Thread: Chisel sharpness testing

This is completely nuts! Soooo interesting!

Those who love in-detail reviews that push hard to get The Real Facts will love this video.

Here is all the data as a spreadsheet: The chisel test - Google Sheets

and the "winner" was Narex Richter. Here is a video of them being made:

last year, I did a long iron durability test. The point was several things, but among them, to find out if LV's durability claim measured up (2 times typical other irons for V11).

I found out that in clean wood, their claim is accurate. There was a great amount of work. I planed somewhere around 40-50k feet of wood total and weighed the shavings, etc. I took microscope pictures of the edges - metallurgical scope....

(Freshly sharpened)
https://i.imgur.com/x6Z0gbz.jpg

(fully worn/dull)
https://i.imgur.com/NEa8MHe.jpg

What I have to say after doing it all and going back to woodworking is that I proved a lot of things I didn't perceive correctly about wear. AT first, because v11 did so well, i made a whole bunch of irons of the same steel and used them.

And now I'm back to using one for smoothing and one in a jointer for light work, but back to the old planes because the design of the planes makes them better/more efficient for work.

My point being - the testing shows what the testing shows. In my case, I showed that the best O1 iron that I can make is only about half as durable as the best particle stainless (same steel as V11) in clean wood. but the best O1 iron that I can make is *really* good (it's about as good as hock or slightly better - the made iron with the same steel as LV is about the same as LV's V11 iron in durability testing - no real savings in buying the stock and making, either).

I'd say any of the top half of the chisels in these tests will work about the same in context. I've got experience with sorby chisels, enough to know that they're softer and the spec in this test that's really going to divide people between good enough and not is hardness over 60 or 61 or so.

Certainly not trying to be obtuse here D.W. but am I correct in interpreting that you feel the ergonomics of a given plane can be preferable to another in hard use application (despite the latter having a low wear blade)? Or, that an initially sharper O1 /plane has something beyond the numbers?

Have you tried a blade of AEB-L steel?

I struggle with the various properties of steels and conjecture that the edge stability/wear situation of a plane is remote from chisel application unless perhaps comparing low angle planes to paring.

Originally Posted by Stocker

Certainly not trying to be obtuse here D.W. but am I correct in interpreting that you feel the ergonomics of a given plane can be preferable to another in hard use application (despite the latter having a low wear blade)? Or, that an initially sharper O1 /plane has something beyond the numbers?

Have you tried a blade of AEB-L steel?

I struggle with the various properties of steels and conjecture that the edge stability/wear situation of a plane is remote from chisel application unless perhaps comparing low angle planes to paring.

I haven't tried AEB-L, but would suspect that it's a great knife blade steel and would come up a little short compared to V11 in woodworking (especially in planes) as V11 has quite a bit more carbon and probably more chromium.

But back to the statements about edges and what counts. What I did find in clean wood with 1 micron diamond sharpening was:
* nothing really caused any of the edges to fail unless it was something severe enough (silica inclusions/bark inclusions) to cause all of the blades to fail
* the most abrasive resistant irons really do wear longer - in metal, abrasion resistance and really hard carbides and high tempering temps lead to long wear, but in woodworking, it's a little less clear. V11 is mostly chromium aside from carbon, a little bit of vanadium and some other things - chromium and a little bit of vandium with a really high carbon content is what sticks out though. One may expect it to be subpar compared to vanadium, but something really tough like M4 and V11 come out close together in clean wood

What I found in continued use so far, though, is that perhaps it's still not better for me to use V11 in my roughing planes. I think it takes damage a little bit more easily than O1 and the excellent wear resistance doesn't really matter if an edge gets damaged. Even little damage causes things to go downhill fast. Pile on to that the fact that the friction from a wooden plane is about 1/3rd that of a metal plane and you can spend more of your energy in rough work separating the wood from itself rather than heating the sole of the plane.

This is hard to communicate unless someone else has been at the same thing for a while - the fact that you know the iron in one plane technically lasts much longer in clean wood, but at the same time, you can't make that fact overcome the combination of use in less than ideal conditions and application by the plane design itself.

I just cannot get the same productivity out of any metal plane that I can out of a wooden try plane in heavier work, for example, even though I did the wear test on both types of irons and found in clean smoothing (where nothing really threatens an edge). V11 lasted well more than twice as long as my favorite ward irons (which are plainer than O1), but I can do a greater volume of rough work with the try plane than I can with any metal plane with the V11 irons in them.

While nothing threatens an edge in very clean already planed wood, I seem to be forever chasing little nicks in V11 or it's likeness of my own make on smoothing planes that see less than ideal situation. It could be simply due to:
* the v11 irons being in the cut twice as long, so they should take twice the damage
* the medium honing of v11 occurs on an abrasive at about 1/2 the speed (metal removal) of O1.

Does that make keeping nicks out of the iron a factor of four easier for O1? I don't know.

none of them will fail to get work done or create working past bedtime due to their shortcomings vs each other.

I think I'm in the same territory as you, D.W., if not in the same backyard. For years I chased "hard & tough" in plane blades after first encountering the HSS blades made by Stanley Australia (no idea which HSS they used), back in the mid 70s. The HSS blade was a revelation, especially so in our hard woods, it lasted twice as long as the original blades and seemed no harder to sharpen on the oilstones I then used. After that, I've used a succession of other "hard" blades like cryogenically treated M2, A2, and (finally) PM-V11. For planing Gidgee or the like, PM-V11 has no peer - some pieces of Gidgee can take the edge off regular blades in half a dozen swipes (literally, I'm not exaggerating), but the PM blade will keep on cutting cleanly for many minutes before I can feel any deterioration.

All good, so why am I content to still have mostly O1 or similar blades in most of my planes, particularly my 'best' smoother? The answer is that I've long-since discovered that with 'decent' woods, i.e., the type I select for most cabinetry jobs, O1 gives adequate longevity and is much easier to sharpen to a very fine edge. I spend more time working with a really sharp O1 blade than any of the others. Part of the problem, I've hypothesised, is because with PM blades especially, the edge fails more slowly, and so you spend longer using a sub-optimal edge before frustration drives you to stop & sharpen. I liken it to carbide-tipped circular saws where I wonder why the wood is becoming so hard to push through the saw until I realise I'm working with a very dull blade. In the good old days (when many things weren't so good), steel blades went downhill very quickly, so you stopped and sharpened or changed to a fresh blade much sooner, before the smoke-signals insisted you had to.

It must be a failing on my part, but I cannot sharpen PM blades to the same quality of edge I can put on O1 without spending at least twice as long at the stones, consequently I subconsciously (& consciously) put off sharpening them until they are just too dull to tolerate. I see claims that PM is "no harder than to sharpen than other steels", which is probably true compared with A2, since that's also a beast of a metal to put a truly fine edge on (which it loses at the first hint of silica, which many of our woods have in spades!), but certainly not so for O1 in my hands.

So my philosophy has changed to worrying far less about steels and just being prepared to maintain sharpness. It isn't half the chore I used to think it was, especially if I stop & touch-up often (so easy with chisels). The result is far more time spent using a tool that's a pleasure to use rather than fighting it....

Cheers,

It's possible to get the same sharpness on V11, but the fact that it abrades half as fast is very real. The ease of sharpening is a two parter:
1) it doesn't sharpen as fast as something like O1 at similar hardness. It sharpens half as fast. Kees Heiden actually abraded it because Bill Tindall over here didn't believe that it could be as durable as its claims (i believe bill's issue was that other higher vanadium steels seemingly tested about the same and he didn't believe it would do as well without the vanadium - it's super heavy in chromium, which turns out to be why it does well in wood).
2) though it doesn't sharpen as fast, it seemingly will sharpen as fine, but rule #1 has to be heeded. The fineness perception is what it will take off of the stones, and how easily it will dump its wire edge. it dumps the wire edge pretty well.

When I tested irons, I noticed something - the tendency (because of longer experience now) to really feel like another 20-25% more sharpening felt like "a lot more", but V11 needs about double. When I started counting strokes on V11 and CPM 3V, it became a real drag to actually sharpen twice as many strokes.

My test was idealized. V11 lasted twice as long as O1, the fine sharpening didn't really take any longer (i finish with a tiny fine bevel after removing everything else with a shallower bevel - it's the penultimate step and the grinding where things are really slower. If the final bevel is a bit smaller due to slower honing, it's no big deal), but the whole process did take a lot longer. If I cut it short, I didn't remove all of the wear.

In a less idealized situation (rough lumber, etc, knots), I believe the O1 steel takes slightly less damage, wears faster, and then wears more evenly around the damage - but the PM steels do pretty well at this. The issue is damage, though - if damage and nicking brings us back to the stones and it's equal depth as O1, then it takes twice as long to get out. Realistically in daily use, I have a clean iron edge less than I did with O1 (though V11 will leave a brighter surface and plane with less friction - an odd finding).

And, like you say, there's a feel thing that's gone when we're using a "i'm not sure how sharp it still is, but I guess it's still working" iron. In my ideal test, V11 lives up to its claims, but what does it equate to exactly when the situation isn't ideal? I don't know. I guess it's a little better, but attention has to be paid to the coarse sharpening work or everyone will be working with partially sharpened irons (which already happens with A2 and other highly alloyed irons - often.)

I've been fiddling with a tiny roundover on chisels, which get back to the stones due more to damage than wear vs. plane irons. It makes inferior chisels perform really well and there's less cut resistance vs. a flat bevel. Maybe I will post it elsehwere. It makes any chisel last longer in challenging use without increasing cut resistance (I see less cut resistance).

(fast complete sharpening is still the most important thing with hand tools as far as I can see - I'd put the double iron with it for anyone who dimensions mostly by hand, but suspect that there aren't really that many people doing that).

I ran through nearly the same thing. I got an HSS iron, then made my own for all my planes by braising CPM3V tips onto cheap bodies. I ran them like that for ~5 years or so, then switched back to Hock or Stanley irons. Like so many folks, I ended up running half-dull edges that simply went forever. Ironically, the giant leap in performance with conventional irons came from a stiff Hock chip breaker, not the iron.

For bulk stock removal, I simply made up a "Toothed" iron by grinding slots into a cheap hardware store Buck Brothers iron... You can hog off a lot of material real fast with those, then follow them up with a jack plane set for a reasonably deep cut.

Originally Posted by Stocker

Certainly not trying to be obtuse here D.W. but am I correct in interpreting that you feel the ergonomics of a given plane can be preferable to another in hard use application (despite the latter having a low wear blade)? Or, that an initially sharper O1 /plane has something beyond the numbers?

Have you tried a blade of AEB-L steel?

I struggle with the various properties of steels and conjecture that the edge stability/wear situation of a plane is remote from chisel application unless perhaps comparing low angle planes to paring.

OK...I have to admit I completely forgot about this. Larrin Thomas (a metallurgist here in the states popular with knife folks) suggested that if I wanted something that grinds easier than XHP/V11 and with as fine of carbides as possible, I should try AEB-L.

I have to apologize for writing it off, and here's why.
* It can be heat treated in the open atmosphere (but it's not that easy - it needs to be brought to about 1950 degrees F and kept around there for at least a couple of minutes to dissolve as much of the chromium as possible before quench- that means decarb and a slightly soft top layer, but that hones right off).
* I wrote it off the first time I saw the alloy because it's 0.67/0.68 carbon. That carbon level is crappy in plain steel - it hardens, but the durability at high hardness isn't good (it has toughness more than strength and we want to err on the side of strength to hold a fine edge and have just enough toughness not to experience failure in proper use)
* Larrin put together a superb page on AEB-L. I still wrote it off (he's not woodworking, and his test data is knife blanks slicing through silica impregnated cards on a standardized machine). I also figured that I might not be able to get it "right". Wrote it off is to be taken lightly here, though. I bought some stock to make knives figuring that I'd at least like some easy sharpening stainless knives that have decent strenght

Haven't made a knife yet.

I did a quick heat to high heat (which you can do with XHP/V11) and quenched. The iron that made was too soft and not fine grained. I forgot when doing this that with XHP, you're dealing with a PM - there's maybe not a real need to soak and dissolve carbides as they're already small. I mentioned my failure to larrin and he more or less said, you didn't dissolve any carbides, so I brought it up to temp in open atmosphere to bright orange (about where I've had luck with XHP) and held it there for a while. This would be easy in a furnace and a full 10 minutes could be done to dissolve absolutely everything.

I quenched in oil to try to make up for any shortcoming in temps and the fact that I have no cryo setup (oil quench of an air hardening steel can cause some warping, but it sometimes results in a point or so higher hardness, which makes up for the lack of cryo - sort of - it gets to the same hardness in different ways).

Bingo. The outside of the iron was soft (I saw no carbon pooling when heating, so I was surprised that it would still be that soft). I wrote it off again, sort of, but after three sharpenings I got through the soft layer into the hard stuff and now it's harder than I'd pick.

I was also testing 52100 against O1, and 1095 and 1084. So I did them and added AEB-L to the edge durability test. I think it's a good option. It's CHEAP, too. As cheap as plain carbon steels for bar stock (about $6-$8 US for enough stock to make an iron) and it's easy to work (like carbon steel) and sharpens on the same stones carbon steel does (V11/XHP does not across the board).

Footage planed from maple:
* 1084 - 997
* 1095 - 836 (toughness problems, but reading larrin's test data, this is just the case. I could temper the iron a bit softer but then it would be soft enough that it wouldn't outlast 1084 at higher hardness, which 1084 handles OK)
* O1 at about 63 hardness - 1231 feet
* 52100 at about the same hardness - 1235 feet (could be a point harder)
* AEB L - something over 2000 feet (2100 the first test, which caused me to rerun the test - at 1950, I stopped, but the iron was still cutting)

Larrin's data suggests that AEB-L should wear around 25% more than 52100, but my iron goes past that. Some of that could be due to the high hardness of the AEB-L iron (I'm gradually tempering it back to get it to be easy to sharpen on oilstones - it'll lose some wear resistance, but not much).

based on ratios with LN A2 and XHP/V11 previously measured, I would estimate the footage planed for both in the same above piece of wood to be as follows:
* A2 - 1540 feet
* V11 - 2460 feet

(when I tested irons in beech, I found A2 and V11 to be pretty consistent in ratio to the exact O1 iron measured above - maple can be hard to complete multiple tests in because it has inclusions in it that destroy irons, even in innocent looking dark spots that don't look or feel gritty).

I think the slickness and keenness of XHP feels a little bit higher, and I'm sure it wears a little longer than AEB-L, but if you want to make your own instead of buying from LV (no guarantee XHP and V11 are identical, but they are very close if they aren't), XHP stock is expensive, I only know of one supplier, and it's fairly hard on files and will air harden super easily even sawing it with a power bandsaw or drilling it - you have to go slow. AEB-L will also air harden, but not nearly as easily and I didn't notice it to do it in grinding or filing or drilling, at least to any extent that it challenged my regular garage woodworker tooling.

I have hardened and tempered a lot of plane irons, have a reliable setup even though I'm working mostly by eye, and good touch. I don't think the average person would have luck with AEB-L as easily as they would with 01 and 1084 (both of those are pretty easy, O1 especially because it's alloyed to fully harden through and through without having to buy special oils - veggie oil does just fine. 52100/1095/1084 benefit from a faster oil like Parks 50, and that stuff is expensive and has a low smoke point and stinks - but I use it for them).

I hardened AEB-L in soy oil, which still flows well here and doesn't make much smoke or stink.

I haven't made any chisels out of AEB-L and have no stock to do it, so this is more about plane irons and less about chisels as mentioned above. The best steel I've found so far for solid steel chisels is that in older files (like vintage heller files in the US, or older nicholsons - heller is kind of nice as the files are a bit thicker than nicholsons). I think file steel is probably 1.1-1.2% carbon with some additives to improve hardenability without making the grain much more coarse. File steel attains really high hardness in a parks quench (really high) and retains more of it through normal tempering cycles. In regular use, the very tip of a plane iron is more likely to have toughness problems than the tip of a chisel (but beginners will test chisel toughness before they understand that straight in is really the only way a chisel should go).

Standardized tests like the one by WBW above will always be won by the hardest chisel except where there are problems, like:
* an alloy that's not quite as tough as needed (V11 isn't a tough alloy, it's a high hardness stainless - few stainless alloys have significant toughness at high hardness, maybe none - AEB-L has high toughness off of high hardness, but not at high hardness)
* That leaves a question about the japanese chisel - the price shown for the matsumura chisel makes it look like it's a quality good, but it's just a mass produced chisel squished in a die, probably made of prelaminated material and just shaped after the squashing - you can tell by the shape of the hardened layer. If there was any significant power hammer work in a chisel like that from laminating a bit to the backing metal, the line wouldn't be so even). Used chisels directly from japan for about $15 each are generally higher quality - at 67 hardness, the matsumura chisel is overhard. If it had been 65, it would probably have won the test. At a couple of points above ideal, a chisel will have difficulty resisting chipping in even the lightest of work, or even when sharpening. If a chisel doesn't easily shave hair on both sides of the bevel and pare through a hardwood without showing lines on the work after a couple of pares, it's too hard (or too soft, but you'll be able to tell if a chisel is soft when you sharpen by the size of the burr).

Having missed the AEB-L comment above (or forgotten it) and run back into it, I sent LN an email with my results and suggested they look into it as an alternative both to O1 and A2. It has less wear resistance than V11 will, but users are far more likely to be able to stay ahead of nicking with regular honing (V11 sharpens easily, but it still wears half as fast on a stone even if the edge is crisp, and that makes it so that nicks accumulate and you have to make a conscious effort to do more middle and coarse work than you'd be used to -twice as much. That's a pain in some work - think planing glue joints, etc, let alone interrupted cuts on rough edges).

What I haven't tested yet with AEB-L is how far back I need to temper it for it to have good toughness in rough work as well as a fine planing test. As hard as my test iron is, I think it's just a bit chippy in anything other than downgrain planing. The edge can be buffed to mitigate that (as it can for anything) by rounding off the very apex and still have better edge life than A2 (this may be a good plan for V11, too, to prevent chipping), but at the hardness where my test iron is, there's room to temper back some (with the AEB-L) and still have good hardness, and the sharpening will just become sweeter and easier.

For anyone confused by strength vs. toughness in the above discussion:
* strength is how much force it takes to deform an edge
* toughness is how much deformation an edge will tolerate before it breaks

Strength is what allows an edge to be very fine, but there needs to be enough toughness for it not to break.

If you have a steel with high toughness (very high), it generally works better at lower hardness as the things that improve toughness usually decrease strength.

The reason japanese chisels have a reputation for feeling sharp is two parts:
1) they're hard, abrasives cut less deeply on them when same size abrasives are used
2) the hardness allows for strength - as long as they are OK with toughness no problem (but pushing the limits makes chisels that chip easily or break corners off due to lack of toughness. Japanese tool fanatics like to make claims like they're using carbon steel chisels above 66 hardness, but the reality is the edge life is shorter at hardnesses like that with white or blue steel than it would be at 64/65 hardness)

Originally Posted by IanW

I think I'm in the same territory as you, D.W., if not in the same backyard. For years I chased "hard & tough" in plane blades after first encountering the HSS blades made by Stanley Australia (no idea which HSS they used), back in the mid 70s. The HSS blade was a revelation, especially so in our hard woods, it lasted twice as long as the original blades and seemed no harder to sharpen on the oilstones I then used. After that, I've used a succession of other "hard" blades like cryogenically treated M2, A2, and (finally) PM-V11. For planing Gidgee or the like, PM-V11 has no peer - some pieces of Gidgee can take the edge off regular blades in half a dozen swipes (literally, I'm not exaggerating), but the PM blade will keep on cutting cleanly for many minutes before I can feel any deterioration.

All good, so why am I content to still have mostly O1 or similar blades in most of my planes, particularly my 'best' smoother? The answer is that I've long-since discovered that with 'decent' woods, i.e., the type I select for most cabinetry jobs, O1 gives adequate longevity and is much easier to sharpen to a very fine edge. I spend more time working with a really sharp O1 blade than any of the others. Part of the problem, I've hypothesised, is because with PM blades especially, the edge fails more slowly, and so you spend longer using a sub-optimal edge before frustration drives you to stop & sharpen. I liken it to carbide-tipped circular saws where I wonder why the wood is becoming so hard to push through the saw until I realise I'm working with a very dull blade. In the good old days (when many things weren't so good), steel blades went downhill very quickly, so you stopped and sharpened or changed to a fresh blade much sooner, before the smoke-signals insisted you had to.

It must be a failing on my part, but I cannot sharpen PM blades to the same quality of edge I can put on O1 without spending at least twice as long at the stones, consequently I subconsciously (& consciously) put off sharpening them until they are just too dull to tolerate. I see claims that PM is "no harder than to sharpen than other steels", which is probably true compared with A2, since that's also a beast of a metal to put a truly fine edge on (which it loses at the first hint of silica, which many of our woods have in spades!), but certainly not so for O1 in my hands.

So my philosophy has changed to worrying far less about steels and just being prepared to maintain sharpness. It isn't half the chore I used to think it was, especially if I stop & touch-up often (so easy with chisels). The result is far more time spent using a tool that's a pleasure to use rather than fighting it....

Cheers,

I agree with all of the above, but will add one thing:
* I think we often assume that planing super hard or contaminated woods with high hardness steels is based on toughness and abrasion resistance.
* I also think that I've figured out that what's lacking in the softer steels is edge strength rather than toughness, and that strength can be had by modifying the edge

I noticed in the couple of irons that really impressed me in difficult wood, what those irons really had was high hardness. The chinese brazed irons always performed a little better for me, but they say they're 61 hardness. When testing plane irons last year, we had one tested and the average of the three strikes was close to 66 (so much for their spec!!!). The alloy was very ordinary (just shy of being M2), but the hardness made it wear long even though it didn't wear that evenly.

Then, I fell into this unicorn business with chisels, and started using irons made of butter (softer irons love the buffer) that I never had much luck with because the apex would deflect, and they had an annoying wire edge (lower hardness increases toughness, so even in cheap steel, the wire edge forms easily and comes off cleanly not so easily). Those irons will nick on anything with a normal geometry. With the bevel buffed (which reduces clearance and clean wood edge life by about 20%), they planed cocbolo filled with visible silica with no edge damage at all.

This should be a !!!!!!!!!!!!!!!!!!!!!!!!!!!!

Those irons cost $2.99 and you can sharpen them just by looking at them and squinting. The buffer cannot form a wire edge, so that issue is gone. It also cannot keep a crisp apex, so that is gone. What i can do is make a rounded apex that is steep but very fine at the edge.

I hate to say it, but the $2.99 iron with modified geometry is better at cutting tough woods than any high priced iron I've ever bought. The toughest steel we know of here for practical use is CPM 3V. 3V can more or less deflect and be bent back to straight several times without chipping. But where it does that, the butter iron with the modified edge doesn't deflect in the first place. You can scratch the bevel and back of the iron with silica, literally, and still not have the edge chip or deflect. I noticed this on incannel gouges in rosewood, too- you can work thorough silica, see spider webbing/scratching on the outcannel and then dread what you'll see at the edge.....nothing. Even incomplete sharpening on the back of an iron which normally leads to failure next to the deep groves doesn't do anything (there's enough support around the deep scratch with the modified edge that it just stays as is).



This picture shows the edge of the butter iron at 32 degrees, and then modified (I'd have to check my notes - I think the damage on the left and the crappy broken up shaving occurred very early, like in 20 strokes on the test piece)

The modified edge shows the wear from the cocobolo - the silica can't dent the modified edge and skates off. Even the deep scratches lazily left to the edge (from a diamond hone) don't come apart.

This cocobolo (I'd have to reweigh to check) is the hardest cocobolo I've got (and most dense). It's not gidgee, but it's just under 1.1 times the density of water.

In this case, intentionally giving up some edge life results in far longer edge life because the practical and the theoretical line up.