magnacut toughness in a long fixed blade.

Test #5 sharp angles against mdf board

So this was a potential weak point one maker pointed out in my design and felt I should change or modify it so the angles weren't extreme or meeting in a point like that. I argued that because it was being made mfrom magnacut, and because the bottom side was curved so it was only one sharp angle rather than two sharp angles meeting that it would be fine, but despite that he stilled disagreed with me and thought I should change it. Thius this test to see who was right.
https://imgur.com/a/5mZgM2I

https://imgur.com/a/y5avsMr

That's 3 strikes

https://imgur.com/a/XsRX2GJ

That's 8

https://imgur.com/a/bXQ6g0i

That's 19......

https://imgur.com/a/yjruEhQ

And that's almost to many to count but I think it was 31 - 32 strikes!

MDF board is among the hardest and densest of all wood you can buy, if not the denset period. It's denser than oak, harder to cut than oak, there's almost no comparison, the stuff is heavy and hard on any tool you use on it, I know from experience of using this stuff and having personally seen some people break the tips off their pocket knives in dumb attempts to stab through it that it's some heavy duty stuff. it's basically manufactured from using epoxys and putting tons of pressure on the material to make it.

So how did this supposedly "weak" point of my blade do?
 
https://imgur.com/a/WamWddG

Absolutely no problem at all!

Conclusion:

What I have is an amazing blade that more than lived up to my expectations of it, it's extremely strong and tough. Magnacut is a great steel for longer chopper/ machete/ bolo type blades and don't let any maker suggest to you that you need AEB-L, L6 or 5160 to make these types of blades if you want them to be tough, it's not necessary, magnacut is just fine for the purpose and you get extra wear resistance if that's important to you.

Thank for following me in these tests, I hope you guys have learned something!
 
Rockwelledge75 said:
I might just take you up on that David,
Click to expand...

To be clear, you laid down the challenge, and I stated I'd take you up on it. And I am not using my "best chopper" as you suggested to Crag, but my favorite big knife, that in my opinion serves as a viable "one knife solution" for wilderness use, which is the role you claim your knife fills. Or would you now say your knife is really just a chopper?

In your testing I don't suppose you had hard chops with suboptimal edge alignment due to fatigue, accidental misstrikes into rocks, etc.
 
David Mary said:
To be clear, you laid down the challenge, and I stated I'd take you up on it. And I am not using my "best chopper" as you suggested to Crag, but my favorite big knife, that in my opinion serves as a viable "one knife solution" for wilderness use, which is the role you claim your knife fills. Or would you now say your knife is really just a chopper?

In your testing I don't suppose you had hard chops with suboptimal edge alignment due to fatigue, accidental misstrikes into rocks, etc.
Click to expand...
Yea, I mean that's fine David, there's some killer choppers out there that excel at JUST chopping, blades with .35 inches spines stuff like that, I'm not looking to get into a purely chopping challenge. but if you're down for a mixed challenge with some chopping of common trees and branches you'd find out in the wild along with slicing of things like rope and cardboard that'd be cool.

My claim is I have a good well rounded, or all purpose blade, so bring your all purpose blade to the test, I'm not looking to go up against an "axe" with a knife handle on it lol


I can't say for sure if I misalinged a few of my strikes, I think might have through, been kind of out of practice. No, I didn't hit any rocks, but if that's your only reason for choosing AEB-l over magnacut, then I just say be more careful and don't go chopping things near rocks!

by the way, I have nothing against AEB-l, people can make there long blades out of whatever they want, I chose magnacut because I knew I would be slicing with it sometimes and I wanted a more scratch resistant surface.


My only point is Magnacut and even steels like cpm cruwear and 4v shouldn't be dismissed, everyone has certain requirements and what they want their blade to achieve or do for them.
 
Last edited:
AEB-L is higher in toughness, costs significantly less in materials and processing, and the user doesn't have to avoid tasks in the field just because there are rocks that could cause chips that are impossible to fix in the field. Not to mention that a knife this size is this size particularly because its main cutting job will be chopping instead of slicing, which means that the biggest strength you've cited of MagnaCut over AEB-L (higher wear resistance) is not going to be taxed on most of the uses a big knife like this will see, whereas the advantage that AEB-L has over MagnaCut (higher toughness) will be more often. And the toughness of AEB-L will allow its geometry to be thin enough to where a steel like MagnaCut would not hold up in similar use. These are some of the reasons why, in my opinion, AEB-L is a better alloy for "all purpose" big knives, and why it is my recommendation to customers, and won't offer something this size in MagnaCut, unless I'm specifically asked for it, which has only happened twice.

Now that I am thinking of it, R Rockwelledge75 , I don't think you shared the geometry of this blade yet? What is the thickness behind the edge bevel at the chopping sweet spot, and the angle of the edge, if you don't mind sharing. Thanks!
 
David Mary said:
AEB-L is higher in toughness, costs significantly less in materials and processing, and the user doesn't have to avoid tasks in the field just because there are rocks that could cause chips that are impossible to fix in the field. Not to mention that a knife this size is this size particularly because its main cutting job will be chopping instead of slicing, which means that the biggest strength you've cited of MagnaCut over AEB-L (higher wear resistance) is not going to be taxed on most of the uses a big knife like this will see, whereas the advantage that AEB-L has over MagnaCut (higher toughness) will be more often. And the toughness of AEB-L will allow its geometry to be thin enough to where a steel like MagnaCut would not hold up in similar use. These are some of the reasons why, in my opinion, AEB-L is a better alloy for "all purpose" big knives, and why it is my recommendation to customers, and won't offer something this size in MagnaCut, unless I'm specifically asked for it, which has only happened twice...
Click to expand...

I wish you could readily get 14C28N up there. While a small step down from AEB-L in toughness, it's closer to AEB-L than to MagnaCut on toughness. It's also closer to MagnaCut than to AEB-L on corrosion resistance. It's a fantastic fine-grain Goldilocks that deserves more use in plus-sized blades.
 
Rockwelledge75 said:
Test #5 sharp angles against mdf board

MDF board is among the hardest and densest of all wood you can buy, if not the denset period. It's denser than oak, harder to cut than oak, there's almost no comparison, the stuff is heavy and hard on any tool you use on it, I know from experience of using this stuff and having personally seen some people break the tips off their pocket knives in dumb attempts to stab through it that it's some heavy duty stuff. it's basically manufactured from using epoxys and putting tons of pressure on the material to make it.
Click to expand...

MDF janka hardness is in 1000-1500 lbf, which is not hard. More basic info on Janka Hardness here: https://en.wikipedia.org/wiki/Janka_hardness_test

Since you didn't answered my ask earlier about edge geometry, so from pic of blade & edge and mdf chops (especially mdf cracks/buckles), my guessing-calc edge geometry of this blade ~ sharpened 20-22dps, 0.024-0.026" BET.
 
Richard338 Richard338 if it was mentioned, my apologies, but what is the HRC? Thanks!
 
BluntCut MetalWorks said:
MDF janka hardness is in 1000-1500 lbf, which is not hard. More basic info on Janka Hardness here: https://en.wikipedia.org/wiki/Janka_hardness_test

Since you didn't answered my ask earlier about edge geometry, so from pic of blade & edge and mdf chops (especially mdf cracks/buckles), my guessing-calc edge geometry of this blade ~ sharpened 20-22dps, 0.024-0.026" BET.
Click to expand...
Yea, I shouldn't have said hard, I just meant to convey it was super dense and has some additional properties to it that make it hard to cut. I've seen saw motors burn out on mdf where as the same exact saws will go through oak all day long.
 
Rockwelledge75 said:
62.5,
Click to expand...

Thank you.

Rockwelledge75 said:
I already said that
Click to expand...

Glass-for-you.jpg
 
David Mary said:
Thank you.



Glass-for-you.jpg
Click to expand...
So I'm just curious David, what would you suggest for an all around good blade for camping, something that could slice and chop, maybe not the absolute best at chopping but still very good?

I know your choice in steel, but I've not seen your pick in terms of blade profile and geometry for something that would fit this bill.

Can you post pics of this and also post a pic of what you'd choose if additionally you wanted it to have good stabbing power too?

just trying to get a good idea of your approach to this and just how really different it is to my own.


Thanks
 
I stated my favorite is the Barax, but there is no end to designs that I think would fill that role. It all comes down to what the user wants. And if within that desire there is room for good ergonomics, tough, simple alloy steel and thin geometry, then I am much more likely to take the job. This hidden tang Suretouch handled Khukuri in 8670 I made in 2022 would be an example of a knife suitable for camping that can slice exceptionally well, chop hard, stab with authority, move with speed, and be easy to carry and maintain in the field. It's not the definitive example of a one knife solution, just one of many possibilities.

img_6674-jpg.1827577
 
David Mary said:
I stated my favorite is the Barax, but there is no end to designs that I think would fill that role. It all comes down to what the user wants. And if within that desire there is room for good ergonomics, tough, simple alloy steel and thin geometry, then I am much more likely to take the job. This hidden tang Suretouch handled Khukuri in 8670 I made in 2022 would be an example of a knife suitable for camping that can slice exceptionally well, chop hard, stab with authority, move with speed, and be easy to carry and maintain in the field. It's not the definitive example of a one knife solution, just one of many possibilities.

img_6674-jpg.1827577
Click to expand...
That's a great looking kukri David! Yea, that Barax machete is interesting, I've never heard of them before you talked about them, I assume the extra long handle on it compared to normal machetes is for using two hands similar to a katana, I'm not sure if it would chop better than a blade that's more bolo shaped though.
 
David Mary said:
I stated my favorite is the Barax, but there is no end to designs that I think would fill that role. It all comes down to what the user wants. And if within that desire there is room for good ergonomics, tough, simple alloy steel and thin geometry, then I am much more likely to take the job. This hidden tang Suretouch handled Khukuri in 8670 I made in 2022 would be an example of a knife suitable for camping that can slice exceptionally well, chop hard, stab with authority, move with speed, and be easy to carry and maintain in the field. It's not the definitive example of a one knife solution, just one of many possibilities.

img_6674-jpg.1827577
Click to expand...
Oh boy! Now I "need" another DMC!
 
David Mary said:
I stated my favorite is the Barax, but there is no end to designs that I think would fill that role. It all comes down to what the user wants. And if within that desire there is room for good ergonomics, tough, simple alloy steel and thin geometry, then I am much more likely to take the job. This hidden tang Suretouch handled Khukuri in 8670 I made in 2022 would be an example of a knife suitable for camping that can slice exceptionally well, chop hard, stab with authority, move with speed, and be easy to carry and maintain in the field. It's not the definitive example of a one knife solution, just one of many possibilities.

img_6674-jpg.1827577
Click to expand...

David's handle inherently looks comfortable..... & I'm All about handles.
 
Rockwelledge75 said:
So I'm just curious David, what would you suggest for an all around good blade for camping, something that could slice and chop, maybe not the absolute best at chopping but still very good?

...
Click to expand...

CruforgeV 62.5rc 15dps bolo edge is quite good at chopping and slicing but a lousy B&T


This CFV bolo edge was nifty rippled (no chipped), loss about 1/16" height to fixed it for the video above


Here is Magnacut with 12dps Chops 2x4 (Oct 28 2021). This edge(including 15dps) would collapse (huge chip) if cross grain chops 1" dia seasoned blue gum branch.

When considering an edge tool for high impact/shock/lensile load, supportive flexural strength(https://en.wikipedia.org/wiki/Flexural_strength) is critical. Low tensile stress is intrinsic property of high alloy material, especially at 60+rc. I've had a few high alloy(3V, A8M, Aebl, S90V, etc..) choppers split in halves when subjected to moderate tensile stress load.
 
You must log in or register to reply here.
Back
Top