Can't get my Kohetsu AS knife as sharp as others

[raleighcook15]

Curious why I can't get the same hair splitting edge on my Kohetsu AS 240 that I can on my yuki. I understand they're different steels (white 2 vs as) but I didn't think that would make as large of a difference. I use an edge pro with the standard stones and then strop on a leather paddle.

[Kit Craft]

I have not used that knife but not all knives are created equal. My Yuki, while not one of my favorite knives, I feel has a better heat treat than most any knife I own. It takes a very, very fine edge and holds it a lot longer than any other white number two steel that I own. I guess it could be any number of things though.

[HectorFuego]

My experience with a Kohetsu AS 240 has been that it performs better with more bite. Last time I sharpened it I stopped at 1000 grit and gave it a few strokes on a leather strop. It may not look as shiny/pretty as a 6000 grit polish but, lordy, does it blaze through produce.

Just a thought.

Howard

[Jason H]

Curious why I can't get the same hair splitting edge on my Kohetsu AS 240 that I can on my yuki. I understand they're different steels (white 2 vs as) but I didn't think that would make as large of a difference. I use an edge pro with the standard stones and then strop on a leather paddle.

Are you sharpening them at the same angle?

[raleighcook15]

I am sharpening at the same angle. I'm thinking maybe ill give it try at a lower grit and then strop. Will test this week and come back. I really only use it as a meat slicing knife and a slicer on the line. I may trade it all together for a slicer

[Cutuu]

By hair splitting are you referring to hanging hair, or are you just using it to express something feeling very sharp?

[raleighcook15]

By hair splitting are you referring to hanging hair, or are you just using it to express something feeling very sharp?

More of hair shaving. It doesn't feel as sharp when I feel the edge. It certainly doesn't cut as well. Chives will spring off the voard perfectly with the yuki, whereas the Kohetsu isn't a clean of a cut.

[Rufus Leaking]

How many times have you sharpened your Kohetsu? It may take a dozen sessions to finally remove all vestiges of the original finish/edge. Mebbe even more using the EP. You may want to invest in the Kohetsu Stones, and use them solely for your AS steel(s).

[Radar53]

The first thing that came to mind for me was that you are using standard stones. With the AS being a harder, tougher & more wear resistant steel, the standard stones are going to really struggle and after a LOT of grinding, that may mean not quite getting to the edge of the edge, or that other mistakes are creeping in. Maybe try & borrow a Shapton Glass 500 (or buy one) and try to cut a great bevel with it. Once that hard lifting is done, you could possibly refine that with an EP 600 or and EP 1000 Even the refining might prove to be somewhat trying.

If you are going to head into the more exotic steels the standard EP stones simply wont cut it (pun intended ) and I would suggest moving to Shapton Glass 500, 1k & 2k

Also remember that the grit rating for the standard EP stone is to a different standard than the standard used for most third party alternatives. eg an EP1200 is equivalent to a Shapton 5k

Just my 2¢ worth

[ken123]

@radar53 + .02

Exactly use better stones.

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Ken

[Bensbites]

This may be a silly question, but is AS harder to deburr than other steels?

[gladius]

There are two factors: edge sharpness and grind.

While AS steel when blacksmith'd well will get very sharp, white steel when done well gets a little bit sharper and easier. With that said the AS should get very very sharp - AS is not that much harder to sharpen than white #2.

• What stones do you have and
• what progression are you using?

The Kohetsu AS is a little more robust knife than the Yuki so will not seem to cut as well, even when equally sharp. The Yuki will go through product easier as it is thinner at and behind the edge.

Compare Kohetsu (left) to the Yuki (right)

[jmcnelly85]

How sharp are you getting your knives early in the progression? It’s amazing what sharpness tests can be passed very early in a progression. My guess is jumping early.

[raleighcook15]

I understand they are different grinds but that shoulf have minimal effect on things like chives. If I were to get Shapton glass, what progression do you suggest. I also have a Matsubara ginsan, and kono hd to sharpen.

[gladius]

I understand they are different grinds but that shoulf have minimal effect on things like chives. If I were to get Shapton glass, what progression do you suggest. I also have a Matsubara ginsan, and kono hd to sharpen.

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SG500 extra-thick, 2k & 8k or 16k

[raleighcook15]

I understand they are different grinds but that shoulf have minimal effect on things like chives. If I were to get Shapton glass, what progression do you suggest. I also have a Matsubara ginsan, and kono hd to sharpen.

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SG500 extra-thick, 2k & 8k or 16k

Is the extra thick needed? Cant find that?

[gladius]

Is the extra thick needed? Cant find that?

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It will be your most used stone and is a good value: double the stone for half more.

https://www.chefknivestogo.com/shglst500grx.html

[raleighcook15]

Is the extra thick needed? Cant find that?

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It will be your most used stone and is a good value: double the stone for half more.

https://www.chefknivestogo.com/shglst500grx.html

I'm looking to stick with edge pro stones.

[gladius]

I'm looking to stick with edge pro stones.

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It looks like Mark is out-of-stock...
Check here:
https://www.jendeindustries.com/index.p ... tones.html
https://www.gritomatic.com/collections/edge-pro-stones

Ken may also carry them.

[Ourorboros]

Some people have raised the point that Kohetsu AS is harder than the Yuki, ~64HRC vs 61 IIRC. But I don't remember if it's been said that you've raised a burr?
So have you checked to make sure you've raised a burr? Because if not, that's obviously what you need to work on. If you can't, you need better stones or softer steels.