The Ignorance of Steel

[Wandering_About]

While I’ve heard and somewhat agree with stopping at 400 grit there seems to be more to the story. One article I read says K390 is a low alloy steel. Is this correct? Mine was fine at 400 grit but a bit better at 600 grit. Then I polished it to 1000 grit and not much difference. After stropping on the Beavercraft green compound it became downright scary and the higher performance was very easy to feel in tougher cutting. Also a polished edge seems to last far longer with less chance of micro chipping. All I can say for sure is I’m very impressed and happy with the steel and that finish on the edge.

K390 is NOT a low alloy steel.

This is the article that I’m definitely questioning.

https://thetruthaboutknives.com/k390-st ... eel-guide/

What I do know is it takes a fine, sharp, durable edge and seems to hold it for a very long time

K390 is very similar to CPM 10V, and these are not low alloy steels. Here's a good article about the "A11" class steels: https://knifesteelnerds.com/2020/08/03/ ... eat-treat/

[Ryder]

While I’ve heard and somewhat agree with stopping at 400 grit there seems to be more to the story. One article I read says K390 is a low alloy steel. Is this correct? Mine was fine at 400 grit but a bit better at 600 grit. Then I polished it to 1000 grit and not much difference. After stropping on the Beavercraft green compound it became downright scary and the higher performance was very easy to feel in tougher cutting. Also a polished edge seems to last far longer with less chance of micro chipping. All I can say for sure is I’m very impressed and happy with the steel and that finish on the edge.

K390 is NOT a low alloy steel.

This is the article that I’m definitely questioning.

https://thetruthaboutknives.com/k390-st ... eel-guide/

What I do know is it takes a fine, sharp, durable edge and seems to hold it for a very long time

K390 is very similar to CPM 10V, and these are not low alloy steels. Here's a good article about the "A11" class steels: https://knifesteelnerds.com/2020/08/03/ ... eat-treat/

I just sent a message to the author of the article and am waiting for a reply on why he calls k390 a low alloyed steel. I’m interested in his response.

I grew up with carbon steels in my knives so am easily taking care of the k390. The more I use it the more I’m impressed.

[Strauss95]

Recently I also became a fan of coarse edges. I still run polished edges on some of my knives, but I used to sharpen every knife I owned up to the highest possible grit. The introduction of these super high vanadium content super steels is what led me to experimenting with coarse edge finishes. I don't run them super coarse, I typically finish in the 400-800 grit range for that type of edge.

I still and always will love the look of a nice polished edge, but in actual EDC use a coarse edge out performs them 90% of the time for me.

[Pete1977]

I have been using coarse edges since the days when Spyderco used ATS-55 and AUS-8. I have never been into super steels and had no problem with the edge retention of H1 or 8CR13MoV. I was cutting a lot of rope that spent a lot of time on the bottom of the ocean and 3 or 4 cuts would dull S30V as quickly as AUS-6. I would tinker with edge angles and grits but found that for hard cutting chores of fibrous materials a coarse toothy edge worked much better than a highly polished edge. While my experience was by no means scientific, i had a lot of it and found I prefer an easy to sharpen with minimal effort steel over mid range or super steels. I recently picked up a Caribbean Salt SE to try out the excellent serration patterns as well as LC200N. Ordinarily I don’t spend this much on a knife I plan to use around water but i still tend to go to my PE tenacious.

When I was a broke commercial fisherman i carried the same Byrd Rescue for about 6 years. I would touch it up on the coarse sharpmaker stones, the diamonds if it was bad. The serrations are mostly worn off by now.
I don’t have much interest in hard highly wear resistant steels and favor toughness over hardness. I like to be able to give a knife a few passes on the sharpmaker to restore a dull edge without having to resort to diamonds.

When I was younger and had money i tried the super steels periodically but always seemed to go back to VG-10 or “lesser” steels. AUS-8 and ATS-55 are still favorites of mine for their ability to take a toothy edge and hold it for a reasonable amount of time and bring it back to a workable level of sharpness in a few minutes.
All of my experience with S30V resulted in edge chipping and VG-10 was difficult to sharpen without diamonds, especially in a serrated knife.

I am lazy, hate sharpening knives, so i lean more towards tougher softer steels. Sometimes in a working knife less is more IMO.

[electro-static]

I have been using coarse edges since the days when Spyderco used ATS-55 and AUS-8. I have never been into super steels and had no problem with the edge retention of H1 or 8CR13MoV. I was cutting a lot of rope that spent a lot of time on the bottom of the ocean and 3 or 4 cuts would dull S30V as quickly as AUS-6. I would tinker with edge angles and grits but found that for hard cutting chores of fibrous materials a coarse toothy edge worked much better than a highly polished edge. While my experience was by no means scientific, i had a lot of it and found I prefer an easy to sharpen with minimal effort steel over mid range or super steels. I recently picked up a Caribbean Salt SE to try out the excellent serration patterns as well as LC200N. Ordinarily I don’t spend this much on a knife I plan to use around water but i still tend to go to my PE tenacious.

When I was a broke commercial fisherman i carried the same Byrd Rescue for about 6 years. I would touch it up on the coarse sharpmaker stones, the diamonds if it was bad. The serrations are mostly worn off by now.
I don’t have much interest in hard highly wear resistant steels and favor toughness over hardness. I like to be able to give a knife a few passes on the sharpmaker to restore a dull edge without having to resort to diamonds.

When I was younger and had money i tried the super steels periodically but always seemed to go back to VG-10 or “lesser” steels. AUS-8 and ATS-55 are still favorites of mine for their ability to take a toothy edge and hold it for a reasonable amount of time and bring it back to a workable level of sharpness in a few minutes.
All of my experience with S30V resulted in edge chipping and VG-10 was difficult to sharpen without diamonds, especially in a serrated knife.

I am lazy, hate sharpening knives, so i lean more towards tougher softer steels. Sometimes in a working knife less is more IMO.

I agree with you on the advantages of simple tough steels, stuff like AUS-8 and 8Cr13MoV gets way too bad a rap when they are really excellent steels for tough jobs. I gave my roomate who is a contractor my byrd cara-cara 2 and he loves the **** thing, and has used it for stripping wires and digging around in the dirt and gravel. The blade has yet to suffer major damage and takes me two mins to bring back on my worksharp field sharpener.

I’m pretty new to sharpening (perhaps 2-3 years), and have only ever used diamond abrasives. For me they were cheaper, easier to maintain and use, and were agnostic to whatever steel I have used on them. Only disadvantage being it’s hard to find them in higher grits. As I use mostly high vanadium PM steels I don’t really want to use finer grits.

From someone who doesn’t like to resort diamonds them what do you not like about them?

[Pete1977]

It is not so much that I don’t want to resort to diamonds, I am just a lazy person who hates sharpening knives lol. I tend to use it until it is dull and then bring it back to a shaving sharp edge. With the non-super steels i can usually accomplish this fairly quickly vs with high wear, harder steels.
For my needs i prefer a tough steel that deforms instead of chipping and takes the minimal amount of time to repair if necessary.
The potential of each steel type can be realized by different edge angles and sharpening grits to maximize its cutting ability. I had to have the latest and greatest steel (S30V) at the time, until i could only afford 8Cr13MoV and then I made due. Between a Byrd Rescue and a Buck Bantam i realized that for even the heaviest duty cutting those steels are fine, especially in knives from reputable companies. I am content with my Tenacious and have carried it for 14 months. This month it will probably take some time off for a Caribbean Salt SE or a Paramilitary 2 PE S30V- more for me to be able to bring myself to use more expensive knives in the field than for any quality issues.

[zhyla]

I’ve been very frustrated with my S30V Positron. Or as I usually refer to it, the Gents Shiv. For whatever reason these have terribly thick grinds so they aren’t slicy in any way. But even still it should sharpen up and cut stuff. But I’ve always had it struggle with even just opening boxes.

I’ve not had that trouble with S30V Spydies at all. But anyway I whipped out a sharpmaker coarse rod and touched up the edge and it sure cuts stuff better now. Pretty odd but glad to have something that works for this blade.

[BeggarSo]

I’ve been very frustrated with my S30V Positron. Or as I usually refer to it, the Gents Shiv. For whatever reason these have terribly thick grinds so they aren’t slicy in any way. But even still it should sharpen up and cut stuff. But I’ve always had it struggle with even just opening boxes.

I’ve not had that trouble with S30V Spydies at all. But anyway I whipped out a sharpmaker coarse rod and touched up the edge and it sure cuts stuff better now. Pretty odd but glad to have something that works for this blade.

The so called coarse brown stones are anything but coarse, coarse by comparison to the white stones yes but thy are actually pretty fine.

Not sure where the fear mongering I used to see about the brown stones taking off too much steel came from but it seriously is not a thing. Reprofile and I mean really reprofile a blade and you will learn just how little steel is truly removed as well as how much work it takes and time.

That being said get the CBN Rods put a sharpie on the edge and then you will certainly get somewhere, After that you can use the brown or the white rods and it will make S30V cut like crazy.

Although I own the sharpmaker I prefer the Spyderco Gauntlet, it will certainly sharpen S30V if you buy the combo package with CBN rods and White rods.

The CBN Rods are what really bring out te best in S30V and quite a few other steels as well.

[zhyla]

Agreed, coarse feels like 400 grit to me.

[Sharp24/7]

I have to say the brown Sharpmaker rods give an excellent finish, and that includes steels like K390 and 15V.

[Bill1170]

I used to feel my edges losing their bite when progressing from brown to white SM rods. Now most of my PE folders get finished on the brown rods.

My Galley-Vee has the 12” white rods and the 9” CBN rods from the Gauntlet. I’m not aware of brown cat eye rods that fit, would get them if I could. I reprofiled an old 6” Henckels kitchen knife to 20 inclusive on the CBN, then did a bit of refining on the white rods. It’s already a thin blade, so it cuts even better now.

[Toucan]

While I’ve heard and somewhat agree with stopping at 400 grit there seems to be more to the story. One article I read says K390 is a low alloy steel. Is this correct? Mine was fine at 400 grit but a bit better at 600 grit. Then I polished it to 1000 grit and not much difference. After stropping on the Beavercraft green compound it became downright scary and the higher performance was very easy to feel in tougher cutting. Also a polished edge seems to last far longer with less chance of micro chipping. All I can say for sure is I’m very impressed and happy with the steel and that finish on the edge.

K390 is NOT a low alloy steel.

This is the article that I’m definitely questioning.

https://thetruthaboutknives.com/k390-st ... eel-guide/

What I do know is it takes a fine, sharp, durable edge and seems to hold it for a very long time

Bohler refers to K390 as "high-alloyed" on their own website. https://www.us.bohler.com/en/products/k390-microclean/

That particular website you linked is really weird.

Lots of little things, like their page for CPM-154 has a S110V Para3 with the branding 'shopped off as its header image. Their review of a Kephart knife uses a stock photo of a kitchen knife and says the knife is made in a particular steel and hardness despite not listing a make or model using the Kephart pattern. Then for some reason there's a review for the Sword of Goujian

It seems possible that it is a machine generated website for clicks. Most of the information and photos seem like they were scraped from other sites. It would explain some of the incoherence like referring to a pattern of knife as if it were a specific model and using an unrelated picture. Or having a review for a 2500 year old sword. I wouldn't rely on any information gleaned from that website.

[vivi]

I think most people, myself included, fall in love with polished edges when they get into nice knives and sharpening.

Being able to push cut through things is fun, especially when you're used to dull edges that require a sawing motion.

But over the years I made a lot of observations that led me away from polished edges.

The first step in my journey was leaving bevels course and polishing just the apex, an idea I got from Gunmike1. Cutting performance is equal to a fully polished bevel but the edge can be applied in 1/4 the time or less. I kind of cringe when I see fully polished bevels on users because I know the person that applied it wasted a lot of time just for aesthetics.

Eventually I started keeping the apex coarse too. Cliff Stamp has championed the idea for years but I wasn't convinced it was the optimal way to sharpen until I tried it myself.

I took my oldest PE Aqua Salt and experimented. I tried going from UF rods to F, then F to M, then eventually I learned to get shaving sharp edges off my coarsest stone, a DMT X Coarse.

There are so many benefits to the coarse PE sharpening method. Saves time, increases edge retention, saves money, etc.

Last night I touched up my PE Resilience. All I used was the 300 grit side of my $12 4 sided diamond stone from harbor freight. Shaving sharp in 45 seconds. Slices like a beast. It'll outcut S30V taken to a fine sharpmaker rod polish on cardboard easily. No strops, no oil, no guided rigs - just a single dry diamond plate. I can maintain all my PE pocket knives with that single $12 stone.

I've heard a lot of people talk about how X steel likes a polished edge or Y steel works better with a toothy edge. Personally I think any steel can take any type of edge, some just require more work than others.

It's an eye opening process trying all these different edges on different steels and cutting tools. I've tried 80-4,000 grit edges on machetes, axes, 10" sujihikis, Victorinox Classics, etc. I think a lot of the sharpening knowledge out there is wrong.

For example most suggest coarse edges for axes, but they're push cutting tools so I take them to a high polish. Everyone knows chef knives should have a high polish edge, but I prefer a 300 grit edge stropped a few times on my main gyuto, a 10" super blue from tsunehisa. It works better for cutting steaks, prepping veggies, etc. That said I keep a 4,000 grit edged 8" gyuto in my knife roll too but it's very rare I reach for it.

Another is edge angles. I see a lot of posts here along the lines of "do you think x spyderco can handle a 15 dps edge?" and I laugh. I've taken spydies down to 5 degrees per side and had them work just fine.

This is a topic I could write pages on. The best advice I can give anyone new to sharpening is experiment, experiment, experiment.

[Stuart Ackerman]

I like toothy edges, as you might guess?

As Vivi says, experimentation is the spice of life...

[Sharp24/7]

I’d mirrored several knives and the cutting performance had degraded quickly, no aggression, so I touched up on the Sharpmaker stones because I remembered someone on here mentioning that they leave a toothy finish. The white stones were okay, but the brown gave a seriously nice edge. Since I set the bevels on my Edge Pro, the SM stones left a slight microbevel, so I seem to have the best of both worlds.
The apex grabs but the polished bevels seem to help the knife glide through the material. Of course, I’ve only been rocking that edge type for a week, so I’ll have to see how it holds up.