Really liking S90V

[Spyderwebs]

How does S90V respond to the Spyderco ultra fine ceramics?

It's not going to be as sharp as it could be compared to if you use diamond or cBN..

Excellent info here. Thank you for sharing the science behind sharpening such as tidbits like this.
Looks like I need some harder stones. The UF sharpmaker stones do nice for touch ups, but good to know the first real reprofiling needs cbn or diamond

[p_atrick]

It's not going to be as sharp as it could be compared to if you use diamond or cBN.


The hardness of the ceramic abrasive is 79rc
The hardness of the chromium carbide in S90V is 81rc
The hardness of the vanadium carbide in S90V is 87rc
The hardness of cBN and diamond is 94 and 100rc respectively.
...

Shawn, thanks for the numbers. It really puts it into perspective. Out of curiosity I'm trying to find the hardness of my King Neo stone. I don't see lots of values for silicon carbide in the Hrc scale. I came across a post at Blade Forums that said SiC is around 90 Hrc. Does that sound about right to you?

[Brown_Recluse]

S90V is the knife steel to beat all knife steels imo. I have a PM2, Para 3, a Delica and a knife by another company in S90V and 3 out the 4 I usually have within reach either in my pockets or a bag of some sort. That other one kinda just sits in a drawer.

I really missed my chance with the S90V/CF Shaman tho. I still remember that day.... and being broke as a joke 🫤. It was a tough one but i survived.

but yeah, S90V is good stuff, for real, that's y it's at the top of my list

[Gtscotty]

I only have one S90v blade, a DTL Para 2, but the steel is climbing up my favorites list, great edge retention and enough corrosion resistance and toughness for most uses. I'm hoping for more S90v sprints in the near-ish future.

[Traditional.Sharpening]

Every time I read to stay away from certain steels….in this case, due to sharpening difficulty….others come along with a love of that steel

So, is it hard to sharpen, or exaggerated rumor?

Probably just people using the wrong abrasives. Diamond or CBN stones will make quick work of S90V no problem in my experience.

That depends on the size of the grit in general as ceramics or SiC will cut most all steels given a proper stone design that matches the speed of abrasive release to the grinding pressures and nature of the steel. In general, when you get to approach the size of the actual carbides matching the size of abrasive particles it starts to really matter a great deal more.

[Brock O Lee]

I am ready to pounch on a CF S90V Military 2...

[Justintoxicated]

Just how much more edge retention does S90v have over cruwear in actual use?

Tring to determine if I need a second PM2 in S90v.... Or maybe I should wait for another knife to come avaiulable in this steel...

On BladeHQ site, they are listed as pretty similar in hardness, with S90v having better edge retention, but MUCH harder to sharpen.

Granted I didn't have much of an issue shaprening my 15V mule on my KME...

[Bemo]

Your question has a long, complex, answer. Of which I'm not going to attempt. However, hardness isn't the only variable when it comes to a steel's edge retention. An given how individualized "actual use" is, it's really hard to compare. Larrin Thomas is a metallurgist who's done extensive testing comparing various steels and edge retention. Here's the link to the article that may answer your questions: https://knifesteelnerds.com/2020/05/01/ ... fe-steels/

Lot's of knowledge there.

[Justintoxicated]

Your question has a long, complex, answer. Of which I'm not going to attempt. However, hardness isn't the only variable when it comes to a steel's edge retention. An given how individualized "actual use" is, it's really hard to compare. Larrin Thomas is a metallurgist who's done extensive testing comparing various steels and edge retention. Here's the link to the article that may answer your questions: https://knifesteelnerds.com/2020/05/01/ ... fe-steels/

Lot's of knowledge there.

I think S90v is missing from the edge retnetion chart, however I guess it is supposed to be better than S110v? So edge retension should be great, but I keep hearing people say they don't like S90v because it is too chippy and too hard to sharpen. Sounds like I may be better off with something like M4, or S45vn if I want a stainless option?

[Bolster]

…The UF sharpmaker stones do nice for touch ups, but good to know the first real reprofiling needs cbn or diamond…

Unless I’m misunderstanding, Shawn’s point is that diamonds/cbn for the final/fine stone/paste is of benefit for high vanadium (and other hard) carbide steels—not just for reprofiling or initial sharpening. It sounds to me like using diamonds all the way up to very fine grit, and THEN using ceramic ultrafines to finish, actually puts me back a step (for hard carbide steels). And that is what I have been doing! So for me, Shawn is exorcising some of my stupidity. Appreciated! Didn’t realize I was undoing myself at the end. But once explained, seems very logical.

New plan is to finish with a diamond paste stropping instead.

[Spyderwebs]

Excellent point Bolster, I got that backwards.
This is probably why I notice a larger difference diamond stropping 15V and S90V vs VG10 or Cruwear. Time to pony up for some real stones now