# Blade geometry and thickness



## mark76 (Dec 16, 2013)

Recently I got a thickness gauge. I've used it to measure a couple of kitchen knives. The results surprised me a bit. More about that below.

I measured the following knives:
- Richmond Artifex 210 mm chef knife, convexed by Tim Johnson
- Suisin Inox Honyaki 210 mm chef knife
- Fujiwara 240 mm chef knife
- Takeda 270 mm yanagiba (actually a sujihiki, it is double-bevelled)
- Zwilling Four Star 200 mm chef knife

I measured the knives in three places:
(1) At the spine, where the blade starts
(2) At the spine, near the tip
(3) Half a centimeter above the edge, halfway the blade

The measurement results are the following.


```
Thickness in mm
                     (1)      (2)      (3)
Artifex              2.5      0.6      0.7
Suisin               2.3      0.5      0.6
Fujiwara             2.2      0.6      0.6 
Takeda               2.4      0.5      1.2
Zwilling             3.6      0.6      0.7
```

What surprises me is that the measurements for "high end" knives (Suisin, Takeda) are so close to those of "less high end" knives (Fujiwara, Zwilling, maybe Artifex). In fact, all of them are 0.5 mm or 0.6 mm thick at the tip (2). 

Also, all of them are 0.6 mm or 0.7 mm thick just behind the edge (3). The only exception is the Takeda with 1.2 mm, whereas this is perhaps the most highly regarded knife.

There is slightly more variation in the thickness at the spine, where the blade starts (1), but here the thinnest knife is the second-cheapest, the Fujiwara.

This leaves me a bit confused about the relationship between how highly regarded a knife is as a cutter and its thinness. I thought that the best cutters would also be the thinnest, particularly just behind the edge.

But apparently this is not the case. What are your thoughts?


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## CoqaVin (Dec 16, 2013)

I have a Fujiwara and it is light as hell only seems to wedge on a tough carrot


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## tripleq (Dec 16, 2013)

A lot more than thinness determines how well a knife will cut. Spot measurements don't always tell the whole story. In knife geometry the sum of the parts are often less than or greater than the whole. There is also the aspect of technique and personal preference. Some people favor maker x while others dislike the same knife. Keep in mind that some people don't even like very thin or 'laser' knives. I have a few lasers that I don't touch anymore. They are paper thin but the overall grind doesn't make sense to me. Some of my best cutters are actually quite thick.


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## cheezit (Dec 16, 2013)

Based on your experience, which of those knives is your best cutter?


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## Timthebeaver (Dec 16, 2013)

tripleq said:


> A lot more than thinness determines how well a knife will cut. Spot measurements don't always tell the whole story. In knife geometry the sum of the parts are often less than or greater than the whole.



+1


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## brainsausage (Dec 16, 2013)

The grind tells the real story. Pinch the blade face about halfway up with your thumb and index finger, with the edge facing your palm, and then pull towards the edge. Do this across the majority of the blade face, and it well tell you a lot about the grind. Kudos to JohnnyChance for teaching me this during a sharpening session last spring. With practice it can be informative.


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## aaamax (Dec 16, 2013)

My best blade is an old Watanabe 270 Gyuto.
At the spine it's a wopping 4mm, mid way down spine 3, top of choil 3mm with a face of 6.8 cm.
This aint no ballerina, more like a German barmaid. But daaaaamn can she cut the eyeballs out of a termite.


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## mark76 (Dec 17, 2013)

Cheezit: I guess both the Suisin and the Artifex are my favourites: they seem to cut the best. That said, the Fujiwara and the Zwilling cut very well too, properly sharpened.

Brainsausage: what exactly do you mean by the ground telling the real story? Do you like very well polished blades? Or convex grinds? Or ...

Everyone else: also interested in your opinions/experiences! Why is the Suisin Inox Honyaki so much more highly regarded than the Artifex, whereas their thicknesses in all places are nearly the same? And why is the Takeda regarded so highly? It is by far the thickest behind the edge.


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## JDA_NC (Dec 17, 2013)

mark76 said:


> Everyone else: also interested in your opinions/experiences! Why is the Suisin Inox Honyaki so much more highly regarded than the Artifex, whereas their thicknesses in all places are nearly the same? And why is the Takeda regarded so highly? It is by far the thickest behind the edge.



As some are already saying, these numbers can't tell the whole story about a knife.

I don't own a Suisin IH or a Takeda -- or any of these exact knives - so I couldn't tell you. Do you see no difference between the Suisin and Artifex when it comes to weight, balance, fit & finish, food release, edge retention etc? How much work was put in on your Artifex - is it noticeably thinner than originally?

How does your Takeda suji perform? Are you unhappy with it?

I own an Artifex 270mm suji and I actually think the knife is a good deal for what it is. It takes a really fine, acute edge and holds it for a very long time. I know people here are not fond of the brand - and that's another issue - but the steel is, in my experience, pretty darn good. My only real issue with it is that it is actually TOO thin - causing it to have more flex than I'd like. If I'm portioning big, tough cuts of meat, like I do - I prefer something with a bit more heft/stiffness. That's why I bought a new, san-mai, noticeably thicker 270mm suji from JKI. 

That might have something to do with your Takeda's numbers. But what is your experience with it?


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## Timthebeaver (Dec 17, 2013)

JDA_NC said:


> How much work was put in on your Artifex - is it noticeably thinner than originally?




If it was anything like this Artifex (i.e. an utter dog with one of the most pathetic grinds I've seen on a "gyuto"), then enough work to make it completely unrecognisable from stock form, and render any comparison to an SIH utterly meaningless.

http://www.kitchenknifeforums.com/s...n-vs-Forschner?p=213536&viewfull=1#post213536


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## lucabrasi (Dec 17, 2013)

From pictures I've seen Tim J thins them out a lot, and does a great job doing so, so I imagine that has a lot to do with its performance relative to your Suisin. 

I have an artifex tall that was ok, but by no means a laser like cutter out of the box. It's geometry was nothing at all like the one shown in that other thread cited, but still a bit on the thick side. I would guess a tiny bit thicker than a Fujiwara fkm. 

It has greatly improved with substantial thinning and I love using it. Partly because I've enjoyed putting the work into it, makes it really feel like mine.

As others are saying here I don't believe these dimensions really tell the story on what makes a good knife. If all it took was super thin geometry there would be a lot more great knives out there. Seems like there is quite a bit more that goes into making a knife a great performer.


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