Problems sharpening/using PM-V11 blades

[Allen Jordan]

I own a couple PM-V11 steel blades for my Veritas planes and I can never seem to get them as sharp as I expect.

Even after several sharpening cycles, my shooting plane's stock PM-V11 blade has trouble slicing paper and isn't all that good at cutting the end grain of even cherry or pine. Shooting with my LA jack equipped with a 25 deg A2 blade does a far better job.

I also just sharpened up a brand new 50 deg PM-V11 blade for my LA jack, but despite looking shiny it feels dull to the touch, can't slice paper, and just bounces across straight-grained walnut when testing the cut. Here is what the blade looks like after sharpening:

http://i.imgur.com/rRFFZD4.jpg

Pretty shiny right? Looks exactly the same as my A2 blades after sharpening. But it doesn't catch my fingernail or the skin of my finger, can't slice paper in any direction, and just bounces off / skids over anything I try to plane. Couldn't make any shavings off my test block of walnut.

I sharpened the 25 deg A2 blade the exact same way, popped it in the plane, and the same piece of walnut now cuts perfectly:

http://i.imgur.com/gcpH5Lf.jpg

I use a variety of the Rob Cosman freehand sharpening technique, which starts on a 1000 grit diamond stone for the secondary bevel and then moves directly to a 15000 grit shapton pro waterstone for the tertiary bevel, followed by a couple strokes on the back to remove any burr and polish the flat. I also strop a few strokes on leather with white rouge, but it isn't necessary... my A2/O1 irons are sharp as hell after either way. When I sharpen PM-V11 this way, I can never feel a burr on the back after even the coarsest stone (unlike A2 and O1), and when done the edge just feels round to the touch... like I'd have to work hard to cut myself with it.

So what on earth is happening? This steel has been advertised as god's gift to hand planes, but it just feels like crud each time I use it. Is it a flaw in my sharpening technique? I'd really appreciate any advise on the subject.

[Mike Henderson]

I'd suggest contacting LV. The PM-V11 blades I have sharpen up very nicely.

Mike

[Allen Jordan]

Okay, I’ve been experimenting with this and tried sharpening the shooting plane’s iron for much longer on each stone. I spent maybe 30 sec to 1 minute on the diamond stone and was finally able to feel a burr on the back, the first time I’ve been able to do so on this steel. I then did about 30 seconds on my 15k stone and noticed a tiny wire burr peeling away from the cutting edge, like a super thin wire. So I kept at it and did another 30 seconds, then ruler-tricked the back.
And it is now sharp as hell, exactly the same as my equivalent A2 iron when cutting paper. I popped the now-sharpened PM-V11 blade into my jack (nice that the shooting and jack plane blades are interchangeable), and it works flawlessly. The shaving curled up tightly, but I stretched it out and took a picture:

http://i.imgur.com/D4ERVHR.jpg


This is amazing to me because I did the same thing when the blade first arrived… lots of time on each stone, but didn’t achieve anything like this edge.
So I have two theories. I could not be spending enough time on each stone to properly form and remove a burr. Or possibly they grind the edge thin before tempering the steel, making the steel too soft for the first few sharpenings… and now I’ve broken through to the properly hardened/tempered core.
I’m going to try sharpening the 50 degree blade again next. I’ll report my findings. Thanks for the help.

[Jim Koepke]

I use a variety of the Rob Cosman freehand sharpening technique

I am not at all familiar with this method.

I do know my one PM-V11 gave me a bit of trouble when it was new in my shop. It is a harder metal, the beauty of it is when it is sharp, it stays sharp longer than any of my other blades.

Whenever I have a problem with sharpening in my shop I stop and go back to the basics. Single bevel with nothing fancy until there is sharpness.

If your hands are not locked in position as the blade is going back and fourth, you are likely to get a rounded edge.

jtk

[Niels Cosman]

I only have experience with the PM-V11 chisels, which did not seem much different to sharpen than A2 and the edge holds up to plenty of chopping.
Shiny doesn't necessarily mean it's sharp. I wonder if your edge hasn't been dubbed perhaps from an errand swipe or from the back side when lifting it off your stones. I would reform the secondary bevel, making sure that you have raised a burr across the whole length of the blade.
I might consider adding some intermediary stones. Jumping from 1000 diamond to 15000 is a pretty huge leap and seems potentially problematic . I currently sharpen 1000/3000/10000 using Sigma Power II's, or 1000/4000/8000 using Nortons. I also use a honing jig, which I have found to be idiot proof (I test it everytime I use it :)).

[Allen Jordan]

I was able to get my 50 degree PM-V11 blade sharp finally. I again spent 30s - 1 minute on each stone and was able to feel the burr before removing it on the 15k. Looks like I just needed to spend about 2-4x more time than I do on A2/O1... this stuff is really wear-resistant. Here is a shaving I took with the blade on the same stubborn piece of walnut, against the grain:

http://i.imgur.com/Mi0Dnc7.jpg

It left a great surface and pushed without much resistance (other than from the high angle). So thanks for all the help, sorry I'm so inept. I'm glad I was able to work this out, as I just ordered a couple more planes from LV's cyber monday sale :) .

[Allen Jordan]

Bonus pic of my freshly sharpened shooter:

http://i.imgur.com/YAHc1bw.jpg

It cut that walnut real good.

[Derek Cohen]

I own a couple PM-V11 steel blades for my Veritas planes and I can never seem to get them as sharp as I expect.

Even after several sharpening cycles, my shooting plane's stock PM-V11 blade has trouble slicing paper and isn't all that good at cutting the end grain of even cherry or pine. Shooting with my LA jack equipped with a 25 deg A2 blade does a far better job.

I also just sharpened up a brand new 50 deg PM-V11 blade for my LA jack, but despite looking shiny it feels dull to the touch, can't slice paper, and just bounces across straight-grained walnut when testing the cut. Here is what the blade looks like after sharpening:

http://i.imgur.com/rRFFZD4.jpg

I spent maybe 30 sec to 1 minute on the diamond stone and was finally able to feel a burr on the back, the first time I’ve been able to do so on this steel. I then did about 30 seconds on my 15k stone and noticed a tiny wire burr peeling away from the cutting edge, like a super thin wire. So I kept at it and did another 30 seconds, then ruler-tricked the back.



Hi Allen

A couple of points:

The sharpening system (1000/15000) you have is inefficient on anything but a micro bevel. You will still get a blade sharp, but it will take a longer time to do so. By contrast, I hone the same blade with a fresh grind in roughly 20 seconds. And it is sharp enough to cleanly pare end grain radiata pine (horrible wood!).

It is not just the stones I use, but I do not ask a stone to do more than it is designed to do. You are asking your 15000 to do the work of a 5000 stone ... before it also does the work of a 15000 stone. That takes more time and effort. As an example (and not intended as a recommendation), I use Shapton Pro 1000, and Sigma 6000 and 13000.

Are you honing a micro bevel or a secondary bevel? It looks secondary (good), but the primary bevel looks very steep (bad). If the primary bevel is greater than 25 degrees, you cannot hone a camber efficiently. Your blades look straight across. Straight blades cannot take deep shavings and will leave tracks, even if the shavings are very thin. To efficiently create a camber on a BU plane blade, start with a 25 degree primary bevel, and then use a secondary bevel to add in the desired camber. The secondary bevel will add the necessary steepness to create the desired included angle.

Please read this article: http://www.inthewoodshop.com/WoodworkTechniques/TheSecretToCamberinBUPlaneBlades.html

Regards from Perth

Derek

[ken hatch]

Allen,

It is hard to diagnose a sharpening problem just from a photo and I know I'm late to the party but let me add a thought or two.

The first photo on the right end of the blade is a sliver of reflected light, if there is reflected light anywhere along the edge it is not sharp. You mentioned time a couple of times, that you sharpened for a time and/or number of strokes which make no never mind, what is important is what you noticed in reply #3 & #6, work on a stone until you can feel a small wire edge, go to the next stone remove that wire edge and raise another. repeat until you reach your finish stone. Work the finish stone to the point where the remaining scratch pattern is smooth to your eye and you can not see any reflected light and both back and bevel are smooth to touch. Polish does not make sharp, my sharpest longest lasting iron will have a slight haze. There is also little reason to test for sharp, if it looks sharp and feels sharp it is sharp.

I'm glad you worked out your problem.

ken

[Brian Holcombe]

Grind the primary bevel until the secondary bevel is nearly gone, or gone entirely, then restablish the secondary bevel and keep it very slim.

[george wilson]

I agree with Derek: You have a very blunt looking secondary bevel there,and you need to get at least one intermediate stone to go between the diamond stone and the final hone.

[Allen Jordan]

Derek, thanks for the feedback... I've been consulting a lot of your plane reviews lately so I really value your information. For my sharpening technique, I leave the factory bevel as the "primary bevel". I lift the edge slightly on the 1k stone to make a secondary bevel, going until I feel the burr, then lift the edge slightly more on the 15k to make a tertiary bevel. I also press harder on each corner for about 2 seconds on the 15k stone to make a very slight camber. Theoretically on each step I'm only removing the thin bit of steel right at the edge, so it doesn't need the in-between grits. I have to be careful not to increase the primary bevel too much while doing this. So far this technique has worked great for years on every O1 and A2 blade I've thrown at it, but I think I'm seeing its limitations with the very wear-resistant PM-V11. I have 5k and 8k stones I could use as intermediate steps, it's just hard to maintain angles when freehand sharpening over many stones... maybe I'll try out a Paul Sellers style rocking bevel.

The blade in the picture had a factory-ground 50 deg bevel. I ordered it long before I read your description of just honing a 50 degree bevel on a 25 deg blade... nowadays I would just order the 25. I may still grind it back to 25 degrees someday on my stationary sander. I've noticed that honing such a steep bevel freehand is difficult and prone to catches on the stones.

[Brian Holcombe]

That will work but the more often you repeat the process the more often you will cheat and raise the bevel further. That's the reasoning behind my advice, you reset the process every time, which will eliminate raising the bevel too far.

[Marty Schlosser]

Brian,

At the sake of sounding as though I'm disagreeing with you, I'll state that one only has to grind back far enough to ensure that the secondary bevel will be fully in new metal. In most cases that means that there is no need to grind all the way back to the primary bevel.


Grind the primary bevel until the secondary bevel is nearly gone, or gone entirely, then restablish the secondary bevel and keep it very slim.

[Derek Cohen]

Derek, thanks for the feedback...

The blade in the picture had a factory-ground 50 deg bevel. I ordered it long before I read your description of just honing a 50 degree bevel on a 25 deg blade... nowadays I would just order the 25. I may still grind it back to 25 degrees someday on my stationary sander. I've noticed that honing such a steep bevel freehand is difficult and prone to catches on the stones.

Hi Allen

I would seriously doubt that you are getting any camber on that blade. A few strokes at the sides of a 50+ degree bevel angle would do very little. The staight and even shaving you posted indicate this is so.

BU plane blades are one place where I recommend using a honing guide. I freehand all other blades, except BU plane blades. The honing guide offers reliability and repeatability of the bevel angle, and this is important on a BU plane. When you lift the edge, you really do not know what you are ending up with. A few extra degrees will reduce the "sharpness".

I most certainly would NOT follow Paul Sellers' advice on BU planes. I think PS is an excellent woodworker, and I have learned a lot from him, but he has incorrect ideas about BU planes. Most notably, his sharpening method is too imprecise for a BU plane on interlocked wood. He complains that BU planes tear out, but I see him sharpening at about 30 degrees, as he does for all his planes. That would end up with a cutting angle of about 42 degrees - far too low for most woods, let alone complex grain.

Try a blade with a 25 degree primary bevel, and a 50 degree secondary ... and use a honing guide.

Regards from Perth

Derek

[Mike Cherry]

The more experience I get under my belt, the less I like Powdered Metal blades. There is no free lunch, and in this case you are giving up sharpness for edge durability. Personally, I would prefer to sharpen more often to get a sharper edge, rather than have the same blade last longer. Especially when you become more comfortable with sharpening. That said, pmv steel does seem to last quite a while in my BU Jack when just flattening and edge jointing. But for chisels and final smoothing, I'll take O1 or Japanese steel any day of the week

[Allen Jordan]

Good point on the thickness of the blade reducing my cambering Derek. The shaving posted was full-width from the edge of a board, so there was no feathering happening. I haven't tried the newly-sharpened 50 deg blade on a wide surface yet to see if it leaves tracks, I'll give it a go later and see.

[Brian Holcombe]

Brian,

At the sake of sounding as though I'm disagreeing with you, I'll state that one only has to grind back far enough to ensure that the secondary bevel will be fully in new metal. In most cases that means that there is no need to grind all the way back to the primary bevel.

No worries Marty, and you are correct. However, talking about two different but similar goals. My reasoning for suggesting the small bevel is quite simple, it's easy to hone and being easier to hone it will be more accurate, especially when done by hand. It's difficult to repeat your microbevels free hand, so if you remove them or minimize to the point of near reduction then their replacement will be accurate.

So even when I do not remove the microbevel, I will grind on the primary until the microbevel is very small.

[Allen Jordan]

Occasionally I do grind a hollow to remove a large secondary/tertiary bevel using my 8" slow grinder, being careful not to overheat.

[Derek Cohen]

The more experience I get under my belt, the less I like Powdered Metal blades. There is no free lunch, and in this case you are giving up sharpness for edge durability. Personally, I would prefer to sharpen more often to get a sharper edge, rather than have the same blade last longer. Especially when you become more comfortable with sharpening. That said, pmv steel does seem to last quite a while in my BU Jack when just flattening and edge jointing. But for chisels and final smoothing, I'll take O1 or Japanese steel any day of the week

Mike, powdered metal blades theoretically should provide the finest edge. They do this in practice as long as you use the appropriate honing media. If you cannot do this, then stick to steels that suit your media. The durability of PM-V11 is especially apparent in chisels, where they are almost on par with Japanese white steel, and both are in another class to A2 and O1 in regards edge holding. But without the appropriate media (diamond, ceramic waterstones), they will not produce the edge they are capable of.

Regards from Perth

Derek

[Mike Cherry]

Thanks Derek, that's a great point. In my case, I do have diamond stones up to 1200 then I go shapton 2k and naniwa Snow White 8k. That is what you seem to suggest and I admittedly get a good edge, I just find I get a better edge with other metals(O1 in particular). For all I know, it's all in my head. I defer to the more experienced folk like yourself. As I mentioned, it definitely holds an edge for a good while. I sharpen often so I guess that is why the pmv seems wasted on me.

[Phil Stone]

Mike, powdered metal blades theoretically should provide the finest edge. They do this in practice as long as you use the appropriate honing media. If you cannot do this, then stick to steels that suit your media. The durability of PM-V11 is especially apparent in chisels, where they are almost on par with Japanese white steel, and both are in another class to A2 and O1 in regards edge holding. But without the appropriate media (diamond, ceramic waterstones), they will not produce the edge they are capable of.

Regards from Perth

Derek

Hi Derek,

Will regular waterstones not do an adequate job on PM-V11?

[Derek Cohen]

Hi Derek,

Will regular waterstones not do an adequate job on PM-V11?

PM-V11 will hone on most media from oil stones to ceramic waterstones, and between. It is just that some media will hone it more efficiently than others. With the less efficient media the danger is not doing a complete enough job, that is, stopping short of scratch removal or working to a wire edge. To increase the chances of a good sharpening one adds in method, and here the best recommendation is to reduce the blade area to a minimum. That is, work with a microbevel - either as a secondary bevel created on a honing guide or, as I prefer, a on a hollow grind, which allows one to freehand the bevel.

Regards from Perth

Derek

[Patrick Chase]

I realize this is a nearly-defunct thread, but...

The *entire* point of powdered metal steels is that they achieve finer grain structure (and in particular smaller carbide sizes) than would otherwise be possible for a conventionally processed steel of similar composition. Fineness of structure is the principle driver of "sharpness" as commonly defined by woodworkers, so Derek is spot-on in his reply: There should be no significant tradeoff in achievable sharpness from using a steel like PM-V11. In my experience it's comparable to low-alloy tool steels like O1, which achieves very fine structure even with conventional processing, and better than non-PM higher-alloy steels like A2 (though cryo treatment also refines grain structure and seems to close the gap in my experience). It may take different technique, sharpening media, and/or level of effort (as was the case here) to actually achieve that level of sharpness, though.

On a tangential note, it's interesting that Veritas came out with something called "PM-V11" not long after Crucible's patent on "CPM-11V" ran out. The material properties appear comparable, and Crucible's copyright/trademark remains enforceable (those run for a lot longer than patents) which would explain the different name.

[Allen Jordan]

Interesting to hear, Patrick. Thanks to everyone here for helping me find my sharpening problems with this steel. Amazing it takes 2-4x more work than A2 for sharpening on Shapton stones, but that kind of wear resistance makes for a good plane steel. I currently have PM-V11 blades in my Stanley No. 8C jointer, veritas edge-trimming planes, shooting plane, skew rabbet, and skew block planes (and my replacement LA jack blade mentioned in the first post). And now that my sharpening on them isn't quite so hit-or-miss, they should work even better.

[Mike Henderson]

On a tangential note, it's interesting that Veritas came out with something called "PM-V11" not long after Crucible's patent on "CPM-11V" ran out. The material properties appear comparable, and Crucible's copyright/trademark remains enforceable (those run for a lot longer than patents) which would explain the different name.
That's an interesting comment. I always assumed PM-V11 stood for "Powdered Metal, Version 11".

Mike

[Patrick Chase]

I've read enough old threads to know that this has been hashed over ad-nauseum and I'm not contributing anything new, but:

There is a fundamental tradeoff in stone design between hardness (and therefore dish resistance) and sharpening speed with difficult steels. Stones slow down when the abrasive particles are retained long enough to become dull. The "sweet spot" for any given metal (O1, A2, PM-V11, PM-HSS, etc) is therefore a stone that's just soft enough to release the abrasive right as it starts to dull. If the stone is harder than that then it will cut slowly. If the stone is softer then it will be uneconomical because it prematurely sheds perfectly good abrasive, and a pain to maintain because it goes out of flat quickly.

I'm an unreformed stone whore who owns a bunch of Shapton Pros and a sizable hoard of PM-V11 blades, and in my experience all but the 120 and 320 Shaptons are harder than ideal for PM-V11 and prone to slow cutting. In my opinion Stu's Sigma Powers are right about at the sweet spot for PM-V11, while Sigma Select IIs are too soft (though they're spectacular on PM-HSS...). For that matter I prefer Besters to Shapton Pros for PM-V11.

Technique also matters - A good technician can extend the "sweet spot" of any given stone in both directions by varying pressure, speed, honing pattern, and surface wetness, so I don't doubt that somebody will pop up and rightly claim they can cut PM-V11 at full speed on Shaptons. At some point you have to decide how much time and effort you're willing to spend optimizing your waterstones as opposed to just buying a softer set and spending those brain cells on actually working wood instead.

[Patrick Chase]

In the case of CPM-11V it stands for "11% Vanadium".

Note that a conventionally processed (non-PM) steel with that much Vanadium would likely end up a grainy mess of carbides.

The original patent covering CPM-11V is http://www.google.com/patents/US4249945 and ran out long ago, but there are subsequent patents up to ~1991 that might be necessary to actually manufacture high-quality parts (I have some academic training in metallurgy, but it's been an awfully long time and this is relatively advanced stuff). Those ran out shortly before PM-V11 hit the market.

Does anybody out there have a mass-spec machine and a PM-V11 blade they'd like to sacrifice? :)

[Jim Koepke]

Patrick, Welcome to the Creek.

I am always curious as to the area of the world one calls home.

Thanks for sharing your information on steel and stone. Good explanations in compact form.

jtk

[Patrick Chase]

Location fixed :)

[Jim Koepke]

Location fixed :)

Interesting, I retired from BART. Would occasionally get out to Dublin. Used to visit a Woodcraft store there at times.

jtk

[Kees Heiden]

It is probably not the same as CPM-V11. It doesn't have that much vanadium. I don't think it has much vanadium at all. Vanadium carbide is very hard and difficult to sharpen, even grinding takes ages. PMV-11 isn't like that at all. It is about twice as much work as O1. It is definitely a stainless steel though. So, more a steel like 440C or D2. But it is tempered to a higher HRc value then these usually are.

When you search around for powder metal steels you will find that most contain a significant amount of vanadium, because vanadium steel is very wear resistant and in the industry they use it for pressing dies, for example in the automobile industry. The difficulty of sharpening isn't that important for them.

So when you sum up the properties of PMV-11, it isn't too difficult to find good candidates.
- Stainless steel, so it contains a lot of chrome
- Relatively easy to sharpen, so not a huge amount of vanadium (rules out a lot of readilly available steels)
- Powder metal
- Can be hardened to high HRc values, 61 to 63 according to LV. That's more then standard 440C or D2.
- A guess from me: it is most probably a standard knife steel, made in America, because they are so secretive about it. Not something special from Japan, more difficult to get.

A good candidate that ticks all the above boxes is Carpenter CTS-XHP. Essentially an improved, PM version of 440C. http://cartech.ides.com/datasheet.aspx?I=101&E=343

BTW, the powder metalurgy steels have a fine grain compared to similar high aloy steels made in the traditional manner. But high carbon steel still trumps them all in this respect.

[Patrick Chase]

That Woodcraft went belly-up just before I moved here (which is probably a good thing for me - less temptation to binge-purchase so-so tools). The only one in the BA is in San Rafael now.

[Patrick Chase]

Yes, now that I think about it you're almost certainly right. While I don't have direct experience with high-Vanadium PM steels, I know that Derek was unable to put a fine edge on CPM-V10 using Shapton Pros for one of his metal comparisons, and that puts it in a completely different league than PM-V11. Thanks for the correction!

On a related note, IMO the fact that Veritas/LV haven't patented or done a defensive publication for PM-V11 is a dead giveaway that it's either somebody else's steel or in the public domain.

The notion that they have IP around the composition (as opposed to the process) and are holding it as a trade secret is patently absurd (pun intended). I used to sit on IP review committees for a former employer, tasked with deciding whether to patent, publish, or trade-secret-ize invention disclosures. The cardinal rule of trade secrets is that you must be confident that you can actually keep them a secret. There are a few reasons why this is so:

1. Trade secrets are only protected from theft, not from independent analysis. If a competitor bribes my employee to steal my secret then I can pursue legal remedies against both. If my competitor or some other party legally acquires my product and reverse-engineers my "trade secret" then I have no protection or recourse (unless the analytic approach they used is specifically prohibited, for example by the infamous DRM provision in the DMCA). The proverbial cat is out of the bag at that point.

2. If I keep something a secret and somebody else subsequently invents the same thing independently (not via reverse-engineering), then they can usually patent it and prevent me from using it even though I developed it first. Prior art must be public to forestall subsequent patents, and that's precisely why it's very common to defensively publish inventions that you choose not to patent but that you don't think can be kept secret. There are entire journals dedicated to such publications (which exist for additional reasons that I won't go into here, except to note that sometimes you want a publication that you can subsequently point to when advantageous but that nobody is likely to find on their own. My current employer made that a whole lot harder to achieve, though, and IMO that's a good thing).

3. If I keep something secret and somebody else reverse-engineers it and publishes their analysis, then that publication is *their* intellectual property (via copyright) and I have no control over it whatsoever. Again this is a reason to preemptively publish.

Steel composition can be trivially determined via common analytic methods, so I think it's safe to conclude from the lack of publication/patent that Veritas/LV either hold no IP around the composition, or are the victims of extremely poor legal advice.

Disclosures: I'm an engineer, not a lawyer, though as noted above I have experience in this area. Also, I've simplified in a couple respects to keep things readable.


It is probably not the same as CPM-V11. It doesn't have that much vanadium. I don't think it has much vanadium at all. Vanadium carbide is very hard and difficult to sharpen, even grinding takes ages. PMV-11 isn't like that at all. It is about twice as much work as O1. It is definitely a stainless steel though. So, more a steel like 440C or D2. But it is tempered to a higher HRc value then these usually are.

[Kees Heiden]

Completely agree. It is like making the weight of your new doodad a trade secret. Everybody with access to a scale can break your secret, after which it stops to be a secret. Really, this situation isn't any different.

[Mike Henderson]

Good discussion - thanks. I'm pretty sure that LV sources that metal (the PM-V11) from a North American source. I had a conversation with Rob Lee where he commented that he wanted his tools to be made in NA with material from NA. I think they specifically indicate if a tool came from other than NA.

I really doubt if they have any IP in that metal.

Mike

[Kees Heiden]

Last spring, over on woodcentral a guy named Bill Tindal posted that he put one of his PMV chisels in such a mass spectro machine. There was quite an uproar if he should publish the result or not.

[bill tindall]

It is not CPM 11V

[bill tindall]

Not mass spec. Analysis is done by nondestructive X-ray fluorescence. Can be done in 30 seconds on any flat surface.

[Andrew Pitonyak]

I've read enough old threads to know that this has been hashed over ad-nauseum and I'm not contributing anything new, but:

Yeah, I can finish that with.... "but... then Andy learned something because Patrick posted".

There is a reason that you see article types repeated in magazines over the years. Even if some of the old-timers know the stuff, new people do not know it and some of us forget some of it. For example, I had no idea which of Stu's stones was best for PM-V11. I keep thinking that I should add to my water stone collection and try them, but what I have works and buying more is just so addicting!

Keep posting Patrick!

[Patrick Chase]

Not mass spec. Analysis is done by nondestructive X-ray fluorescence. Can be done in 30 seconds on any flat surface.

Depends what you want to know, right? IIRC XRF can't do Carbon.

[bill tindall]

The question was how to identify what alloy it was and that quest did not involve mass spectrometry, nor is it likely any chemist would pursue that route. I didn't need carbon to identify the material (in this case), nor did I need to sacrifice any tool.

[Pat Barry]

The question was how to identify what alloy it was and that quest did not involve mass spectrometry, nor is it likely any chemist would pursue that route. I didn't need carbon to identify the material (in this case), nor did I need to sacrifice any tool.
Well, what did you learn? Even if it is a trade secret, the fact that virtually anyone who needs the information can easily get the answer through simple techniques such as XRF means that it really isn't secret at all.

[Patrick Chase]

Well, what did you learn? Even if it is a trade secret, the fact that virtually anyone who needs the information can easily get the answer through simple techniques such as XRF means that it really isn't secret at all.

Having looked through the thread on the other forum, I have a few thoughts:

1. There are some people in our community who appear to have no idea why intellectual property works the way it does. The system is intentionally biased to promote disclosure, whether by patent or publication, because we don't want to return to the old progress-inhibiting system of medieval guilds. One dark age was enough, thanks. I'm not arguing that our current system is remotely ideal (IMO SW patents are a disaster), just that there's a sound reason for biasing toward disclosure in any such system.

2. As noted above the analysis is Bill's IP (via copyright) to do with as he chooses.

3. Given the amount of (IMO unwarranted) anti-disclosure vitriol in that thread I'd probably keep my head down, too.

If you want to know then take your blade to any of the very large number of services that provide XRF.

[Pat Barry]

Having looked through the thread on the other forum, I have a few thoughts:

1. There are some people in our community who appear to have no idea why intellectual property works the way it does. The system is intentionally biased to promote disclosure, whether by patent or publication, because we don't want to return to the old progress-inhibiting system of medieval guilds. One dark age was enough, thanks. I'm not arguing that our current system is remotely ideal (IMO SW patents are a disaster), just that there's a sound reason for biasing toward disclosure in any such system.

2. As noted above the analysis is Bill's IP (via copyright) to do with as he chooses.

3. Given the amount of (IMO unwarranted) anti-disclosure vitriol in that thread I'd probably keep my head down, too.

If you want to know then take your blade to any of the very large number of services that provide XRF.
Harrumph!!

[Steve Voigt]

I'm a little late here but I wanted to add a couple thoughts.


Mike, powdered metal blades theoretically should provide the finest edge.

Derek, what evidence is there that PM V11 provides the finest edge? I'm not agreeing or disagreeing; I'd just like to know if there is data, even if it's subjective observation. Veritas seems to have done excellent and thorough testing, but it was limited to ease of sharpening, impact resistance, and wear resistance. I have to say, if it does provide the finest edge, I'm pretty sure folks would be announcing that from the hilltops…


I realize this is a nearly-defunct thread, but...

The *entire* point of powdered metal steels is that they achieve finer grain structure (and in particular smaller carbide sizes) than would otherwise be possible for a conventionally processed steel of similar composition. Fineness of structure is the principle driver of "sharpness" as commonly defined by woodworkers, so Derek is spot-on in his reply: There should be no significant tradeoff in achievable sharpness from using a steel like PM-V11. In my experience it's comparable to low-alloy tool steels like O1, which achieves very fine structure even with conventional processing, and better than non-PM higher-alloy steels like A2 (though cryo treatment also refines grain structure and seems to close the gap in my experience). It may take different technique, sharpening media, and/or level of effort (as was the case here) to actually achieve that level of sharpness, though.

Patrick, I'm not sure what to make of the above quote. By "steel of similar composition," you presumably mean something like A2 or HSS, although it's hard to know, since I (we?) don't actually know the composition. Or do you mean O1 or 1095? Similarly, when you say "it's comparable [in achievable sharpness] to low-alloy steels like O1," do you mean it gets as sharp, or a little sharper, or not quite as sharp?

It might seem like I'm nitpicking, but I don't think so. To me, the most important question is what steel(s) get sharpest? Ease of sharpening is second, and edge retention is third. In the past, all the research into "wonder steels" was focused on the third category, I suppose in the rather futile hope that beginners could avoid sharpening forever. With PM V11, Veritas at least seems to be acknowledging the problem with these steels (like A2 or CPM whatever), that they fall short in the first two categories; from all accounts PM V11 gets sharper, and is easier to sharpen, than something like A2. But I don't really care. I want to know if something gets sharper than O1, 1095, or Japanese blue or white paper steels. If someone can show me that Pm V11, or anything else, actually takes the finest edge, I will run out and buy it tomorrow. But until then, I'll stick to the steels that are simplest and purest. My personal feeling, as Mike Cherry said above, is that there's no free lunch.

[Kees Heiden]

I am pretty sure that PMV-11 is a stainless steel. I actually tested that, trying to get the steel to rust. While O1 readilly turned brownish/blackish and A2 got some tarnishing too, PMV was unaffected. To make a steel stainless it needs a bunch of chrome, or a bunch of nickel, or both. At least 14% if I remember correctly. The chrome that isn't occupied with the chromium oxide layer on the outer skin of the steel will form chromium carbides. That stuff is hard, not as hard as vanadium carbides, but still harder then ferrum carbides (cementite if I remember correctly) and certainly harder then the tempered martensite structure that makes up most of the body of a well hardened steel.

Now I am going out on a limb. I suspect that the chromium carbides don't like to be abraded by our sharpening media, except diamonds. I think they prefer to be ripped out of the steel structure, leaving behind craters. I have seen a picture of a powdered metal on a knife forum (not PMV-11, another one) where the chromium carbides were still several micrometers large. A lot better then in good old fashioned D2, but still not quite as small as a good sharp edge is supposed to be.

All this probably doesn't make a difference when you stop sharpening on a 1000 grit waterstone...

[Patrick Chase]

All this probably doesn't make a difference when you stop sharpening on a 1000 grit waterstone...

I sharpen to a level that optimizes woodworking performance, and my comments were made in the context. Sorry I wasn't more clear.

In particular, I hone to <=1 micron abrasive size on both waterstones (Sigma 13K or Shapton Pro 15K) and diamond (0.5 micron paste or 0.5 micron 3M 661X/668X film). I don't notice a difference in keenness between my PM-V11 and O1 blades in practice, though I do notice some (negative) difference between those and non-cryo A2 blades (the A2 blade from my L-N #8 on the other hand takes a very nice edge indeed). I've also examined blades under 'scopes and didn't see multi-micron craters in the PM-V11. Note that the specifics of the sintering process come into play as well, so even if you looked at another "PM" steel with the same composition your observations wouldn't necessarily carry over to PM-V11.

I'm sure that a straight-razor fanatic would hone to a different level and draw different conclusions.

[Mike Henderson]

I finish on a Shapton 8000 stone and that's sharp enough for me. I mostly use my chisels for chopping so after a couple of hits, some finely prepared edge is gone.

If I can shave hair with my chisel, I figure it's sharp enough.

If I have to pare, I go back to my 8000 stone and make sure the chisel is in just-sharpened condition.

Mike

[Patrick Chase]

Harrumph!!

I would note that sometimes what is not said is far more significant than what is.

[Derek Cohen]

Derek, what evidence is there that PM V11 provides the finest edge? I'm not agreeing or disagreeing; I'd just like to know if there is data, even if it's subjective observation. Veritas seems to have done excellent and thorough testing, but it was limited to ease of sharpening, impact resistance, and wear resistance. I have to say, if it does provide the finest edge, I'm pretty sure folks would be announcing that from the hilltops…

It might seem like I'm nitpicking, but I don't think so. To me, the most important question is what steel(s) get sharpest? Ease of sharpening is second, and edge retention is third. In the past, all the research into "wonder steels" was focused on the third category, I suppose in the rather futile hope that beginners could avoid sharpening forever.

Hi Steve

The short answer is that, in my understanding - hence the "theoretical" addition to my comment - PM steel is capable, depending on the recipe, of having a finer grain structure than steels prepared in a less precise way. Added to this, I was informed that PM-V11 is one of those recipes that is aimed at a fine grain structure. I have no reason to not believe my source.

What I can state, which is factual and not theoretical, is that I have compared a number of steels in a real world manner, and the results backed up the claims for PM-V11. It is a steel that both gets very sharp, and also holds that edge extremely well. It far, far outclasses O1 and A2 in the latter area when it comes to chopping through end grain with a chisel (as expected in dovetailing), only just pipped by the Koyamaichi white steel chisel I used in a comparison.

I do not have any trouble getting steels - any type – sharp. Getting sharp just requires the appropriate honing medium for each particular steel you use (some media will obviously work a wider range than others; some a very narrow range). Not all media suit all steels. Getting sharp is important, but equally so is maintaining that edge. The woods I work are hard and abrasive (high silica content). As soon as the edge dulls, the tool’s performance drops off. For illustration, comparing the LN #51 shooting plane and the LV shooting plane, it was easily demonstrated that O1 steel dulled very rapidly. It matters far less whether it was capable of equaling or bettering PM-V11 in sharpness since it dulled so rapidly that it was essentially an obstacle to good work.

The “wonder steels” have an important and relevant role to play. Just perhaps not for everyone. And they are certainly not a “beginners” steel. For myself, this is serious steel, which hopefully helps me do serious work.

Regards from Perth

Derek

Links: http://www.inthewoodshop.com/ToolReviews/LVShootingPlane.html

http://www.inthewoodshop.com/ToolReviews/FourChiselSteelsCompared.html

[Patrick Chase]

Hi Steve

The short answer is that, in my understanding - hence the "theoretical" addition to my comment - PM steel is capable, depending on the recipe, of having a finer grain structure than steels prepared in a less precise way. Added to this, I was informed that PM-V11 is one of those recipes that is aimed at a fine grain structure. I have no reason to not believe my source.

A more accurate way of stating that would be: "PM steel is capable, depending on the recipe, of having a finer grain structure than steels of similar composition prepared using conventional processing". Steels that are high in certain alloyants tend to form coarse grain structures and large carbides with conventional processing, and PM prevents that from happening. Also, it isn't a question of more or less precise.

That is not however to say that such a high-alloy PM steel would be expected to have a finer grain structure than a conventionally processed low-alloy steel like O1, which has inherently fine structure without resorting to PM. PM expands the range of compositions that you can use while still achieving a given level of "sharpness", but it isn't a silver bullet. In my experience PM-V11 is more than good enough for woodworking, though.

[Kees Heiden]

Funny thing about your chisel test Derek, is that the Japanese white steel and the PMV-11 scored almost the same. And they couldn't be more different. The White steel has almost no alloying elements, a little bit of silicone that's all. While PMV-11 contains almost 20% of stuff that isn't iron or carbon.

I suspect that in a chisel high hardness (resists deformation and increases wear resistance) and fine grain (increases toughness) are important aspects.

[Derek Cohen]

I suspect that in a chisel high hardness (resists deformation and increases wear resistance) and fine grain (increases toughness) are important aspects.

Hi Kees

What I found interesting in the tests I conducted on chopping vs paring with chisels was that they produced such different results. Where White Steel (Koyamaichi) left all for dust in the chopping, it did not perform this well in the paring test ...

"The A2 and O1 blades were almost as good as the WS, really only a little behind. I’d place the O1 fractionally ahead of the A2 in the first 25 strokes and at the end of the experiment. The extra durability of the A2 was not evident in this assessment.

Impact vs abrasion resistance differences?

This was done prior to the advent of PM-V11, and so this was not compared.

Regards from Perth

Derek

Links: http://www.inthewoodshop.com/ToolReviews/ChiselBladeTesting-5Steels.html

http://www.inthewoodshop.com/ToolReviews/ChiselParing.html

[Kees Heiden]

Yes, I think in a plane an iron dulls in a different way then in a chisel. And pairing with a chisel has more in common with a plane. The dulling effect during chopping is harder to grasp in a theoretical model.

White steel hasn't anything specific to reduce the abrassion. Apart from the high hardness like in many of those nice Japanese chisels. As far as I know the major abrassion resistance factors are hardness and chemical composition.

Toughness can be advanced with some alloys, with lower hardness, but also with a very fine grain of the steel.

[Pat Barry]

The grade stamp on the steel isn't always going to be a true indicator of how it will perform as there can be a significant difference in material composition, manufacturing process and treatment process variability and perceptible things such as finished hardness within any of the steel categories. In other words, one mans O1 isn't necessarily the same as another's because they didn't come from the same steel supplier / factory. I speculate that this is less the case with the PMV11 as it is most likely a single source supplier and because of that, many of the variables noted above are reduced or eliminated.

[Brian Holcombe]

I don't have the need for it, but I wonder how something like blue 2, worked by Konobu or Kikuhiromaru would perform in the paring test.

Derek, in practical use, how do you feel your Kiyohisa's perform in paring against these other steels.

[Derek Cohen]

Hi Brian

The Kiyohisas are in a class of their own. They are very easy to hone, and yet hold an edge for such a long time. Keep in mind, however, they are slicks and do not get used in a rough manner - fine paring only.

Regards from Perth

Derek

[george wilson]

Derek,Wonderfully complete and logical test you did on the LV and LN shooting planes referred to in your link listed above.

[Derek Cohen]

Thanks George

Derek

[Brian Holcombe]

Hi Brian

The Kiyohisas are in a class of their own. They are very easy to hone, and yet hold an edge for such a long time. Keep in mind, however, they are slicks and do not get used in a rough manner - fine paring only.

Regards from Perth

Derek

I have similar experience at this point with the Konobu's and similarly happy with how they sharpen and how they wear. I'm not sure exactly how my Kikuhiromaru stack up against Kiyohisa (or Kiyohisa Kamon) but they're held in high regard by So and I've used them quite extensively at this point and very happy with how they wear. Which is driving my question, to some degree, I do wonder how Blue 2 would hold up against the woods you commonly use.

If I used exotics to a higher degree I would venture down that path, but HC steel does everything I need and does it very well, so I have not really ventured into blue 2 by the 3 K's.

If nothing else I'm curious as to your decision making with regard to use of blue 2 in conjunction with your use of jarrah.

[Derek Cohen]

If nothing else I'm curious as to your decision making with regard to use of blue 2 in conjunction with your use of jarrah.

Hi Brian

It's not complicated. I was looking for good slicks, and So recommended Kiyohisa. Keep in mind that this was about 8 or more years ago now, perhaps 10 years, and Kiyohisa were little known in the West. There was a waiting list - I ended up being on it for 3 years (and it could have been longer), but at the time I expected about 12 months. So said that Kiyohisa was excellent, among the best, but a rising maker. I looked at his work and liked the simple aesthetic, and put in my order. Then I checked in every year or so ... :)

I did not think about white vs blue steel. It did not matter. It still does not matter. Some steel is just a beginning, and it is the maker of the tool that matters - how they work the steel, and create the blade.

What does matter is that these are all I hoped for in a slick. They are simple looking, but wonderfully balanced and a real joy to use. I never consider changing them for something else.

http://i13.photobucket.com/albums/a262/Derek50/Chisels/Kiyohisa/8.jpg

Regards from Perth

Derek

[Brian Holcombe]

I feel similarly, the quality of maker is of top importance, and I tend to lean on makers who use white 1 and HC steel primarily because those are best for me. They sharpen easily using natural stones. So has mentioned it to me occasionally that Konobu and Kikuhiromaru both also make using blue 2 and that the steel is a good choice for exotic woods, exotics being a bit of a rare bird for me so I stick with white 1.

I'm very happy with my choices and they play well with how I use and sharpen my tools, but playing devil's advocate a bit because I see these steels like PM-V11 compared to A2, o1 and white 2.....I dont really see them compared to white 1 or blue 2....or if they have been compared I've managed to miss it. It would make sense to me to compare the PM-V11 to Blue 2.

The maker should be focused on much more in these discussions. I've used my kikuhiromaru white 1 in renovation work in addition to cabinet making and they have not even winced at being knocked through knots and such. Not abusing them by any stretch, but for all this mention of a few chops being the end of a fine edge, it has not been my experience.