Thread: Complex grinds?

So I have been looking to get some nicer kitchen knives lately and am looking more towards some japanese steel knives. Some of the descriptions on some of these knives are mentioning how the "complex grinds on this knife are really great". What would they mean by that. I am not really familiar with knives too much.

Originally Posted by cosperryan

So I have been looking to get some nicer kitchen knives lately and am looking more towards some japanese steel knives. Some of the descriptions on some of these knives are mentioning how the "complex grinds on this knife are really great". What would they mean by that. I am not really familiar with knives too much.

I don't know about complex grinds, but I live in Japan, and I own some very nice, inexpensive "rustic" stye knives I purchased at a large Japanese "big box" store. All made in Japan of course, and they come in varying grades of finish and appearance, I prefer the simple, high carbon steel type. There is a shape of knife for every purpose here. One blade shape for cutting noodles, one for cutting broccoli/cauliflower, one for slicing meat, another for sashimi, etc etc. I have never paid over $50 for one, and I did buy one which seems not too useful, more like a machete.

Originally Posted by cosperryan

So I have been looking to get some nicer kitchen knives lately and am looking more towards some japanese steel knives. Some of the descriptions on some of these knives are mentioning how the "complex grinds on this knife are really great". What would they mean by that. I am not really familiar with knives too much.

If you could give an example I may be able to help further but most makers have there own particular geometry for their kitchen knives and the varieties are endless!

The best grind in my experience is a knife that is very thin immediately behind the edge but still has some heft at the spine. I also prefer a slightly convex grind (think axe but much thinner) as food is less likely to stick to the blade than on a flat ground knife.

Hope this helps a little

The grind looks like this:



pretty interesting to sharpen on stones as well.

That type of grind is used on traditional knives, gyoto and standard double bevel knives use standard symmetric grind.

This is the exact knife that I am curious about. It is a funayaki. I am guessing that it is a double bevel as it says its from the Tosa Region. So if it is double bevel then what is the complex grind? I know about the single bevel knives and they're interesting grinds and was looking at a couple of single bevel funayakis as well.

Edit: Forgot to add the link.
http://www.chefknivestogo.com/tskakufu16.html

Originally Posted by cosperryan

This is the exact knife that I am curious about. It is a funayaki. I am guessing that it is a double bevel as it says its from the Tosa Region. So if it is double bevel then what is the complex grind? I know about the single bevel knives and they're interesting grinds and was looking at a couple of single bevel funayakis as well.

Edit: Forgot to add the link.
Kajiwara Kurouchi Funayaki 165mm

The description says it is a single bevel knife, so it should have the above posted grind geometry.
Those grinds are tricky to sharpen keep that in mind if you are new to single bevel Japanese knives.

Originally Posted by mainaman

The description says it is a single bevel knife, so it should have the above posted grind geometry.
Those grinds are tricky to sharpen keep that in mind if you are new to single bevel Japanese knives.

"In the Tosa region it became common to give the knives a double bevel and use them as a gyuto would be used. As Kajiwara-san resides in Tosa, his rendition of the funayaki follows in the Tosa tradition"

That right there makes me think it is a double bevel.

With the single bevel knives, a lot of them have a tiny secondary bevel on the "flat' side. Also, the convex "transition" can sometimes be the entire blade rode, albeit a VERY shallow convex. Likewise, some double bevel "western" style knives like gyutos, sujihikis and petty can have varying asymmetrical grinds right down at the edge.

Originally Posted by mainaman

The grind looks like this:



pretty interesting to sharpen on stones as well.

That type of grind is used on traditional knives, gyoto and standard double bevel knives use standard symmetric grind.

Originally Posted by JDM61

With the single bevel knives, a lot of them have a tiny secondary bevel on the "flat' side. Also, the convex "transition" can sometimes be the entire blade rode, albeit a VERY shallow convex. Likewise, some double bevel "western" style knives like gyutos, sujihikis and petty can have varying asymmetrical grinds right down at the edge.

Which side is the "flat" side?
From your post I take it you have sharpened knives with that geometry, and have experience with a lot of Japanese kitchen knives?


You must then know that there is no flat side on a traditional knife. Western style knives are symmetrical with exception of Aritsugo gyutos which are intentionally ground asymmetric (back side almost flat). The asymmetry is done post purchase by people that think thin knife cuts better and having no clue how food release works and that a lot of smiths do not know how to grind a proper cutting knife.

Sorry, The "urasuki" side on those knives that actually have the hollow ground into them. As for the "asymmetry" I was talking about stuff like a 60/40. etc primary bevel. The "complex grinds" that I have done are what some would call an "S" grind.

Originally Posted by mainaman

Which side is the "flat" side?
From your post I take it you have sharpened knives with that geometry, and have experience with a lot of Japanese kitchen knives?


You must then know that there is no flat side on a traditional knife. Western style knives are symmetrical with exception of Aritsugo gyutos which are intentionally ground asymmetric (back side almost flat). The asymmetry is done post purchase by people that think thin knife cuts better and having no clue how food release works and that a lot of smiths do not know how to grind a proper cutting knife.