Some experts' opinion for choil shot analysis, please

Kitchen Knife Forums

Help Support Kitchen Knife Forums:

Joined
Nov 5, 2016
Messages
382
Reaction score
343
Location
Germany
[TLDR]: Please take a look at the choil shots and tell me if I'm right in the assumption that the two gyutos are thicker behind the edge which changes their cutting feel.

Hi guys,

I wonder why two new knives I got don't exactly perform as I was expecting. Please note that this is not a criticism of the knives, which certainly are great, but an attempt to understand some of the finer points of knife geometry and performance.

The knives in question are two MCX Honyaki Gyutos which I recently got. One by Spare, one by Isasmedjan. Both are very well-made knives, it shows in every detail. But with denser vegetables, they don't go through as easily as my two most used knives are going through. These two are a Denka Nakiri and a Togashi K-Gyuto.

So, what's my point? For most cooking tasks, they perform very close to each other.

But it's with denser vegetables that the two Gyutos don't go through nearly as easily as I would have thought. I do a lot of julienned carrots, and here they require more pressure to go thorugh than I'm used to. Which is especially not ideal when you have stacked the layers. I think it's fair to rule out sharpness per se, I can elaborate if you want details. I sharpened them all on a 1000 Bester with a one-side refinement on a Rika 5k.

I don't think it's due to knife type - the Togashi isn't a nakiri, after all. Actually, it's more substantial at the shoulders than the Isas, but I think it is much thinner behind the edge. So I took out the macro and made some choil shots. And since it's fun, some knife porno with closeups from the logos.

Can you check if the first two knives are indeed thinner behind the edge to an extent that explain the difference in behavior? Please note that the perspective is different, I was closer to the first two knives. That can warp the impression when comparing them directly.

1. Denka Nakiri.

4H2A3759.jpg
4H2A3764.jpg


Togashi Shirogami K-Tip Gyuto

4H2A3768.jpg


4H2A3770.jpg


Spare Honyaki: Less easy-going than the others, but still quite good.
4H2A3824.jpg
4H2A3784.jpg



Isas Honyaki. This one just doesn't do it for me really with dense vegetables.

4H2A3773.jpg


4H2A3774.jpg
 

tostadas

Senior Member
Joined
Jan 27, 2020
Messages
2,716
Reaction score
5,726
Location
California
Two things really contribute to performance through dense produce like apples, onions, root veggies. Those would be thickness (wedging) , and surface finish (drag).

For thickness, you can look at the knife thickness at various points behind the edge, and get a decent idea of how it will perform. Based on my data points from almost 100 knives, here's how I categorize.

Distance behind edge at midpointThinMediumThick
1mm0.2mm0.25mm0.3mm
5mm0.5mm0.7mm0.9mm
10mm1.0mm1.25mm1.5mm
20mm1.4mm1.7mm1.9mm

Choil shots can sometimes be deceiving because they really only show what it looks like right at the heel. Makers don't always grind consistently along the edge, so the thickness at the heel is not necessarily the thickness at the point where u are actually cutting. Calipers are your friend here, or with some experience you can feel it between your fingertips.
 

Delat

Dazed & Confused
KKF Supporting Member
Joined
Dec 31, 2020
Messages
1,427
Reaction score
2,998
Location
Phoenix
Two things really contribute to performance through dense produce like apples, onions, root veggies. Those would be thickness (wedging) , and surface finish (drag).

For thickness, you can look at the knife thickness at various points behind the edge, and get a decent idea of how it will perform. Based on my data points from almost 100 knives, here's how I categorize.

Distance behind edge at midpointThinMediumThick
1mm0.2mm0.25mm0.3mm
5mm0.5mm0.7mm0.9mm
10mm1.0mm1.25mm1.5mm
20mm1.4mm1.7mm1.9mm

Choil shots can sometimes be deceiving because they really only show what it looks like right at the heel. Makers don't always grind consistently along the edge, so the thickness at the heel is not necessarily the thickness at the point where u are actually cutting. Calipers are your friend here, or with some experience you can feel it between your fingertips.

Agree with measuring at several points. I generally like my knives about .1mm @1mm and <.5 @5mm, but tbh it’s really hard to get repeatable measurements. Which is to say it’s probably just operator variance between my measured preference and what @tostadas shared above.

My experience with an early Spare MCX drop was that it was more of a midweight in terms of performance, a bit thicker BTE than I personally like. The latest Spare MCX (bunka) is a bit thinner, so he’s refined his grind a bit. It’s skirting the borderline for me to where I can’t decide if I should thin it or not, whereas if I’d kept my first MCX I would’ve definitely thinned it.
 

tostadas

Senior Member
Joined
Jan 27, 2020
Messages
2,716
Reaction score
5,726
Location
California
Agree with measuring at several points. I generally like my knives about .1mm @1mm and <.5 @5mm, but tbh it’s really hard to get repeatable measurements. Which is to say it’s probably just operator variance between my measured preference and what @tostadas shared above.

My experience with an early Spare MCX drop was that it was more of a midweight in terms of performance, a bit thicker BTE than I personally like. The latest Spare MCX (bunka) is a bit thinner, so he’s refined his grind a bit. It’s skirting the borderline for me to where I can’t decide if I should thin it or not, whereas if I’d kept my first MCX I would’ve definitely thinned it.
My mxc was 0.25/0.7/1.1/1.7mm @1/5/10/20mm behind the edge at midpoint. And performed as expected for that thickness which is to say middle of the road on dense veg
 
Joined
Nov 5, 2016
Messages
382
Reaction score
343
Location
Germany
Thanks a lot @Delat and @tostadas for the info. Might be a fun little thing to get a device to measure this :)

Interesting thing about the Isas gyuto.. i mean it's by far the most expensive of the three knives, and fit and finish are meticulous in every detail. I assume that it got several times the finishing time than the Denka for example. So there certainly is a good reason why it is made this way exactly. Because at the spine it is actually the thinnest of all the knives. It's 186g at 245mm, while the Togashi is 210g at 230mm. MC describes it as "a perfect Walkschliff". I'm not entirely sure what that means in that context.

Maybe it's to make it more an allround knife for meat etc? I'm not cutting meat, so maybe my preferences are for veggieknives. Not sure if I have the nerve to really try and reconfigure the whole geometry of such a well-made and expensive knife though. We'll see...
 
Joined
Jun 6, 2019
Messages
606
Reaction score
1,494
Location
Utah
Thanks a lot @Delat and @tostadas for the info. Might be a fun little thing to get a device to measure this :)

Interesting thing about the Isas gyuto.. i mean it's by far the most expensive of the three knives, and fit and finish are meticulous in every detail. I assume that it got several times the finishing time than the Denka for example. So there certainly is a good reason why it is made this way exactly. Because at the spine it is actually the thinnest of all the knives. It's 186g at 245mm, while the Togashi is 210g at 230mm. MC describes it as "a perfect Walkschliff". I'm not entirely sure what that means in that context.

Maybe it's to make it more an allround knife for meat etc? I'm not cutting meat, so maybe my preferences are for veggieknives. Not sure if I have the nerve to really try and reconfigure the whole geometry of such a well-made and expensive knife though. We'll see...

FWIW the Isas I had a while ago was similar to what you're describing. Felt really solid in hand, wanted to like it, but it was not a dense veg winner by any stretch.
 

Jason183

Senior Member
Joined
Jun 11, 2020
Messages
675
Reaction score
688
Location
United Stats
High thin hollow grind with rough finish and not too thick at the spine is good on cutting tall carrots IME.

The Denka(low hollow) and Togashi(mid hollow) I think they both are sharpened with giant wheel grinders, which most Japanese sharpener do, it creates slight concave grind near the very cutting edge , thus looks more thinner compared to belt grinder.

Knives with robust, more meat behind the cutting edge better on tougher/abusive tasks.
 

myguidingmoonlight

Well-Known Member
Joined
Dec 15, 2021
Messages
169
Reaction score
257
Location
Toronto
I noticed that the primary bevels on these knives are pretty large and noticable, that might be what is affecting performance?
 
Joined
Nov 5, 2016
Messages
382
Reaction score
343
Location
Germany
I noticed that the primary bevels on these knives are pretty large and noticable, that might be what is affecting performance?
Hmm, maybe. I only can really see in on the Spare gyuto, but it might be due to an irregularity in sharpening close to the heel. The knife performs pretty similarly left-and right-handed, so it should be much less asymmetrical than it appears in the picture.

(I'm learning to cut with the right hand, too, since a few of my favorite knives are not so good with the left hand).
 

tostadas

Senior Member
Joined
Jan 27, 2020
Messages
2,716
Reaction score
5,726
Location
California
I noticed that the primary bevels on these knives are pretty large and noticable, that might be what is affecting performance?
Width of primary bevel on its own is not really a good indicator. It can be wide due to thick blade (suggesting thicker) , or because of sharpening at a low angle (suggesting thinner) , or some combination of the two.
 

JayS20

Senior Member
Joined
Feb 9, 2020
Messages
460
Reaction score
954
Location
Germany
Looking at the slightly uneven grinds at the heel of the Togashi and Denka I assume they are even thinner in front than they look like on choil shots which already look slightly thinner than both MCX. Togashi is rather flat ground with high shoulders. Denka Nakiri looks nearly concave on the right sideabove the edge. The Spare and Isasmedjan are convex. So they are thicker in the first 10mm above the edge which are pretty much the most important for an easy cutting.
A Walkschliff means a full convex grind from spine to edge. The thickest point will usually be 5 to 10mm under the spine, the spine is slightly thinner.

My experience with an early Spare MCX drop was that it was more of a midweight in terms of performance, a bit thicker BTE than I personally like. The latest Spare MCX (bunka) is a bit thinner, so he’s refined his grind a bit.
Spare are indeed best described as midweights imo. They are slightly convex, have some weight but not heavy and well balanced. You have to remember that the MCX aren't customs for you but are provided to a bigger audience so I think MCX ordered them slightly thicker behind the edge. Probably after getting feedback regarding this and knowing who his customers are they changed them slightly. Therefore the newer ones are thinner but Fredrik didn't really refine his grinds in general but just on the product. I have 3 custom Gyutos by Fredrik and they are decently thin enough behind the edge, carrots and celery root are not a problem and they are onion killers.
 
Joined
Nov 5, 2016
Messages
382
Reaction score
343
Location
Germany
Very insightful, thanks a lot Jay! Yeah I see what you mean there. I mean, the other two weren't custom either, but especially the Togashi is super thin behind the edge - there is so much core exposed!
I can think about it now what I'm going to do. I want to underline that this is not a criticism in the knives per se, both of them are very well done and great tools as well as pieces of art. But I have learned that I will in the future look more towards thinness behind the edge. Once Frederik has open slots for orders again, I might talk to him about it, because in every other aspect, I adore this knife!
 

M1k3

"Gigantoku" is just code for "Serbian Cleaver"
Joined
Jul 28, 2018
Messages
8,420
Reaction score
13,670
Another thing to consider, the flatter the faces of the knife, the more friction there'll be when cutting dense food.
 

sled_god

Member
Joined
Feb 12, 2021
Messages
14
Reaction score
7
Location
Earth
You could also buy a pair of calipers to really help you tell the thickness. Looking at pictures like that is mostly guesswork.
 
Joined
Nov 5, 2016
Messages
382
Reaction score
343
Location
Germany
That Spare Honyaki is definetly thicker at the edge than his more recent knives, which could contribute alot towards cutting feel.
It is significantly thinner BTE than the isas though. Probably also since its not a Walkschliff but a wide bevel.

This should make it easier to thin it out since I won't be changing the whole geometry.
 

Gregmega

Senior Member
Joined
Apr 12, 2017
Messages
1,655
Reaction score
2,886
Location
Los Angeles
Yeah unfortunately just the choil shot doesn’t tell the whole story. It’s really more about the cross-sectional geometry along the blade road, Jon and I have had endless discussions about this, choil shots are like judging how fast a car can go by inspecting its paint color imo. Fun to look at but has no bearing on performance.
 
Joined
Nov 5, 2016
Messages
382
Reaction score
343
Location
Germany
Yeah i guess that's what it depends on whether a choil shot is a reliable source of info: Is the heel ground the same than the rest of the blade? If it is, then it should be helpful to a degree. But I'll see about those calipers and report back with some measurements :)
 

myguidingmoonlight

Well-Known Member
Joined
Dec 15, 2021
Messages
169
Reaction score
257
Location
Toronto
Yeah i guess that's what it depends on whether a choil shot is a reliable source of info: Is the heel ground the same than the rest of the blade? If it is, then it should be helpful to a degree. But I'll see about those calipers and report back with some measurements :)
I guess in wide bevel blades without a lot of taper, the choil shot would be a good indicator of performance for the rest of the blade. Assuming there's no overgrind at the heel.
 

Benuser

from The Netherlands, EU.
KKF Supporting Member
Joined
May 3, 2011
Messages
8,534
Reaction score
3,207
It's common, easier, and possible to grind the choil thinner than the rest of the blade. You can feel with your fingers if you don't have calipers. That's been the main thing for me . . . along with edge angle
Is it that common? Have seen a lot of knives with an abrupt thickening at the choil.
 

sled_god

Member
Joined
Feb 12, 2021
Messages
14
Reaction score
7
Location
Earth
Choil shots are just porn. The only way the could begin to approach anything meaningful is if they were taken with the same camera, from the exact same distance, the exact same angle, the exact same lighting, same camera settings,
 

Jeezy

Well-Known Member
Joined
Aug 29, 2020
Messages
47
Reaction score
68
Location
Germany
Hey, i know its off topic but is this a 165 or 195 Denka Nakiri ? I would love to buy a 180 TF Nakiri but they dont produce them 😭Can't decide between 165 and 195, its such a huge difference. I might buy a Toyama instead.
 
Top