S30V and hardning?

[gull wing]

What hardness do various manufacturers harden their blades?
I have Kershaw, Spyderco, Benchmade, Sebenza, Strider knives in the steel.
Most act about the same(that is hold an edge), but it seems my Sng gets dull quicker. Disclaimer=I love my SnG and don't hold that aganist it.

Now I know edge profile has something to do with that, but an SnG is thicker than the others and should hold up?? I suddenly realized I sharpened the blade so it's down by 1/8" less in width.

 

[AMRaider]

CRK heat treats their Sebenzas to RC 58-59.

Benchmade heat treats their S30V to RC 58-60 in at least some of their knives.

Regarding edge profiles, a thicker bevel will give you increased toughness and strength at the expense of sharpness. For example a thick edge on a knife may be robust enough to chop bones. Take the same edge down really thin and it will slice much better, but will probably chip if taken to a bone. Cheers.

 

[Buzzbait]

Interesting. I prefer the Strider S30V of my SNG to the other S30V I've tried. Strider seems as though they are willing to go a bit harder on the heat treat, creating a longer lasting edge. Not as easy to sharpen, but longer lasting, and with fewer wire edge issues.

I've tried other S30V folders with the same edge thickness and sharpening angle as the SNG, and the SNG edge held up better. While other blades suffered from prematurely deformed edges, the Strider just kept going.

Overall, I'm impressed with S30V. The only S30V that I didn't like was on a Sebenza. Far too soft for my tastes.

 

[Reeek]

I still think S30V is today's best OVERALL domestic steel for cost versus performance, when heat treated well. I like VG-10 as a great OVERALL steel for non-domestic steels.

 

[JAB]

IIRC, Striders are hardened to RC 59-60.

 

[gull wing]

Intresting Buzzbait, my SnG is MUCH easier to sharpen than my other S30V knives. As a matter of fact when reprofileing(Edge Pro), I was shocked at how fast I got the bevel on the SnG. With all other S30V knives, it takes much longer to reach the bevel.

 

[Buzzbait]

Intresting Buzzbait, my SnG is MUCH easier to sharpen than my other S30V knives. As a matter of fact when reprofileing(Edge Pro), I was shocked at how fast I got the bevel on the SnG. With all other S30V knives, it takes much longer to reach the bevel.

Hmmmmm.. I guess that's the variation in hardness.

 

[gull wing]

Must be!

 

[AMRaider]

Intresting Buzzbait, my SnG is MUCH easier to sharpen than my other S30V knives. As a matter of fact when reprofileing(Edge Pro), I was shocked at how fast I got the bevel on the SnG. With all other S30V knives, it takes much longer to reach the bevel.

Edge geometry is probably a factor here. Unless you are dealing with same grind and bevel, it will be difficult to accurately compare sharpening steels on different knives.

 

[Jason B.]

Can't comment on the strider or sebbie but of the other 3 kershaw S30V performs the best and seems to be the hardest.

 

[Buzzbait]

Edge geometry is probably a factor here. Unless you are dealing with same grind and bevel, it will be difficult to accurately compare sharpening steels on different knives.

The unusual thing is that the thicker blade grind should be harder to sharpen. The edge thickness on an SNG is thicker than many folders on the market. Mine measures out to .027". So theoretically, the SNG should be harder to sharpen. The fact that Gull wing finds the SNG to be easier to sharpen suggests that he either has some VERY thick bladed or hard S30V knives, or that his S30V is definitely on the soft end of the heat treat range.

 

[lambertiana]

A month or two ago Chuck Buck posted in the Buck forum that they do their S30V to 60-60.5.

Spyderco says theirs is 58-59.

 

[Twindog]

There is a reason that the hardness is listed in a range, rather than a specific number. Then there are other factors, such as how it was sharpened and whether the edge grind is even, etc.

Steels come in a range, as well, such as how much chromium is in them. You think D2 is not stainless, because stainless is defined as 13 percent chromium? Well, some D2 is stainless and some is not. You don't know EXACTLY what your getting when you buy a knife.

Back in my hot-rod days, we used to balance and blueprint engines. The idea was to take out as much of this variation as possible. Knives are not that way. People can have a good experience with a knife/steel/brand or a bad experience with a knife/steel/brand and the difference is in all the little details that vary by quite a range.

 

[AMRaider]

The unusual thing is that the thicker blade grind should be harder to sharpen. The edge thickness on an SNG is thicker than many folders on the market. Mine measures out to .027". So theoretically, the SNG should be harder to sharpen. The fact that Gull wing finds the SNG to be easier to sharpen suggests that he either has some VERY thick bladed or hard S30V knives, or that his S30V is definitely on the soft end of the heat treat range.

Well, I did some calcs* and contrary to what I thought (I thought that you had to remove more material to sharpen a thin edge versus a thick edge) the amount of material removed is the same (with all else being equal: same thickness stock, and same amount of "damage" to the blade).

The only thing I can think of to account for the difference is that with a thin edge, a greater portion of the blade will be in contact with the stone than with a thick edge. So, more pressure will be needed to remove the same "thickness" of the material. However, with a thinner edge, a lesser "thickness" will need to be removed. So.. I'm afraid I don't have an answer, except that I'll have to agree with Buzzbait, and say that the temper must be different.

*I apologize for not putting up my calcs, so anyone reading this will have to take it with that grain of salt so to speak. I'm unable to post pictures and to try to explain it with my poor writing skills would be time prohibitive on my part.