have.
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