Edge Testing - Blades That Cut Metal

[Bigfattyt]

Ya, I just can't think of any situation or predicament, even in a world collapse, zombie apocalypse........where I would ever need to take a knife and vice it down, and hit it sideways with a sledge hammer!!

Some of the knives just kept going, and going, and going!!!!

I already owned Busse at that point, and was a fan of Keffler's swords and knives, so it did not really affect my purchasing habits. But it was fun!!!!

 

[Nathan the Machinist]

I have been super happy with M4 on my folders over the years but lately it seems like 4V is becoming more popular for similar knives. Are there things that 4V will do that M4 will not? Or is there a little bit of newer is better going on?

Sorry I didn't mean to derail. I thought this was semi related to the subject and also you have probably tested both.

Optimized 4V may have a little bit better balance of properties. It is so much tougher than M4 that you can run it really hard without risk of chipping. 4V responds well to the low temp tweaks that are optimized for cutlery that avoids the use of the secondary hardening hump and achieves better edge stability. I don't know if M4 can be run that way. 4V makes a reasonably tough and durable knife at HRC64. M4 performs well there, but can't be run as thin without risk of failure. I think they're both great steels but I think M4 may be a bit off to one extreme and would benefit from the substantially improved durability you get with 4V.

 

[Storm W]

Optimized 4V may have a little bit better balance of properties. It is so much tougher than M4 that you can run it really hard without risk of chipping. 4V responds well to the low temp tweaks that are optimized for cutlery that avoids the use of the secondary hardening hump and achieves better edge stability. I don't know if M4 can be run that way. 4V makes a reasonably tough and durable knife at HRC64. M4 performs well there, but can't be run as thin without risk of failure. I think they're both great steels but I think M4 may be a bit off to one extreme and would benefit from the substantially improved durability you get with 4V.

Thanks for taking the time to respond. I have a fair stock of M4 saved up and I hope to play with it. If I can get my butt to the store and get some LN. Do you have any advice about where to start with it? I'm doing some chef knives and maybe a couple of EDC's just to play with. My only experience has been Some non PM M2. I ran it hard. I don't have a tester but Warren got 66Rc with the same recipe. I really liked it. It felt super toothy and reminded me if your description of your D2 and why to use non PM. I'm willing to donate some in the name of science to Larrins test if there is anything interesting to try M2 or CPM M4. I know you have done some cool stuff and thought maybe there is something interesting I could try for the test. I'm a big fan if your work and someday I hope to own a couple of pieces.

 

[Willie71]

Optimized 4V may have a little bit better balance of properties. It is so much tougher than M4 that you can run it really hard without risk of chipping. 4V responds well to the low temp tweaks that are optimized for cutlery that avoids the use of the secondary hardening hump and achieves better edge stability. I don't know if M4 can be run that way. 4V makes a reasonably tough and durable knife at HRC64. M4 performs well there, but can't be run as thin without risk of failure. I think they're both great steels but I think M4 may be a bit off to one extreme and would benefit from the substantially improved durability you get with 4V.

I agree with everything you say here. I’ve made over 100 knives in z-wear now, and asked people to abuse them. One fellow used his as a throwing knife at Rc62 and didn’t break it. My friend Bruce had his skinner out this weekend. Hadn’t sharpened it since I made it 2.5 years ago. Still shaved, barely lol! I haven’t made one less than Rc62 yet. V4E is very similar. I have only made three V4e knives so far. I think at Rc62-64, they are basically interchangeable. Below Rc62, z-wear is probably a bit tougher. At Rc65, V4e is a hair tougher. At Rc63-65, both are tougher than O1 or 1095 at Rc58-60. What more do we need? If you want super tough, z-tuff, or 8670 at Rc61 will hold up to anything you throw at it, outside of throwing knives.
I’m using less than 0.005” before sharpening with z-wear. Not just kitchen knives. EDCs. They hold up.