M2 experience?

[Artfully Martial]

Just wondering how you guys felt about M2....thinking of picking up a 710.... I loved my D2 stuff, so compare it to that. Birthday tomorrow.

 

[yuzuha]

It is like D2 only finer grained so it will take a keener edge and lower sharpening angles. My 2nd favorite next to ZDP-189 if the Spyderco Cali. jr. is anything to go by.

 

[Nimravus Nut]

I just bought a nimravus in M2.. this stuff takes a scary edge and a whole lot tougher than 154cm. The only thing I didn't like about it is the edge has discolored after a little use. After all it is not stainless.

 

[tidefan]

I have a Nimravus in M2 and I love it. Scary sharp, holds that edge for a LONG time, and is fairly easy to sharpen on a diamond stone...at least for me it is. It's now my primary backpacking/camping fixed blade...jim

 

[Danbo]

Just don't let your M2 blades get too dull, as the stuff is NOT easy to sharpen if you do. I remember those little Gerber bird and trout knives(back when Gerber made good knives). Those little knives would cut and cut, but were almost impossible to sharpen, even with a diamond stone. I believe Benchmade is tempering their M2 blades a tad softer though(but, still very hard). M2 is some good steel.

 

[cmd]

I have been a fan of D2 for a long time but just recently got a 710HS, my first experience with M2. I'm still a fan of D2 but now I am a raving maniac for M2.

It sharpens easily with my sharpmaker, considering the relatively high hardness. It takes a highly polished convex edge with a little stropping. It holds that super-fine edge for a long time, and the edge comes right back with very little effort.

Every self respecting knife nut must have at least one M2 blade. You can do a search and all, but you really have to experience it for yourself.

Go get one!

 

[Blop]

Just wondering how you guys felt about M2....thinking of picking up a 710.... I loved my D2 stuff, so compare it to that. Birthday tomorrow.

I feel great about it as long as batoning isn´t the main task. By the charts it can take a lot more than other high alloyed steel grades but is a breaker instead of a bender. But it takes one of the best edges.

I am completely satisfied with my Nimravus in M2.

 

[DGG]

It is just another dumb old knife tool steel.

If it is heat treated properly and if the style and grind of the knife is done properly you will end up with a nice knife.

One of the best fixed blade outfits I know uses A2 (which is very similar I think) in their knives and sharpens them with convex edges which is unusual in the industry. It is Bark River Knives out of Michigan.

http://www.barkriverknives.com/

http://www.barkriverknives.com/huntsman.html



Here is a link that discusses all kinds of "2" steels used in knife making.

http://www.ajh-knives.com/metals.html



Here is what Benchmade says about their particular "2" steels. Note what they say about corrosion and what type of coating they use with M-2 steel.

http://www.benchmade.com/about_knives/our_blades.asp

 

[Cliff Stamp]

One of the best fixed blade outfits I know uses A2 (which is very similar I think)

M2 and A2 are not similar, M2 is a very high wear resistant high speed steel, A2 is a medium alloy air hardening steel.

-Cliff

 

[Stockman]

After owning a couple of 710HS for a few years, I am still surprised more knives aren't made with M2. It seems to keep a hair splitting edge longer than any stainless knife I own, including S30V, VG10 and 154CM. Saying this, I personally haven't really tried many carbon steels besides 1095, INFI and SR's 52100, but they have all been in larger fixed blades.

Both 710HS that I have purchased required a heck of a lot of reprofiling to get the primary cutting edge below 30 degrees inclusive, so if you want them to perform to the steels capability, be prepared for some serious work on the Sharpmaker. The slight recurve makes it a nightmare to profile on a bench stone - but then again, I'm no freehand pro.

 

[DGG]

M2 and A2 are not similar, M2 is a very high wear resistant high speed steel, A2 is a medium alloy air hardening steel.

-Cliff

Cliff, is there really that much difference in edge holding ability at the temperatures that knives are used at?

http://www.timken.com/products/spec...ch_info/PDF_Files/techtopics/Bulletin 107.pdf

They both seem to take a decent almost identical Rockwell hardness value.

Here is a Timkin chart but I'm not sure at what temperatures they are measuring the wear resistence or if temperature makes that large a difference.

http://www.timken.com/products/spec...ch_info/PDF_Files/techtopics/Bulletin 116.pdf

 

[cmd]

I don't get all of the warnings about M2 being hard to sharpen. For me it was actually easier than D2 - comparing a BM806D2 to a BM710HS on the same sharpmaker. Admittedly I did not have to reprofile mine, but I have sharpened it enought to get a good feel for how it behaves.

Now I will definitely go along with the advice that there tends to be a wide variation in the edge profiles that come from Benchmade and that a lot are 40 or more degrees inclusive and are sometimes uneven. I was very fortunate to find my 710HS done right on 30 degrees inclusive and evenly ground. I passed on several 710HS examples in the past.

Also, about M2 being "a breaker instead of a bender", my experience is that with some light prying on tree bark it has some nice lateral flex. I decided not to push it hard because I was nervous about the BK coating, but it certainly gave me a lot of confidence in the blade. I think Benchmade ran it at a lower RC than what Cliff would say is optimal in order to make it tough.

 

[WadeF]

They both seem to take a decent almost identical Rockwell hardness value.

Last I checked the hardness of steel isn't the only factor in determining how well it will hold an edge.

M2 is one of the few steels with Tungsten added which help to improve wear resistence.

It looks like M2 maybe not be as tough as some other steels, but for a 3-4" blade in a folder this shouldn't be a big deal since you shouldn't be using it to chop through logs, etc. In a small folder that will be doing things like cutting card board, opening envelopes, cutting rope, etc, I'd rather trade away toughness to have better wear resistence so it holds it's razor edge longer.

Some of the expert sharpeners around here have found M2 takes a very sharp edge and the blades can be re-profiled very thin.

It was my BM710 with M2 that I split a hair with 3 ways. That's splitting the hair in half, lengthwise, and then splitting one of the halves in half.

 

[Cliff Stamp]

Cliff, is there really that much difference in edge holding ability at the temperatures that knives are used at?

Good question, knives do get hot when cutting cardboard, do they get hot enough to effect the temper at the very edge, I don't know. I have done trials running knives on cardboard slow vs fast and the difference is very large, however this could just be due to more energetic impacts. I would like to see M2 vs O1 on cardboard slow and then fast and see if the difference is the same.

They both seem to take a decent almost identical Rockwell hardness value.

M2 is generally ran at 65/66 HRC in cutting tools, A2 at around 60, most knifemakers run M2 much softer like Benchmade for toughness and it actually has a torsional toughness peak at that hardness :

http://www.panix.com/~alvinj/graphM2.jpg

Though frankly I think it is more of a fluke than actual intentional design that this happened. In regards to wear resistance, even at 62 HRC which isn't it's maximum value, M2 is several times A2 :

http://www.crucibleservice.com/datash/dsA2v12.pdf?CFID=226619&CFTOKEN=34882801

A2 is more of a general work steel with decent toughness while M2 is a focused steel made to cut things, including other steels.

Also, about M2 being "a breaker instead of a bender" ...

When they first came out there were reports of it on rec.knives that the Benchmade M2 blades could be bent enough to not fit back in the handles and they would not break. You could probably ask on the Benchmade form about the set/break points.

-Cliff

 

[Artfully Martial]

So you'd recommend the 710 in HS over the regular?

 

[DGG]

Wade - how'd you hold it still enough to do that? Great picture!

I'm not and never will bash M2 or A2. Both are very good knife steels.

 

[M Wadel]

im waiting for m4.. http://www.crucibleservice.com/datash/dsM4v6b.pdf

 

[cmd]

So you'd recommend the 710 in HS over the regular?

I like it better that 154 by a long shot. Definitely worth the few extra dollars.

 

[Satrang]

M2 and M4 have been around for 60 years. Why is it that these steels have not been used more often for blades?

 

[Daniel Dorn]

Can't answer Satrang, but I wanted to address Cliff's statement:

M2 is a focused steel made to cut things, including other steels.

I've used the blade on my BM 730CFHS to take the dings, and roll-overs out of my other blades before. Just a few quick strokes down the side bevel, knife-steel style, and the other blade is back to normal.

I've also used the knife to cut gypsum board for a couple of hours, and a few minutes with ceramic, and it's back to my working sharpness.

I really need to find a 710HS, though.

Daniel