High-hardness choppers

[HSC ///]

i just got invited to try my hand for a local knife club cutting competition.
As someone who makes 64RC edges, I'm very interested in this

thank you

 

[spyken]

how much does Luong charge for re-heat treating? is this a viable option for other blades with possibly poorer heat treat? high hardness vs toughness - the results just seem to defy traditional logic? how about edge-holding?

all my 3V blades have rolled and a reheat treat option is attractive to me. but when you re-heat treat, what happens to the original handles?

 

[Chris "Anagarika"]

Twindog,

Thank you for the test and sharing it. Interesting comparison.
:thumbup:

 

[mmmotorcycle]

Very neat tests, Twindog. Some sites have the BRKT Senegal on sale for around $200-ish. Would you say it would be a good intro to a heavy (10+ inch tool) chopper? I don't have much use for one but relatives of mine in Florida love American made stuff.

As an extra note threads like this are why I picked up the Knife Research Enki, using Vanadis 4E. I have noted similar awesome performance for me, a casual hiker/bushcrafter and outdoors person, seeing much less maintenance or worry during normal use.

 

[Twindog]

Very neat tests, Twindog. Some sites have the BRKT Senegal on sale for around $200-ish. Would you say it would be a good intro to a heavy (10+ inch tool) chopper? I don't have much use for one but relatives of mine in Florida love American made stuff.

As an extra note threads like this are why I picked up the Knife Research Enki, using Vanadis 4E. I have noted similar awesome performance for me, a casual hiker/bushcrafter and outdoors person, seeing much less maintenance or worry during normal use.

It really depends on what you have to chop. I know nothing about the conditions in Florida. The Senegal is a big, heavy chopper with a 14 inch blade. I love it, but it's heavy -- 2 pounds 3 ounces. I wouldn't want to use it for long. The fit and finish on mine are beautiful. My only concern is the heat treat. A2 steel is a tough steel, but mine failed the wire-chopping test that all the other choppers, with the exception of the machete, passed. Basically, the edge folded around the wire. But I didn't experience any blade damage on cutting heavy, woody brush. I'd be happier if Bark River put this out in 3V. The sheath is beautiful -- high-quality leather. The only defect is that I can pull the knife out of the sheath without unsnapping the security flap.

Bark River also has a smaller version, the Dakkar, with a 9.4 inch blade that comes in at 1 pound 5 oz. It, too, uses A2 steel, but at a higher hardness -- 59-60 Rc, compared to 58 Rc for the Senegal.

 

[mmmotorcycle]

Thanks again for your commentary on these tools. I will have to ask my uncle about his glove size since he may need something with a larger handle than Bark River offers. I am sure I will figure something out.

 

[BluntCut MetalWorks]

I got W2 chopper back from Twindog. Packaging & chopper condition were too perfect (thanks Twindog!) - as if it never left my place. Promptly, I took a few closeup pics of the edge after Twindog's baling wire chopped. Clearly there were multiple impacts with the wire. Edge took less damages than I expected.

Ruler tick every 1 mm

 

[Teppojutsu]

Excellent testing twindog!

Very awsome of you to send your blades out for testing bluntcut
Definitely subscribed :thumbup:

Edit if you ever need another tester let.me know!
I got a whole bunch of alaskan birch and spruce dried and seasoned
I might be able to dig up some moose antlers to chop on as well

 

[Twindog]

In another thread, someone was asking about Elmax, which is generally considered one of the toughest of the stainless steels. I had a spare custom that I bought on the forums that was heat treated to 60 Rc. I though I'd add the results to this thread. One thing that really stands out is that the bailing wire test is pretty darn hard, but the best steels with the best heat treats can handle it.

Here is a custom knife in Elmas at 60 Rc:
]

Here’s a hand-forged blade in 1095 at about 60 Rc:

Here’s a 3V blade at 60.5 Rc:

Here’s an M4 blade at 64 Rc by Gillson, which is almost untouched:

Here’s a Zero Tolerance in Vanadis 4E (unknown hardness) that is barely damaged:

Here are the players:

 

[bodog]

If I remember right ZT said their target on that 0180 was 62 RC.

That elmax blade was from a European dude here on the forums, right? I haven't seen him offer anything for awhile.

 

[Twindog]

You're right, Bodog. I bought all of those knives from knife makers on the forums, except for the ZT. Huge difference in performance. Funny that the production blade did the best, although the Gillson in M4 is an awesome blade. The 3V is good, too.

The 1095 blade didn't do well in this test of edge stability, but it had done really well in an earlier test I did on whole-blade toughness.

Knives have a variety of essential attributes: design, geometry, balance, edge stability, ergonomics, overall toughness, wear resistance. People see one test of one attribute and think they've found a great knife. But while a knife can do exceptionally well in one area, it can fail in another. Knives are complex.

 

[GREENJACKET]

Excellent input Twindog.
As we all know edge integrity is one thing, and blade integrity another. Get one to work and the other all to often lets it all down. Trying to get both to work is the tricky bit. I have knives whose edges take damage all too easily but the blade should never brake. Others where the edge seems to last and last but I wouldn't be in a hurry to use the blade as a crow bar or put harmonics through it hammering on it. Others are a compromise. I lean towards a lighter weight blade and find far too many overbuilt; though fashions change and things are getting finer.

On the whole there are good blades being made. Always room for advancement. Its these tests and people commentating on their experiences that all go to help build the bigger picture. Cuts through a whole lot of that hype. Drawer queens don't add anything, the practical does.

So a big thank you, as my next purchase might just be better for all this. I've got good knives from 20-30 years ago, but in the next 10-20 years we might have even better ones. In the mean time I'll keep my sharpening kit at the ready and try not to chop too much bail wire.. or rock, or nail or girder post...

 

[chiral.grolim]

Wait, edge-geometry was the same for all of those? E.g. all were 20-dps? I just want to be sure, since slight variations in edge-geometry here (15 instead of 20) can make a HUGE difference in strength:

 

[Twindog]

Good point, Chiral. I was just seeing how well my blades stood up, as they were. I started out with the choppers at factory-set edges. I was measuring both chopping performance and edge stability, so I left them as the designers intended, because changing one factor would change the other. I did give edge acuity -- or estimates -- for those.

There is a clear relationship between edge acuity and edge stability. Acuity usually helps with wear resistance, but hurts with stability.

Here's the edge geometry of the smaller fixed blades:

M4 -- 23/16 (degrees per side) also this edge was convexed
3V -- 19/18
Elmax -- 15/15
1095 -- 15/15
Vanadis 4E -- 20/20
S30V -- 28/28

 

[chiral.grolim]

Good point, Chiral. I was just seeing how well my blades stood up, as they were. I started out with the choppers at factory-set edges. I was measuring both chopping performance and edge stability, so I left them as the designers intended, because changing one factor would change the other. I did give edge acuity -- or estimates -- for those.

There is a clear relationship between edge acuity and edge stability. Acuity usually helps with wear resistance, but hurts with stability.

Here's the edge geometry of the smaller fixed blades:

M4 -- 23/16 (degrees per side)
3V -- 19/18
Elmax -- 15/15
Vanadis 4E -- 20/20
S30V -- 28/28

Is the S30V supposed to be the 1095 knife?

The Vanadis 4E held it's geometry the best and is also the stoutest at 20/20 (40 inc)
The M4 is 39 inclusive (effectively 19.5 dps?) and 2nd-best
The 3V NTM field knife is is next and 37 inc at 19/18
The Elmax and 1095 fared worst, with the Elmax being 15/15 which is >2X weaker than the 20/20.

 

[Twindog]

Is the S30V supposed to be the 1095 knife?

No the S30V was from the earlier test. The 1095 was also 15/15. I'll edit that test. So, as you note, edge acuity is a strong driving factor.

 

[Twindog]

This was interesting. I reprofiled the Elmax and 1095 edges to 40 degrees inclusive. Both had been tested at 30 degrees inclusive. There was very little edge damage after wire chopping with the new edge profiles. Geometry matters. When testing for edge stability alone, the edges on the small fixed blades should have been given the same profile.

I tend to sharpen all my EDC blades to 30 degrees inclusive because of the better cutting ability. But I think I need to switch my larger blades, where chopping might be required, to 40 degrees inclusive.

This is the 20/20 Elmax edge after chopping

This is the 20/20 1095 edge after chopping

 

[chiral.grolim]

Talk about a clean experimental follow-up, well done :thumbup:

NOW the tougher question - what would happen if you thinned the previously thicker edges down to 15/15 and tested them again? Would the 3V and M4 and V4 hold up better than the 1095 and Elmax at those levels...?

 

[Twindog]

Talk about a clean experimental follow-up, well done :thumbup:

NOW the tougher question - what would happen if you thinned the previously thicker edges down to 15/15 and tested them again? Would the 3V and M4 and V4 hold up better than the 1095 and Elmax at those levels...?

I tried it on the Vanadis 4E blade, reprofiling the edge from 20/20 to 15/15. There was a little more damage, but not much. This is good steel with a good heat treat.

Vanadis 4E reprofiled to 15/15

 

[noob93]

awesome this was great information for me and i appreciate the follow up. I thought the angle looked quite acute on that elmax blade so ya i guess my question would be the same as chiral.grolim.