Sharpening D2 on Arkansas Stone

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sjahn

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Hello, I have a question regarding sharpening D2 blade.

I have BM211 model with D2 steel. It's my first D2 knife, and I got to love D2 steel.
I sharpen my knives with medium grit arkansas benchstone. (I tried a couble of sharpening systems, and different bench stones like ceramic, aluminium oxide, then I found I'm most comfortable with arkansas stones.)
After some trials, finally I got some sharp edge on the blade. The problem is, it forms fine burr readily and it's a bitch to remove. They say D2's tough steel, yeah, even burr is tough! It just doesn't go away.
I searched forum, but cannot find any direct quote regarding burr formation on D2. I know any steel can form burr, but this one blade forms burr readily and quite difficult to remove.
I haven't had this problem with 154cm and 440. I've seldom seen burr formation on my 154cm blades, those burr on 440 goes away quick.
Burr on D2.. They're very fine, and they don't go away.
I was able to remove most burr by sharpening on fine benchstone about half an hour, but even then, small patches of burr still remain on the blade.
I've tried several methods suggested for removing burr with mixed results.

The question is,
Is D2 forming fine burr readily normal?
And what'd be good way to remove those fine burr?

So far, I find that carefully sharpening on fine stone for more than half an hour works best for me. (I tried other methods, but I found this one works for me.) While it works, it seems that it's too much effort. For a blade less than 2" long, it needs quite some attention maintaining.

Thank you in advance for any suggestions or direction to any missed thread, articles.
 
:)
Yup. I've already read it and did everything suggested. (I scrapped it and other articles regarding burr removal, actually.)
The problem is, after removing burr following the direction Jeff Clark suggested, when I retouch the blade to restore the edge, a new burr formed! Also, it took quite many light stokes on my fine stone removing burr on this blade. Not just a few alternate sweeps...
Raising the angle helps, but as I said, when I tried to restore the edge after removing burr, new burr formed more often than not. Maybe it's my incompetence...
I followed what yuzuha suggested, it worked, but not as good as I'd like. (more likely because I'm not familiar with the method) Also, when I tried to reshape edge after deburring, new burr formed. :(
I've found other articles/threads and followed their suggestions. So far, spending long time with gentle stroke on fine stone worked best.

I have to spend more time, then. There's no magic, I guess.

Just this one question, then.

Is it normal for D2 to form very fine burr?

The burr is so fine I can hardly feel it with my finger nails, but I can see it glints off light. One day, I was fed up with spending half an hour removing burr, so I just skipped it. I sharpened the knife, and seeing fine burr formed on it, but nothing prominent, I just ignored it. The knife dulls quickly. :(

Gotta remove those burrs...

Thanks anyway. Good to recheck if I was missing anything.
 
I have had problems exactly like you describe with D2 in the past, it was solved readily using diamonds which produced a clean edge with no burr. What I think it happening is that since the diamond stones can cut with less force there is less tendancy for the burr to be deformed and flop to the other side and more of an ability for it to cut off. However since then by refining technique I have sharpened it successfully on other stones, it just takes more care when you have less aggressive hones because there is less tendancy for abrasion vs other material effects.

At a basic level it is as simple as this - when you hit the edge with the stone it will either crack off, bend over, get directly impacted, or be abraded. Only if it is abraded will it get sharpened, the other effects will reduce the sharpness. It is rare that the edge gets impacted, this only happens if the stone is really uneven. Cracking off is also rare, it is usually caused by improper hardening though can be an issue on japanese knives. If you are getting fracture then the edge simply won't form.

To prevent the edge deformation burr from forming all you have to do is raise the ability of the stone to cut into the steel and minimize the ability to smash it to the side. This is why raising the angle helps because it reduces the force sideways on the edge. What I would suggest is to cut off the weakened metal on the edge directly, lapp the stone flat and then regrind the edge to a full burr. Now clean the surface of the stone, elevate the angle and just use a few passes to deburr the edge.

If the edge doesn't have the burr removed very quickly, as in 1-2 passes generally it isn't going to be removed, however at times I have seen benefits from going as much as 10 passes per side, but if you go beyond that then you are not really doing burr removal any more as much as just creating an additional edge at a higher angle.

If this still doesn't work then you can try a more aggressive stone or some stropping on a very aggressive compound like boron carbide or diamond. You might also want to try sharpening the edge as best you can and then a very light pass directly into the stone to cut off the burr (and some of the edge) and then see if stropping on 0.5 micron chromium/aluminum oxide (or a more aggressive compound ideally) will restore the edge without forming a burr.

The blade by the way could also be damaged in the heat treating. If it was oversoaked, or not tempered quickly after hardening, it would lead to problems just like you describe and be pretty much impossible to sharpen. So you also might want to see if you can handle another D2 blade. Ideally you could also have someone very familiar with D2 have a look at it and thus eliminate or confirm that it is a steel problem.

-Cliff
 
I think you may be getting more burr because, while you like the feel of Ark. stones, they are basically just silica with a moh's hardness of 5.5 or so. That is plenty hard enough to grind plain iron and steel but is softer than the carbides in D2. D2 has big carbides and instead of actually sharpening them, you are just wiggling them out of the steel matrix leaving a softer spongy strip along the edge that gloms together and forms your burr (pretend you are a germ and your knife blade would seem like it is made of little carbide marbles in softer modelling clay-like iron... your Ark. stone can abrade the iron off but can't cut the marbles, just scrape them loose). Since you like your stones, I'd suggest using them to the point you are doing, then take the burr off and gently finish on something a bit harder, like an xtra fine diamond plate (will give you a finish close to a 1000 grit waterstone), or wet-or-dry silicon carbide paper (silicon carbide is moh's 9.5), ceramic waterstone or something that can actually cut the carbides. If you take the marbles in clay analogy further, you'll see that once you have a sharp edge, it will need to be thick enough to have enough iron surrounding the carbides to hold them firmly, so D2 works better with less acute edge angles (30-40 degrees total edge angle should give you a meaty enough edge to hang onto them in normal use).
 
Oh, another thought.... if you want to finish on a hard Ark. stone, you could just add a pea of 1 to 3 micron oil based diamond paste to the stone to make it more agressive.
 
I know for one thing, if you buy a Ka-bar, the instruction manual says to use arkansas stones on their 1095 cro-van, but if you buy the d2 the manual says to use a diamond whetstone.
That should be a good indication right there that arkansas stones, though really cool, will not do a good job on d2!
 
haha yeah. Whats wrong with talking on an old topic? I guess its just a thing to be the first person to say "this topic is old" "your a necromancer"
Sorry dude jeeze, i'm sort of a geek with some knife stuff and none of my real life friends are into it! Got no one to nerd out with on the topics...
 
Make your own thread if you want to talk knives, talking to the "dead" is just weird.

The OP of this thread has not even logged-in for the past 6 years
 
no one is "dead" man, and I had typed something related into google about this, and this thread came up. I happened to be a member so I commented.
When I start new threads someone just hops on and links me to an old thread, if I post on an old thread someone tells me i'm talking to the dead. COME ON!
 
I don't mind resurrecting this thread. It is short, it is focused on a specific topic, it is a common topic, still appropriate.

This squabbling over resurrection itself is a waste of time and may deter others from adding to the legitimate discussion.

We don't need it. Closed.
 
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