(Take me to the short version)
You may be thinking a turning gouge is a hand tool. It is, but M2 is well known for being a good and potentially exceptional steel for making lathe tools. The reason for this is that it has an enormous wide double tempering range and can air cool. That is, it’s suitable for “hot work” at higher speeds where the edge of the tool can heat without being ruined. M2 has great potential for offering a good balance of edge fineness, sharpenability and edge life if the bar stock is well chosen, and hardened properly, generally to a high level. If you have underperforming M2 turning tools, they’re probably just lacking hardness – a chronic issue with mediocre tools that has varying reasons.
I turn almost everything with M2 tools, especially skews. You can touch them up on stones and then grind with abandon when you need to. As a hand tooler, I probably sharpen more often than most turners, but for example, if I am turning chisel handles out of something abrasive, I will spend some fraction of a minute re-establishing the apex on a large oval skew and then buff or polish off the burr. Let’s not get too far into that or we’ll end up with turners mentioning edge life and coarse finish and such – if you’re trying to get close to finish off of turning tools, you still need some polish.
So, where we see M2 much less commonly is woodworking tools. Academy saw works made a blade out of M2 that by pictures of wear at the edges and edge life must’ve been suitably hard. Some of the Chinese tools sold as HSS are M2, or close – an XRF analysis of some inexpensive high speed steel irons that work well shows perhaps some penny pinching on expensive alloying elements. In the case of the sample someone tested both for mine and their satisfaction of curiosity, we found the brazed irons to be harder than claimed (65.5 hardness average despite a claimed 61) and “almost” in M2 spec. Not a surprise – it’s probably the least expensive high speed steel.
What is it?
M2 high speed steel is a lower cost alternative to an early tungsten high speed steel. You can read about Mushet (which is before that), and then tungsten high speed steels if you google. Knife Steel Nerds is always an excellent start. Tungsten high speed steel is expensive. M2 ends up being common now because it was developed in the “ingot era”, if there was such a thing, before you could make up for composition problems just by creating a zillion little powder ingot balls and melting them together. I’d imagine even with powder metallurgy, too much faffing in heat treatment quickly loses the even microstructure.
What’s the significance of ingot? Steel is generally ingot (cast into an ingot, bar, ball, block, whatever) and then worked by rolling or forming, or powder metal where the ingots are tiny balls, all the way down to a few microns or perhaps even a micron. And there are in-betweens like spray forming, which are a little less expensive and may suit operations that aren’t relevant to woodworking tools. Not to say it’s a good process – it can improve steels that have terrible toughness due to wandering large carbides when done in ingot type (D2 is one), but if it makes it possible to do other industrial processes that have nothing to do with tools, we don’t care.
Knowing that, the basic premise here is ingot type steels are cheaper to make and if the alloy is amenable and creates a fine microstructure without the expense of something like powder metallurgy, that’s our gain as users. The steel will cost less and won’t be as difficult or costly to cast and process. This should not be confused with the end product being less good. Powder metallurgy can add a lot of toughness and fineness to something that just would be terrible in ingot form. We just don’t necessarily need 15% vanadium in woodworking tools, or enormous volumes of chromium carbides, like we see in V11 (analysis says “PM-V11” is just CTS-XHP). I think XHP is an interesting steel, but it fills a marketing need more than a user need. The rarity of it outside of Veritas has to do with a combination of attributes that make it pleasant, but not ideal for use. It’s a good case of a steel that’s not really any better than M2 for hand tool use, and it’s incapable of high speed use. It’s similar to D2 with more chromium and more carbon – so if ingot D2 looks coarse vs. powder D2 in micrographs on knife steel nerds, imagine what XHP/V11 would look like with more alloying elements. It doesn’t exist in marketed ingot form.
So, hopefully we’ve established some understanding here that it isn’t a surprise that pre-PM steels that were formulated to do well in ingot form aren’t “worse than PM steels” just because they’re not powder metallurgy, and it’s absolutely not the case that “PM steels are finer grained”, because they are generally finer carbide structure only against their ingot equivalents, which sometimes don’t exist. It also shouldn’t be much of a surprise that people actually knew what they were doing at the time and designed steels that wouldn’t be like D2 or 154CM with giant carbides.
That brings us back to M2 – the recipe for a steel that is good in ingot form is getting the balance of elements right to form useful carbides, but not large crack propagating poorly dispersed versions of them. Or in the case of very fine steel (like AEB-L), reducing carbon among the alloying elements to prevent the ability for large carbides to even form. AEB-L is a tangent, but it’s a superb example of creating a finer microstructure steel than any popular PM that I’m aware of. So summarizing this lengthy discussion about ingot and making the point here, M2 is a lower cost steel than the tungsten-alloy high speed steels that preceded it. I have no experience with those to compare them to M2, either. But with the low cost comes no real compromises unless you are a person who feels like you need more carbide volume to do day to day work (you don’t, but you can feel that way).
An interesting comparison here with M2 are Larrin Thomas’s micrographs – of M2 vs. conventional D2 vs XHP (V11). These are all from this fabulous page put together by Larrin Thomas – a legitimate expert who tries to get and give the right answer:
You can see in the micrographs – and if the individual picture links become dead at some point, the main link will allow you to just do a “find” in the page, that M2 is lower carbide volume than V11, much higher than O1, and in the balance of things, the groups of carbides are no bigger than the groups of carbides in V11. The carbides (imparting wear resistance) are lower volume, but of different types. To put the effect plainly, at similar hardness, M2 lasts slightly less long than V11 (80-85% as long in my ideal scenario testing), but does well in proportion to the carbide volume. This is because some of the carbides are harder in M2 than the type that dominates V11 (chromium), which happens to be the same type that dominates A2 and D2 – chromium. For slow work, i would refer to chromium as the woodworkers carbide because it seems to be OK in a whole bunch of volumes, as long as the higher volumes are powder metallurgy, and it’s not harder than common sharpening stones.
I haven’t found 10V in limited testing to have the same sweetness in the cut as chromium carbides can have, but jumping around here – 10V being similar sounding to V11 and entirely different – 10V is primarily vanadium carbide, and much longer wearing than V11, and capable of high speed work, thus you’re not unlikely to find it in higher end turning tools. V11 (XHP) would lose its temper in high speed work, and won’t be found there, and 10V will be much more expensive than M2.
This whole idea of talking about carbides in steel probably merits a separate discussion. Nobody would read it – summarize here to say, that it may seem I’m contradicting myself because I don’t care for A2, D2 or V11 (of those, I’d choose V11), but I care even less in woodworking for steels that are primarily vanadium carbide – they can wear a long time but they don’t have the same cutting sweetness as A2, powder D2 (not conventional) or V11/XHP. I just don’t like any of those three nearly as much as more plain ingot steels that do not have an imbalance of wear and edge strength leading to accumulating damage that doesn’t get removed by most people when sharpening.
Phew – I’ll bet a comment about M2 that’s a bit more plain and bold is in order here, as I’m comparing it to a lot of other steels out of something that has me with unanswered questions based on the above. M2 is inexpensive, it’s as tough as V11, it can be tempered as hard or harder, and wear just as long meaningfully (in theory less, but good luck doing regular work and getting to the footage V11 can plane without accumulating a bunch of edge nicks) as V11, it makes a wonderful chisel, and unlike V11, it can be ground with a heavy hand. You are more likely with M2 to burn your fingertips than you are to ever threaten the steel, and even if you grind it to a dull red, just let the steel air cool and hone it and move on. That’s the point of high speed steel. It would seem that someone could offer M2 plane irons and chisels at a slightly higher price than A2, do them well at relatively high hardness and sell them. And people would like them. But so far, we’ve had the academy saw works blades sold making spurious claims (in reality, their edge life is a little less than double good O1) and at a really high cost.
The other alternative is the $10 Chinese brazed blades on aliexpress and other places that are “almost” M2. They can be excellent -and some can arrive extremely hard with flatness issues that the average person can’t handle even in more agreeable steels, and my testing of one of the Chinese irons showed that it outlasted A2 by a lot, but the carbide dispersion did not live up to the fineness of the good quality done in the micrograph above for M2. Who can really criticize when you have an iron made and shipped to you from china for less than the cost of the steel in most of the boutique stuff. I can’t, they’re great for the money, but the idea of buying one and it’ll be perfect – not practical.
And with that, I really don’t get it. I don’t get why someone doesn’t make high hardness good quality M2 plane irons and chisels off the rack in the US. The lazy answer is A2 is easy for everyone to use. It’s generic corn flakes for someone who has to feed church breakfast – not cheaper than pancakes – but cheap enough and really easy to prepare industrially. And everyone, for a while, bought into “we have it because it lasts longer”. I doubt that’s the reason. We have it because doing steels a little bit more plain at high hardness is pretty difficult industrially.
I have a set of cheap Chinese chisels that are shaped like triangles – they’re blanked from what I can tell (just punched right out of bar stock), the design is terrible, but the steel is wonderful. The hardness is high and the chisels still sharpen reasonably on regular stuff, can be ground quickly with a heavy hand when needed, and the only thing missing is small modifications that would make them hold up and a savvy marketer. The reason they fail is an interesting one – the chisels are blanked in a cross shape with a tiny short tang. the “T’ of the lowercase T shape acts as the bolster and the “top of the lowercase T” is a tiny short tang that hogs out the end of the handle quickly and the handle falls off. Great steel, with a slight shape change, would be a difficult chisel to beat. these are different than the chisels you see with a braze/bronze line across the middle – no experience with those. Probably from the same company, though (woodwell, mujingfang).
The Composition and Summary
Once you understand alloying, the composition may make more sense. You can discern things from it. M2 has some range, so I am just going to provide straw numbers instead of ranges, what a typical version could be.
Carbon: 0.9%
Chromium: 4%
Vanadium: 2%
Molybdenum: 5%
Tungsten: 6%
And perhaps some traces of other things, with some listings claiming cobalt and others not. Cobalt adds hot hardness at the expense of toughness in a steel where we probably don’t want to give it up. It may be more useful in drill bits where the end of the cutter lives a horrible life in the first place – pressure, heat, abuse.
Vanadium is in M2 in great enough numbers to make carbides, but not that much and it sharpens fine on stones that don’t cut vanadium carbides. “regular stones”. And Tungsten is there, after I mentioned that it has mostly replaced T1 (tungsten) high speed steel when cost is an issue. T1 has 18% tungsten, so it’s not the exclusion of tungsten that makes M2 less, it’s just much less of it.
In discussing what each typically does – vanadium creates carbides but also prevents grain growth in heat treatment. The same is true for chromium. Molybdenum and Tungsten both create hard carbides with literature that I’ve been able to find suggesting that the performance of molybdenum carbides is similar to tungsten carbides. Which points back to -similar function, lower cost, of course that will be favorable when cost counts.
Typical high quality temper hardness: 64 on the C scale.
Breaking toughness, which is a little hard to use directly for woodworking purposes (we don’t hit tools in the middle with a hammer and see how hard they are to break) is about the same as V11 and O1, and with higher hardness and good microstructure, edge stability in my experience is very good (better than V11, probably due to lower carbide volume).
What’s a Good hardness for Woodworking?
For just about everything with abrasion resistance, a case can be made that higher hardness is better to avoid damage due to deflection. Higher hardness also improves wear resistance in ideal testing that doesn’t damage edges. I’ve had Chinese irons of other designs that were HSS but a bit soft. I see no virtue in them because they will dent, nick or roll too easily and the point of long life makes no sense. 64 that’s mentioned as a typical result on metallurgical pages for M2 is, in my opinion, probably ideal.
Except, good luck finding it. If you come across an academy saw works blade and you’re looking for long planing intervals, if V11 costs $50 or whatever it is, I think one can’t make a case for spending double the amount for an iron that’s not functionally better, but just as good. Unless you really love grinding steel with a really heavy hand and like the heat tolerance.
I wish someone would buy high quality bar stock and offer at least plane irons in M2 at the 64 target, but there are a lot of people trying to blank or cut and heat treat irons in small volume (DFM toolworks for example) and success at this point has to do with implied friendship from boutique makers (a little one sided as you’re friends if you’re buying! they’re not buying anything from you) and marketing and getting gurus to run around touting your stuff.
One of those gurus will gaslight you – for example, telling people that V11 and 10V are the same thing or similar (they’re not close), that a tool maker who sells 10V isn’t using it because they don’t know what they’re using (they’re using 10V – managed to gaslight even one of the manufacturers) and then if you correct them, tell you that everyone is confused by talk about steels so don’t do it. But, that’s the world of gurus and influencers, I guess. Information is a reason to buy when they’re offering information. When it’s pointed out to be wrong, it’s written off as “too confusing and not important to discuss further”.
As you can probably tell, I have a distaste for people who don’t address what’s being discussed, but create other hurdles. The folks who alternate between “expert” (rarely are, or are too ready to make bold claims outside of things they know) and gaslighting are similar to someone running into a hurdle race and placing hurdles that aren’t supposed to be there, alternating between removing them vs. lifting them higher to see if they can block you. We all end up wasting our time.
I would imagine if you asked why there aren’t more woodworking tools made of M2 in good quality for “cold work” (planing, chiseling), you’d get a myriad of answers and most would say something about it not being as good as _____ or being coarse grained. I’ve seen these in drive by posts -“you can’t sharpen it. it’s meant to be sharpened on a grinder wheel!”, and so on. The real answer here is it would make fine tools, but nobody’s had the inclination. And where there is no inclination, it’s generally because entering or expanding the market isn’t very likely.
After all, the point I’ve made elsewhere still stands. Will any of this stuff improve your productivity as a woodworker over plain steels? No. it doesn’t matter how hard or abrasive the steel is, the time involvement to sharpen plain steels is still in proportion with more abrasion resistant steels, and will overall end up being less due to the ability to keep sharpening ahead of edge damage. We’re all guilty (me included) of wanting to try the different new stuff, anyway.
Of Making by Hand with Wood and Steel 