M390 carbide tearout? Delica ZDP vs Griptilian?

Which knife for EDC/work?

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Asterisk

Joined
Jan 4, 2019
Messages
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Hey all,

Just wanted to ask a few questions across a topic or two. I've been watching Michael Christy's videos, and recently was exposed to the idea of carbide tearout. I know this is a controversial topic, so going forward let's just act like it is a solidly confirmed fact on this thread.

In my sharpening setup, I have a couple of inexpensive stones. I have a Smith's aluminum oxide 120/240, an inexpensive 600/1200(?) diamond stone, and a 1000/6000 king stone.

My question is, with that setup, do I have to worry about carbide tear out with M390 especially, or really having any issues with sharpening S30V, ZDP, or M390?

Also, on a seperate matter, I would like your opinions on the M390 Link, vs the ZDP Delica, vs the S30V Griptilian for an EDC/work knife. (I live on a farm, and I carry a knife every day, so it's pretty much one and the same for me.) My current EDC is a Steel Will Cutjack in D2, which is great, but I'm not a huge fan of the finger choil. I'm more for a hammer grip.
 
I have the M390 Link, a S30V Griptilian, and a non-ZDP Delica. Of the three, I greatly prefer the Link. It’s mostly because of the handle and blade shape. I don’t have a problem with the aluminum handles being slippery. I sharpen my knives with a Sharpmaker. I don’t normally let them get dull, and I have no experience with carbide tear out.
 
As far as carbide tearout goes, it definitely does happen. It only happens when an edge is sub-3 micron (about 8000 grit) though. Most of the time (for a work knife anyhow), you won't take the edge that fine. Even if it does happen, there is very little difference in edge retention. Basically, it isn't noticeable in use. Go check out SuperSteel Steve's video on it that he posted just before Christy's. He even did a live sharpening and test with it after Christy posted his video. I'm not saying Christy's video is BS, but there's something to be said about doing it live and getting the same results.

For the work knife, it's hard to beat a Griptilian in S30V for the value. Regardless of what everyone says about it, S30V is a great overall steel. Very well balanced. Benchmade is normally really good about their heat treat protocol as well. The ZDP delica is also great and will give you better edge retention for sure. The tradeoff is that it is a bit easier to chip and more difficult to sharpen.
 
When you track the conversation closely, you will note that carbide tear out is said to emerge at a sub 3 micron level. That’s a progression beyond around 8k grit. Short of that point, the carbides are smaller than the cuts from sharpening, and may hide in those cuts. When hidden, you aren’t cutting or tearing out the carbides, anyway.

So... short of about an 8k progression, it is irrelevant.

More relevant... high carbide steels often perform better with more coarse edges, which allow the carbides to do their job.

So, the carbide tear out conversation summarizes like this: “if you throw away performance by progressing these steels too far, you may also find carbide tear out.”
 
Banter 247 said:
When you track the conversation closely, you will note that carbide tear out is said to emerge at a sub 3 micron level. That’s a progression beyond around 8k grit. Short of that point, the carbides are smaller than the cuts from sharpening, and may hide in those cuts. When hidden, you aren’t cutting or tearing out the carbides, anyway.

So... short of about an 8k progression, it is irrelevant.

More relevant... high carbide steels often perform better with more coarse edges, which allow the carbides to do their job.

So, the carbide tear out conversation summarizes like this: “if you throw away performance by progressing these steels too far, you may also find carbide tear out.”
Click to expand...

How coarse of an edge would you recommend for high carbide steels? I will, of course, experiment myself if and when I get any of these, but I would like to know your experience.
 
Banter 247 said:
When you track the conversation closely, you will note that carbide tear out is said to emerge at a sub 3 micron level. That’s a progression beyond around 8k grit. Short of that point, the carbides are smaller than the cuts from sharpening, and may hide in those cuts. When hidden, you aren’t cutting or tearing out the carbides, anyway.

So... short of about an 8k progression, it is irrelevant.

More relevant... high carbide steels often perform better with more coarse edges, which allow the carbides to do their job.

So, the carbide tear out conversation summarizes like this: “if you throw away performance by progressing these steels too far, you may also find carbide tear out.”
Click to expand...

I think we pretty much just summarized each other's posts LOL
 
Asterisk said:
How coarse of an edge would you recommend for high carbide steels? I will, of course, experiment myself if and when I get any of these, but I would like to know your experience.
Click to expand...

I like anywhere from 600 to 1500 or so. It really depends on the steel. Something like M390 is better at 1500 whereas something like S90V is better at 600.
 
Asterisk said:
How coarse of an edge would you recommend for high carbide steels? I will, of course, experiment myself if and when I get any of these, but I would like to know your experience.
Click to expand...

I’m not a “sharpening guy”, in the sense of sweating a specific finish for each steel, and I tend to go with what works well for me at work. In my daily life, I work in a retail/warehouse environment, and I cut a lot of cardboard, plastic packaging, zip ties, and plastic banding straps.

Most of the knives I buy happen to come in S35VN or M390/20CV/204P, because that’s kind of the norm for ti framelocks right now.

So, I set S35VN to 17dps, strop a few passes to 6k, then put on a 20dps, 1k micro bevel. That gives me a wet looking secondary bevel, with a bit of bite at the apex. Looks nice, cuts well.

I’m a simple man.
 
Its best to use diamonds with these steels regardless of carbide tear out that will happen at sub 3 micron if your not using diamonds.

There are a healthy amount of people not going into that range of sharpening. And thus dont get the performance of the steel they even bought. Some steels may perform better at a more coarse grit in cutting different materials. So this can be confusing to some.

I dont forsee any issues with ct with zdp-189 because it does not even have large carbides. But alas i dont have any myself to test this.

The use of diamonds is much faster sharpening and provides a more crisp edge. The diamond is harder than the Vanadium in steel that has large amounts of it. Where ceramic will load up and have to be cleaned often. Diamond just chews and keeps going.

Often times you have people who will be using something else and there edges wont last very long, then switching to diamond and getting far better performance. This could be carbide tear out.

Christies video shows that ct is a thing and shows with a full sharpening how the performance can be had. Steves video shows that you can sharpen okay and get the same performance. Though he's not nearly as good at sharpening. Which reflects the majority of people.
 
Mo2 said:
Its best to use diamonds with these steels regardless of carbide tear out that will happen at sub 3 micron if your not using diamonds.

There are a healthy amount of people not going into that range of sharpening. And thus dont get the performance of the steel they even bought. Some steels may perform better at a more coarse grit in cutting different materials. So this can be confusing to some.

I dont forsee any issues with ct with zdp-189 because it does not even have large carbides. But alas i dont have any myself to test this.

The use of diamonds is much faster sharpening and provides a more crisp edge. The diamond is harder than the Vanadium in steel that has large amounts of it. Where ceramic will load up and have to be cleaned often. Diamond just chews and keeps going.

Often times you have people who will be using something else and there edges wont last very long, then switching to diamond and getting far better performance. This could be carbide tear out.

Christies video shows that ct is a thing and shows with a full sharpening how the performance can be had. Steves video shows that you can sharpen okay and get the same performance. Though he's not nearly as good at sharpening. Which reflects the majority of people.
Click to expand...

Fully agree with 95% of what you said. I definitely think Christy is a better sharpener, but Steve is no slouch. He's way above what 95% of the knife community can sharpen to. You don't think that Christy's results have something to do with the different grits of diamond sprays/emulsions that he puts it through? Or that being provided the sprays by Ken Schwartz plays a part? It just seems a bit fishy that his results were so much different. Steve went back and did it live with an audience and got the same results. I think Christy could put this whole thing to rest if he did the same.
 
tomhosang said:
Fully agree with 95% of what you said. I definitely think Christy is a better sharpener, but Steve is no slouch. He's way above what 95% of the knife community can sharpen to. You don't think that Christy's results have something to do with the different grits of diamond sprays/emulsions that he puts it through? Or that being provided the sprays by Ken Schwartz plays a part? It just seems a bit fishy that his results were so much different. Steve went back and did it live with an audience and got the same results. I think Christy could put this whole thing to rest if he did the same.
Click to expand...
Too much drama Dont read into it like that.
 
tomhosang said:
There is no drama. The only thing I'm looking at is the results. There is no possible way that they can be that different.
Click to expand...
You've seen Christy's vids of him sharpening. You dont need a live to show anything else. Theres nothing else to add.
 
Asterisk said:
How coarse of an edge would you recommend for high carbide steels? I will, of course, experiment myself if and when I get any of these, but I would like to know your experience.
Click to expand...

Your 600 diamond will give you a very durable edge, that will be both sharp and durable.
 
In terms of a very basic beginner just giving their knives with high class steels a touch up (such as 20cv/m390/m4/hap40/cruwear/etc.) on a system such as the sharpmaker, which stones would be best to avoid tear out? Just diamond or CBN? Or could those medium grey looking stones also be added into their sharpening, without tear out?
 
LoveMeSumSpydies said:
In terms of a very basic beginner just giving their knives with high class steels a touch up (such as 20cv/m390/m4/hap40/cruwear/etc.) on a system such as the sharpmaker, which stones would be best to avoid tear out? Just diamond or CBN? Or could those medium grey looking stones also be added into their sharpening, without tear out?
Click to expand...
Anything under three micron you should be fine. Those other abrasives will work. When your sharp maker rods start to load up with black marks, clean them.
 
Mo2 said:
You've seen Christy's vids of him sharpening. You dont need a live to show anything else. Theres nothing else to add.
Click to expand...

Live would prove that he's not messing with the results. All I'm saying is that it seems super fishy.
 
tomhosang said:
Live would prove that he's not messing with the results. All I'm saying is that it seems super fishy.
Click to expand...
Lolol whatever man. Thats the dumbest thing ive heard. If steve made you come to this conclusion, then thats just not right.
 
Mo2 said:
Its best to use diamonds with these steels regardless of carbide tear out that will happen at sub 3 micron if your not using diamonds.

There are a healthy amount of people not going into that range of sharpening. And thus dont get the performance of the steel they even bought. Some steels may perform better at a more coarse grit in cutting different materials. So this can be confusing to some.

I dont forsee any issues with ct with zdp-189 because it does not even have large carbides. But alas i dont have any myself to test this.

The use of diamonds is much faster sharpening and provides a more crisp edge. The diamond is harder than the Vanadium in steel that has large amounts of it. Where ceramic will load up and have to be cleaned often. Diamond just chews and keeps going.

Often times you have people who will be using something else and there edges wont last very long, then switching to diamond and getting far better performance. This could be carbide tear out.

Christies video shows that ct is a thing and shows with a full sharpening how the performance can be had. Steves video shows that you can sharpen okay and get the same performance. Though he's not nearly as good at sharpening. Which reflects the majority of people.
Click to expand...

I highlighted this part because the language may allow for confusion. Different people may read “that range of sharpening” in different ways. It could be received as a comment about a level of sharpening skill, or about a level of applied finish.

To be clear to readers:

1. Carbide tear out in sharpening is specific to high vanadium steels, with 3% or 4% vanadium often being the discussed threshold after which it may happen.

2. Carbide tear out is said to occur once the size of the sharpening cuts are smaller than the size of the vanadium carbides, themselves. This is around 3 micron, or 8k grit.

The discussion of whether or not carbide tear out happens, or about whether alumina or diamond make a difference with it, is a fruitless discussion.

You can run high vanadium steels at grit progressions far lower than 8k and get your money’s worth. The money spent on these steels is spent to put those vanadium carbides to use. Going to more fine finishes with them (let alone 3 micron) seems to be strictly counterproductive.
 
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