Compare M390 and M4 for me. Lets just talk about steel for Polished-Edge-Sharp

Wowbagger

Wowbagger

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I almost titled this "Which is better M390 OR M4 ?" but figured I better not start out on the wrong foot.

So
I KNOW I like Benchmades M390 . . . love it, love it . . . stays sharp for me for ever for what I use it for.

Then I got this idea in my head from reading that M4 was a bit better at resisting wear at the edge / staying sharp.

Then I read that it has been around for ever and there are better high speed steels . . . should I wait for those to show up in knives ?
I'm going crazy here.:confused::eek:

I am looking at buying a new knife : S90V, M390, M4, S30V.
Yes several knives. The S30V is about to win out because I want to try the DLC coating. The others don't seem to be available with that coating. Then I tell myself to hold out and wait for it to be applied to M390 or M4
I want the DLC coating for reduced friction not stealth.
Speaking of stealth are the latest Para 2s in all black still coming with black screws ? ?? I read somewhere the newest ones are coming with bright polished screws like the Military. I am all about the ALL BLACK Para IN ADDITION to the knife I am talking about bellow, see bullet list, and may "put up with" the S30V to get the all black Para.
I'm going crazy here.:confused::eek:

The knives on the list are : Para 2, BM 940, BM 810 Contego (but will wind up grinding it thinner and I am not wild about the handle shape (rough texture is OK though).

Ultimate knife would be :BM 940
  • Ground a bit thinner
  • M4 ? ? ? ? ? ?
  • DLC coated (real dlc . . . is BM's coating something else ? ? ? ?)
  • G10 scales or sculpted and textured Ti in a very similar shape to the BM 940.
  • Axis lock
  • Blade length at least 3.5 inch but not over 4 (would consider shortening blade )

Ha, ha the Spyderco Mike Draper C171TIBLP Folder, VG-10 Steel, Titanium Handle knife is pretty close but I don't want the spider webs and it is "only" VG-10 and it is some serious money at that.

Lets just talk about steel for Polished-Edge-Sharp for now.
Cuts some rubber coated cloth and cardboard and then can still be "shave sharp". Parenthesis for the gentleman who assures us we aren't talking REAL shave sharp. I'll buy that . . . so . . . I am talking : still scrapes hair off my arm well enough to make me grin.
and
catches on my thumb nail with out a rolled edge too much anywhere at all much. Now that we got the High Tech engineering terminology out of the way . . .
What do you say ?

I don't give a hang about rust resistance or impact resistance (zero batonning) just sharp and high wear.
Forget about ease of sharpening.

please . . . compare M390 and M4 for me.
Knife suggestions based on the above.

I may just take a big O' flyer and just get Boker's black ceramic Ti handled knife for fifty bucks. It is pretty darned close to what I want as well.
Might chip in use . . . I am set up to sharpen steel not ceramic . . .
I'm going crazy here.:confused::eek:
 
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I just got a nice M4 folder from the custom configuration shop from benchmade. My first non-auto from them. Very cool knife. I would check that out. You can choose from 6 steels, two of which are 20CV(M390) and CPM M4. Both steels are awesome!

So M4 and m390- I find edge holding very similar to the point that you won't tell a difference in everyday life. You would only notice in controlled tests. The main difference I find in them is they wear differently. Hard to explain. It seems like no matter how polished the edge is, M390 will be more aggressive, and keep that bite longer, and it holds on to a great working edge. M4 seems to be a smoother cut, and very slowly smooth away to being not sharp. So I would say equal, but different. So you have to decide whether you want toughness(M4), or Corrosion resistance(M390/20CV/204P). Just my opinion from using them, I know everyones experience is different!

As for other high speed steels. I have recently fallen in love with high wear resistant tool steel. K390, oh my god it is amazing!!! CPM 10V, and K390. I wish more folders were made with these steels! Not HSS, but they are beyond amazing! Hoping I can get at least one more medium size folder in K390, then I will be happy!

Good luck choosing your knife!
 
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i love both and so should you. Get you some M4!:D j/k

I don't know if it's me but M4 loses it shaving sharp edge pretty quick but will keep a working edge for a pretty good long while.

I have a couple of blades in M390 but I don't edc them enough to have much of an opinion.

I'm high on S110v at the moment.
 
There is a lot going on in your post, and I don't know that and I can address all your questions, but in my experience, and someone who knows more may correct me, M4 will hold an edge longer in certain applications. It is a bit below M390 in wear resistance, but if you cutting something with a lot of abrasive inclusions, like cardboard, M4 seems to hold an edge longer because the added toughness. I love both and have numerous knives in both steels. You won't noticeably better for folding knives than those two IMO.

S30V is great too and is easier to sharpen. I haven't heard anything about new DLC PM2s coming with satin hardware, and I doubt it is true. DLC seems to have the opposite effect for me; it seems to increase drag. All the knives you mentioned are great; I prefer the PM2 but you may not. You can't go wrong with your choices though. You win the award for the most ADHD post I've seen in awhile with this one, so I can tell you are excited lol! Good luck and make sure and post when you make your decision!
 
M390 but I don't edc them enough to have much of an opinion.

I'm high on S110v
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Oh man use the M390.
I found my one example of S110V to be Meh.
Then I bought M390, not paying attention to the steel just wanted that knife, and it was a wow moment.

CPM 10V
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The other day I was almost to the point of buying a Spyderco Farid Mehr K-2 just so I could try the 10V.
I would wind up regrinding that ginormous blade into a shape more to my use (I have no idea what to do with all that curve down by the point) . . . and that would just be a shame on such a beautiful and $$$ knife so I resist

But there are still moments when . . .
 
jst,

There is a lot going on in your post
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ha,ha
yah . . . a . . . sorry
I realized that and started another thread about the Para S30V at any rate.
 
If you are looking for an M4 blade that is coated, ZT makes an exclusive ZT0770 for an online dealer that meets your criteria.
 
You win the award for the most ADHD post I've seen in awhile with this one, so I can tell you are excited lol! Good luck and make sure and post when you make your decision!
Click to expand...

hahahaha
I just got too much sleep after a week of none.
Normally I am terrier like in my one pointed focus. Or as Heminway said "I am like a pig when I'm working".
But as I said I am going crazy here.

Joni Mitchel nailed it when she said "The kind of crazy you get from too much choice".
 
DLC seems to have the opposite effect for me; it seems to increase drag
Click to expand...

Hmmm
maybe DLC is best in motor parts metal to metal.

THANKS ! THAT IS HUGELY INTERESTING AND ENLIGHTENING.

I can kind of imagine how that could be true without actually experiencing it.
 
M4 hands down, it's only drawback is corrison

It has the toughness and stability of A2 with the increased wear resistance in the playing field of m390 and ZDP189 but not at the s90v and above level

It also sharpens to a very keen edge.

I had a Gayle Bradley in M4

It was my first super steel.

I sold it and haven't had a knife that could hold the same high sharpenes as long.

I currently own a m390 765

I've been pleased with its high sharpenes but it takes mirco chipping during use. Same with Elmax.

M4 doesn't do that
 
Sonnydaze,

Ankerson tests
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Oh yah . . . I tend to skip the original tests and just look at the 400 grit edge tests.
There was the info all along !

Thank You !

PS: I wonder why the 3V was left out of the 400 grit edge tests; but I guess that is for a different thread. I have really been looking at 3V lately but have narrowed my favorite steel down to M390 and possibly M4 but from what I am reading here today I think I may as well stick with M390 for what I like in a steel.
 
Oops,

Hi DeadboxHero,

You snuck one in while I was typing.

M390 chipping
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I don't find that at all with my one blade that I have.
Thanks for the vote for M4. Sounds like it can be as good as I originally had read it was.
 
I have two BM in M390, but have not used them enough to form an opinion.

What makes M4 my favorite is based on some surprising results. For example, not long after I got my Bradley, I was at a wedding reception. They handed me the bouquet (couple dozen roses) and asked me to cut the stems shorter. I thought it would be a piece of cake. But it took a lot more force than I expected to cut through the stems. When i was halfway done, I took a closer look, and discovered that each stem was wrapped with green florist wire. I was cutting the wire along with the stems. Worried that I had done damage to my fine edge, I was very pleased to see only one very very tiny indentation on the edge. One quick sharpening and it was back to a clean edge.
 
M4 gets insanely sharp fairly easy...it takes a much keener edge then m390. If only it was stainless.

Sent from my SM-G935V using Tapatalk
 
I have a Benchmade 581 Barrage in M390, and a Gayle Bradley 2 in CPM M4 - in my experience M4 holds an edge better than the M390, gets sharper than M390, and holds the razor edge longer. And I like patina :)
 
And I like patina
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I'm with you there. I am looking forward to some M4 . . . tarnish and all.

I must say I am quite surprised by the comments that M390 does not take as sharp an edge.
One of its "big things" is that it can take a high polish. For me that translates into an effortless push cutting edge. My one M390 came with . . . came with mind you . . . as keen an edge as I could ever hope for from a factory sharpened knife. Not that I couldn't improve it but it was / is a fearful and powerful thing to be hold.

M4 is going to be an order of magnitude better ! ! !
? ? ? ?
! ! ! !

Sweeeeeeet !
 
Have you EDCd an Osborne 940? Get one and carry it for a few weeks. Then, decide what really needs to be changed, or left alone. Don't be suprised if the stock BM940 in S30V with green Al scales isn't just about perfect as is.
 
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