water stones-razor vs kitchen.

[JDM61]

Are there any differences between the commonly available synthetic water stones you guys use and the ones that you would use for sharpening Japanese kitchen knives?

[mainaman]

Not that I am aware of. The lines commonly used are Chosera, Shapton Glass/Pro, Super stones. People do not use Nortons for knives AFAIK
For razors I do my rough work in Sigma Power 400. Also have 1000k soft and hard, they all work. For me it is a matter of what I feel works best for razors and it is a mix of several brands.
For kitchen knives I use J-nats most of the time now.

[onimaru55]

You can grind/sharpen a knife on any stone but the cosmetic finishing requires the stone to match the steel.
Jnats of a softer nature are best for that. Hard Jnats are traditionally used for razors but slightly softer stones are easier to learn on.

I know one stone seller who grades his Jnats as knife, tool, or razor stones.

As for synthetics the King stones are very popular in Japan for hochou.

[JDM61]

I have a 2 sided King now in 1000/8000, but i suspect that will be temporary.

[onimaru55]

I used a set of Kings on razors for a couple of years. Not the ideal for large volume work but quite ok as far as edges go.

[Vasilis]

Are there any differences between the commonly available synthetic water stones you guys use and the ones that you would use for sharpening Japanese kitchen knives?

The problem with sharpening Japanese kitchen knives, assuming that you are referring to the traditional kind, is, it's hard as heck! You need a lot of experience to hone one, and there are so many types because each performs a different task and need to be honed in a different way, with a bigger or smaller angle. Also, many if not most of them, have a curved shinogi line (sorry guys, sword terms) which you have to follow precisely or it will start to look awful in the long-term. And, if it's flat/hollowed on one side, you have to be careful not to remove more metal than the absolutely necessary.
YouTube videos make it look like a walk in the park, but no matter how many you watch, it won't help you one bit, the methods vary a lot, and no matter how master is the "master" toishi who performs the task, there is more to it than a simple demonstration. You can try, and it will cut, but in the long term, changes on it's anatomy will appear.
Unless the knife you have is a western "chef" like type made in Japan. Santoku, gyuto and any other of this family can be treated pretty much like a chef's knife.
Not knowing what stone to use I presumed that you probably haven't honed one, or spend enough time honing them. If you have, I apologize.

But in any case, there are no specialized stones. Know what grit you need by the condition of your edge, and hone it with any quality stone you have.
Any brand of stone that can be used on a razor can also be used on a knife. And, as always, after you finish a knife, make sure your stone is flat or you'll damage your razors. And, don't try very hard naturals. Hard and very slow/fine natural stones are not worth the effort.
I like the king 1k for knives, and in most cases you don't have to go higher. It offers a nice "hadori" like finish, and cut sufficiently good. The 8k, I'm not familiar with it but it should work nicely too.
In any case, good luck

[mainaman]

The problem with sharpening Japanese kitchen knives, assuming that you are referring to the traditional kind, is, it's hard as heck! You need a lot of experience to hone one, and there are so many types because each performs a different task and need to be honed in a different way, with a bigger or smaller angle. Also, many if not most of them, have a curved shinogi line (sorry guys, sword terms) which you have to follow precisely or it will start to look awful in the long-term. And, if it's flat/hollowed on one side, you have to be careful not to remove more metal than the absolutely necessary.
YouTube videos make it look like a walk in the park, but no matter how many you watch, it won't help you one bit, the methods vary a lot, and no matter how master is the "master" toishi who performs the task, there is more to it than a simple demonstration. You can try, and it will cut, but in the long term, changes on it's anatomy will appear.
Unless the knife you have is a western "chef" like type made in Japan. Santoku, gyuto and any other of this family can be treated pretty much like a chef's knife.
Not knowing what stone to use I presumed that you probably haven't honed one, or spend enough time honing them. If you have, I apologize.

But in any case, there are no specialized stones. Know what grit you need by the condition of your edge, and hone it with any quality stone you have.
Any brand of stone that can be used on a razor can also be used on a knife. And, as always, after you finish a knife, make sure your stone is flat or you'll damage your razors. And, don't try very hard naturals. Hard and very slow/fine natural stones are not worth the effort.
I like the king 1k for knives, and in most cases you don't have to go higher. It offers a nice "hadori" like finish, and cut sufficiently good. The 8k, I'm not familiar with it but it should work nicely too.
In any case, good luck

I do not think sharpening traditional Japanse knives is that hard. There is technique involved but in general nothing demanding. The stones are more important IMHO. Softer muddier stones = even finish.

[Vasilis]

Indeed, the finish looks A LOT better with softer stones, that's why I like the king 1k and old red suehiro 1k. But I don't think the finish is more even. It only looks that way, the scratches look more uniform.
It's not hard to make them sharp, the hard part is keeping them looking like new after 10 years of continuous use, which I think is as important as the knife being sharp.

[mainaman]

Indeed, the finish looks A LOT better with softer stones, that's why I like the king 1k and old red suehiro 1k. But I don't think the finish is more even. It only looks that way, the scratches look more uniform.
It's not hard to make them sharp, the hard part is keeping them looking like new after 10 years of continuous use, which I think is as important as the knife being sharp.

If one wants to do a quick and dirty job, just use uchigumori, or even plain slurry on a rag/paper towel. With practice the finish can be achieved on a the stones exclusively, but it takes time to master. This also is not too practical since it is irrelevant for food cutting IMHO.

[DaveW]

Like above, softer stones for knives. Finish on something like a suita (which is comparable to any softer tomae type stone) on naturals. Provides a very sharp edge on hard steel, but one that looks even finish wise and doesn't look bright with a bunch of cobweb scratches all over it. The bullet hard razor stones that are popular right now don't have the right feel for a knife, and they don't self slurry.

For synthetics, same thing. i don't particularly care for a super bright uniform polish that is the craze right now on a lot of the powder metal and modern steel knives.

I actually sharpen all of my knives on a tri hone right now, using two generally, a fine india and a hard ark, and then strop the knife on leather. That includes two run of the mill japanese knives - one in blue #2 and another in VG 10 stainless. If I am so motivated, I will work the japanese knives on a suita from time to time, because it is the only large fine stone I have that will slurry a little bit on its own.

I'd rather sharpen these knives on a king 8k or one of the softer stones than a shapton. Chosera 10k only if soaked, but like I said, I don't have much of an appreciation for a bright polished bevel on a knife. I think it looks garish and it suggests playing or fiddling to get a visual finish vs. a good sharp working edge.