Benchmade has some work to do on their M390

I believe I was one of the first to buy a M390 Grip... works fine for me. BM does do a very good job with S30V though I must say. I have a Ritter with Wilkins in S30V and that works very well too.

I think maybe M390 was a little over-hyped and that raised expectations to unrealistic levels. It is a great all round stainless steel although I would say it is not in the same league as CPM-M4 which is phenomenal.

However, it is STAINLESS with all the benefits of that and I think its a better cutlery steel than S30V. I have experienced chipping with S30V on Spyderco folders but never with M390.

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One day I hope to have an Edge Pro. Guess I just suck at sharpening, been trying to learn for a long time just get frustrated with moderns steels. Trying to sharpen D2 on DMT diamond stones drove me up the wall and beyond. Was just looking at the size of my Mini Grips and trying to picture myself using them for the type of work the OP stated and all that "need a bigger knife" stuff came to my mind. When it comes to edges RedDevil you are obviously more knowledgeable than I am. I have the nasty habit of trying to be super accurate on every sweep of the stone and end up screwing it up anyways. I hereby declare myself overruled lol

Not overruled, I was just trying to figure how it would work. I'm not really a fan of too small a knife myself. Steel should be consistent from large folders to small. Take the super and mini versions of the Emerson CQC7 or Delica and Endura as examples. As to the EdgePro, it's a nice system, with a learning curve. I've made many mistakes when trying to sharpen knives, the biggest was trying to reprofile something with too high a grit. It takes a really, really long time. :)
If you start from the lowest grit when sharpening the highly wear resistant steels it takes much less time. You will kill your 120 grit stone in short order or it will look concave at the surface. I've reprofiled a couple of Benchmade 710's in D2 and it took a while, wasn't a 10-15 minute job by any stretch, but I was being careful and trying not to rush things. The S110V was the same way, using more pressure than you would with 154CM or S30V speeds up the process, but again ends up destroying the sharpening media. What makes some guided systems (EdgePro) problematic is that it is very hard to line up the blade the exact same every time you change media.
 
What makes some guided systems (EdgePro) problematic is that it is very hard to line up the blade the exact same every time you change media.
Not if you epoxy a rare earth magnet to the underside of the base... I usually sharpen my knives on the EP with the end of the scale pressed against the side of the EP base. That way I don't have to guess.
 
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I saw that a few years ago, it was a neat idea. I never did get around to doing it to mine though.
 
The three M390 blades I have in my EDC rotation are: 710-2, ZT350 exclusive, and Blue 710 exclusive. The ZT and 710-2 stay sharp a crazy long time. The newer 710 exclusive doesn't come close to either of these. I've been carrying a Sebenza a lot recently and it's S35vn seems to last longer than the exclusive as well.
 
The 710-1 and 710-2 came from a period when BM really had M390 dialed in. Something seems to have changed.
 
I wonder if they're having the same issue they had the first time -- inconsistent lots of steel coming from the company.
 
Minor update: I just got my 558 mini ritter back from Benchmade. Got in on the absolute first wave of them, had some possible issues with edge retention, sent it in for a new blade a couple weeks ago. The new blade doesn't appear to be shorter than the S30v models, a la the early production runs that were ~1/16th shorter. Haven't had a chance to test edge retention, but I'll post an update here once I do.
 
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I'd love to see some HRc numbers.

I would too.I bet the newer run is softer.I wonder if that was for better toughness? I have a 710-1401.I would like to know how it will perform.
If the softer treat ends up with maximum stainlessness I won't mind if edge holding is better than 154CM.

I prize stainlessness.But butter soft is a FAIL.
 
If the M390 is a Gen3 powdered steel how could it be inconsistent? According to BU, the process is basically fool proof and much more complex and refined than the standard stuff that CTS steels and all the CPM steel technology. Would BU allow for a huge bad batch to leave their foundry like that? Repeatedly? I'd imagine the QC processes and controls are much different for the steel industry than a company that uses it for a finished product. Any official announcements about the bad batches of steel? Is any other company using M390 having the same issues? Bradford? Spyderco? ZT? Survive!?
 
If the M390 is a Gen3 powdered steel how could it be inconsistent? According to BU, the process is basically fool proof and much more complex and refined than the standard stuff that CTS steels and all the CPM steel technology. Would BU allow for a huge bad batch to leave their foundry like that? Repeatedly? I'd imagine the QC processes and controls are much different for the steel industry than a company that uses it for a finished product. Any official announcements about the bad batches of steel? Is any other company using M390 having the same issues? Bradford? Spyderco? ZT? Survive!?

I think it much more likely the heat treat was missed. I read somewhere about a maker missing his and it took him a few tries to dial it in.
Really hard M390 probably eats tooling...so if you could run it a bit softer it might cut machining costs.
 
M390 can be temperamental in heat treating from my discussions with makers, mainly due to it being a high alloy steel it requires some very precise oven temps etc but there remains some room for variance.

One maker I spoke to had two blades, exactly heat treated the same way (4 thermal couplings in his oven, cryo etc) and it came back with HRC differences of 2 points. He submitted the blades to Bohler for analysis but I have not followed up on what their conclusion might be.

Either way, M390 seems to go through a learning curve when any maker starts using it. I am sure BM will have it dialed in by now.
 
I hated the way my Ritter m390 cut until I went 15dps and now it's a monster, and holds an edge wonderfully!!
 
M390 can be temperamental in heat treating from my discussions with makers, mainly due to it being a high alloy steel it requires some very precise oven temps etc but there remains some room for variance.

One maker I spoke to had two blades, exactly heat treated the same way (4 thermal couplings in his oven, cryo etc) and it came back with HRC differences of 2 points. He submitted the blades to Bohler for analysis but I have not followed up on what their conclusion might be.

Either way, M390 seems to go through a learning curve when any maker starts using it. I am sure BM will have it dialed in by now.

Glad to hear this. We have had some unhappy customers with M390 with none of them being Benchmades. I have had limited experience with it but have not been overly impressed!
 
Glad to hear this. We have had some unhappy customers with M390 with none of them being Benchmades. I have had limited experience with it but have not been overly impressed!

CPM S30V was plagued with similar issues, chipping, irregular heat treat response, unhappy costumers etc, when it was introduced. Now it is a stable part of every knife enthusiast diet.

There is a learning curve to everything IMO.

One important thing to note is that Elmax and M390 (or as per Bohler Stainless Powder Steels) come in 304 stainless can on the surface to protect the steel surface from oxidation during the forging, rolling and subsequent soft annealing processes. Some makers have expressed their concern with this as many do post heat treat grinding and the can affected their heat treatment results. They needed to machine the can off before heat treatment etc.

If you are interested I can send you the link on the discussion where Uddeholm chimed in.
 
CPM S30V was plagued with similar issues, chipping, irregular heat treat response, unhappy costumers etc, when it was introduced. Now it is a stable part of every knife enthusiast diet.

There is a learning curve to everything IMO.

One important thing to note is that Elmax and M390 (or as per Bohler Stainless Powder Steels) come in 304 stainless can on the surface to protect the steel surface from oxidation during the forging, rolling and subsequent soft annealing processes. Some makers have expressed their concern with this as many do post heat treat grinding and the can affected their heat treatment results. They needed to machine the can off before heat treatment etc.

If you are interested I can send you the link on the discussion where Uddeholm chimed in.

That would be awesome. You can email it to me at scott@usamadeblade.com
 
According to BU, the process is basically fool proof and much more complex and refined than the standard stuff that CTS steels and all the CPM steel technology.

The 2nd generation/3rd generation thing has been floating around the internet for some time now. Although there have been several "generations" of PM technology, they all use their own proprietary production methods, variations on the "generations." They may be similar, but they are not exactly the same, thus they cannot be directly compared. I see over and over, repeated many times in a number of forums, where someone says that company X uses 2nd generation, while company Y uses third generation, implying that company Y's product is superior since it uses a newer, better production method. But this is simply not true, since the specific production methods yield very comparable results. Compare M390 and CTS-204P, for example. If you had two knives in these steels that were geometrically identical (same edge thickness, edge angle, primary grind angle, blade stock thickness), same edge finish and had the same heat treat, you would not be able to tell these two steels apart, despite one being so-called 2nd generation and the other 3rd.

The bottom line is that Bohler uses an improvement on their 2nd generation and calls it the 3rd generation. Carpenter uses an improvement on the "2nd generation" and calls it Micro Melt. Crucible uses ??? and calls it Crucible Particle Metallurgy. I assume it to be their own variation on the "2nd generation."

A post that N. Brian Huegel made on the Spyderco forum is useful (in M390 Mule thread June 2011 - note that Crucible is not discussed here, they use their own proprietary variation):

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"As part of my interest in understanding powder metallurgy, I sent an email to Ronald Long at Carpenter Technology Corporation. He is the Commercial Manager of the Knife Blade Products division. He has graciously allowed me to share it with the forum. Here is a portion of our correspondence.

Q: Per this Spyderco forum thread, in what began as a discussion about their latest Mule made with Böhler M390, I have attempted to compare / contrast with your CTS-204P. As part of the discussion, it has been brought up that your powder metallurgy is 2nd generation whereas Böhler’s is 3rd generation.

A: From one of Carpenter’s R & D managers: “The first generation powder product that was originally produced in Sweden by Erasteel and Anval (now CPP AB) consisted of air induction melting in a top pouring furnace followed by pouring the molten metal into a tundish from which the molten metal is bottom poured out of the tundish and is atomized to produce a coarse powder, typically -1000 microns or -500 microns.

The second generation powder product as practiced by Erasteel, CPP AB, and Böhler, consists of the first generation air induction melting process followed by pouring the molten metal into a heated, refining tundish called an “ESH” tundish (Electro-Slag Heated tundish), where the molten metal is heated with graphite electrodes (Erasteel and Böhler process) or a plasma torch (CPP AB). The refining tundish permits the molten metal to be purified (reduce the amount of inclusions). After refining, the molten metal is poured out of the bottom of the tundish and is atomized to produce a coarse powder, typically -1000 microns or -500 microns (the same powder size as the first generation process).

Böhler’s third generation powder product consists of the second generation process followed by a modified atomization process that produces a finer powder, typically 250 microns. Böhler claims the finer powder reduces the presence of coarse carbides compared to the first and second generation, coarser powder.

As noted above, CPP AB uses the second generation powder process. CPP BVL (BVL is our facility in the US and our source for CTS 204P) uses both air induction melting and vacuum induction melting coupled with the use of reticulated refractory filters in its tundish to produce 150 micron powder (finer than Böhler’s powder) for P/M tool steel millform products. CPP BVL’s powder manufacturing process does not directly compare to the European classification system of “first, second and third” generation powder processing. BVL’s vacuum induction melting + filtration process plus the use of -150 micron powder is cleaner than the third generation process. The air induction melting process + filtration process plus the use of -150 micron powder is equivalent to the second generation process with a finer powder than the second generation process.”

From Ron: As you can see it is not exactly an “apples to apples” comparison when one puts the processes side by side.

Effectively, from dimensional perspective, our “2nd generation” process produces a finer, 150 micron powder than their “3rd generation” process which is 250 microns. And I don’t believe they would argue that their 250 micron material would have finer carbides than our 150 micron material.

The other issue is product cleanliness. I have asked for information on product rejection rates for inclusions and have yet to find an example. I am not saying they do not happen; just that folks are having problems finding the last time it did happen. In my short tenure here I have not dealt with an inclusion. I will look to get you a better definition of cleanliness relative to our product.

Regards,

Ronald Long
Carpenter Technology Corporation
Commercial Manager- Knife Blade Products
His only concern in allowing me to quote him and Carpenter is that he does not want to get into a situation where he might sound like, or be accused of, being critical of Böhler-Uddeholm which was not his intent. I do not believe that this will be the perception and I sincerely appreciate his explanation and knowledge on the subject. I also invited him to participate directly with this forum and also encouraged him and Carpenter to consider establishing a forum or sub-forum of their own. Time will tell if this comes to fruition, however, I do believe that the above is a definitive expression of Carpenter Technology’s deep commitment to our industry and the future of cutlery steels.
 
I bought one recently, and the blade cuts ok. It behaves more like 154CM than M390. The AFCK in M390 I have works perfectly. Strange how they had it down, then lost their mojo somewhere along the line.
My Ritter Grip with m390 doesn t seem to hold its edge as well as I would expect. Ahhh Benchmade.
Several other BM problems in the last year.
 
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