Sharpening Japanese Knives

Recently I got myself a set of Eden Kanso Aogami steel knives.



On the 2nd day, lucky me, the Gyuto chipped at the tip as it dug into a cutting board as I was cutting and twisted it as it entered.
I sort of took the chip out, by rounding the minimal amount of edge as possible on a 1000 grit stone. That very tip isn't sharpened and still not 100% correctly shaped, but I can live with it.

I read some knives come with a very steep angle from factory and tend to chip quite a bit, so I figured this is normal, but, I'll have to get good at sharpening. I plan to buy a King Combo 1000/6000 waterstone by the end of the month, but as of now I have a cheap 1000 grit stone, I got it for 2.00$ at a local asian market. The packaging said Naniwa but I doubt it's legit. It fizzes when it goes into water, but dries out quite fast when sharpening, have to keep constantly re-moistening the surface.

Anyway, these knives came with a weird problem for me. On most knives I have at home, cheap, but fairly sharp (as much as I can get them), I can see a small bevel, on both sides, leading up to the very edge. I'm not 100% sure what angle I'm sharpening at but I would say 18-20. On the Eden knives, I only see a microscopic bevel reflecting light on both sides, but it is SUPER tiny and would have to be made at a really high angle. I believe they call this a microbevel?

This brought the question: when I do sharpen these knives, what angle should I go for? Should I go from the shinogi line down to the edge, thinning and sharpening at the same time? Should I do that, and then add a microbevel? Or should I just put a 15 degree angle on it?

Apologies from a confused sharpener :rofl2:

P.S.: They have started developing a beautiful purple/blue patina after just a few days, food reactivity is non-existent after the first onion and rust is still at bay and they came quite sharp, so all in all I'm quite happy with them!

Your technique and knife skills will determine what angle you should sharpen at. If you are experiencing chipping, either sharpen at a more obtuse angle or add a microbevel. I find 15 or a little less is adequate to keep up with my technique without chipping on aogami super. You need to find what is right for you and adapt as your skills improve. There is no "correct" angle for a particular steel, there is, however, a "correct" angle for a particular steel for the way you cut.

Welcome to the forums.

DWalker gives some sound advice.

Note that the factory edge in some knives is quite weak.

From your desription, I'm not 100% sure how you did the tip repair. The two that I have done (none more than 2mm) I have ground the spine until it meets the intact edge. Avoids having a blunt tip.

You can check the given angle by moving the blade edge leading on a cutting board. Lift the spine until the edge catches the board.

dwalker said:

Your technique and knife skills will determine what angle you should sharpen at. If you are experiencing chipping, either sharpen at a more obtuse angle or add a microbevel. I find 15 or a little less is adequate to keep up with my technique without chipping on aogami super. You need to find what is right for you and adapt as your skills improve. There is no "correct" angle for a particular steel, there is, however, a "correct" angle for a particular steel for the way you cut.

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Okay sounds good. I tend to over worry about stuff like this. I wanna keep them to their best performance and looks. So I'll eventually put a 12-15 degree angle on it with a microbevel for resistance if I need it by then. At would degree would the microbevel be at? I'll rely on the sharpie trick for the angle + eletrical tape to prevent scratching up the blade.

Nemo said:

Welcome to the forums.

DWalker gives some sound advice.

Note that the factory edge in some knives is quite weak.

From your desription, I'm not 100% sure how you did the tip repair. The two that I have done (none more than 2mm) I have ground the spine until it meets the intact edge. Avoids having a blunt tip.

Click to expand...

Thanks! Yea, I'm an absolute noob on grinds/bevels, but this confused the heck outta me. By looking at the blade I can't tell for sure where the sharpening took place and it's a high-flat grind with a microbevel on the edge. I'll post pictures later to see if you can help me decipher.

Yea, I heard people do that, but didn't want to scrub out the kurouichi finish on the spine. Minor detail, but yea, you can always resharpen the blade, but when that kurouichi is gone, it's gone.. It's just the very very tip, not performance issues even tho it's blunt, i'll fix it up when I have to sharpen them.

natto said:

You can check the given angle by moving the blade edge leading on a cutting board. Lift the spine until the edge catches the board.

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So that gives me the microbevel angle right? Because that is the very cutting edge? Also, not sure I would do it on a cutting board, that's how I broke the tip last time.


On addition to the King Combi, I'm thinking of getting a pack of 3M microfilm of a few grits. One equivalent to over 8k grit and one over 10k maybe. Is leather a finer grit than these, or can you get a stropping compound that fine? Cheers

[video=youtube;xwnFrjiAA_8]https://www.youtube.com/watch?v=xwnFrjiAA_8[/video]

miggus said:

[video=youtube;xwnFrjiAA_8]https://www.youtube.com/watch?v=xwnFrjiAA_8[/video]

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Interesting. But when the knife gets dull, or isn't as sharp, can I just add/maintain the microbevel instead of doing the regular sharpening? I'm super afraid of scratching up the sides of the knife, even with eletrical tape covering it up. Taking a steeper angle and adding a microbevel reduces this risk as less of the knife makes contact with the stone..

Aogami said:

So that gives me the microbevel angle right? Because that is the very cutting edge? Also, not sure I would do it on a cutting board, that's how I broke the tip last time.

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Yes and no. You still want to back off a little bit when you find where the knife bites into the board in this case but I would just do this on the stone so you are already where you need to be to sharpen. You should not break the tip because you should not be leaning into the knife when you do this and you can find the angle at the belly too and then just adjust for the tip by raising your elbow and rocking the knife.

If you were to start right where the edge bites into the stone you are going to end up with a more obtuse angle every time you sharpen. So, back off that angle a bit as I said. Also, back off a little further to thin behind the edge.

Aogami said:

Interesting. But when the knife gets dull, or isn't as sharp, can I just add/maintain the microbevel instead of doing the regular sharpening? I'm super afraid of scratching up the sides of the knife, even with eletrical tape covering it up. Taking a steeper angle and adding a microbevel reduces this risk as less of the knife makes contact with the stone..

Click to expand...

You can maintain a microbevel for some time be after awhile it is going to need to be reset and after even more time your bevel is going to become obtuse as well. With Japanese knives thinning on the blade road just comes with the territory. Take a look at the uchigumori thread and some others, you can put that nice finish back on your knife! It takes the right tools and some learning, though.

Okay, thanks for clarifying a bunch of stuff.

I'll sharpen with the sharpie and tape aids at 15-ish degrees when I need to, form a new secondary bevel to my liking and gather some courage to thin the blade road when I need to.

By putting that nice finish back on my knife, you mean by thinning the blade road will "scratch" and remove it's finish, but I can re-polish it back to shape, right?
I got some sanding paper and abrasive sponges to start polishing a few dollar store knives I have laying around, I believe the process would be similar and sandpaper of a high grit would suffice to give a nice finish?

No wide bevels here. So you start sharpening on one side, at a low angle, and raise the spine little by little, until you raise a burr on the opposite side. Do the same at the other side, starting far behind the edge. Yes, you may scratch the blade. It's a tool, and deserves a better edge than the factory one.