Broken full flat ground during batoning

eveled said:
Now to be fair some knives are very froe like and probably are fine to baton with. But they are not what I want to use for knife tasks.
Click to expand...
Yes! That was my point - you just got there a whole lot quicker. 👍
 
High chromium steels dont like to bend, high carbide volume and often lager grain size can lead to broken blades, try something like AEBL, 12c27,for stainless over 12% chrome,or keep it clean and forget about surface staining and go for 3v,vandius 4, or A8
 
The True North said:
Okay now kiss

Grab a Becker or ESEE and just absolutely wail on it. You'll be impressed and you won't be able to go back.
Click to expand...
Agreed! I have an ESEE 6 that I’ve used to split a lot of oak firewood before I got my Kindling Cracker, and that ESEE would flex to a disturbing degree when batoning through a knot, but it would spring back to original shape as soon as it pushed on down through.
 
TC said:
In the context of a knife, a finger choil of appr. 1" with properly chamfered edges etc. is not much of a stress riser in practice; though perhaps mathematically in theory. A narrow V-groove, repeated tenfold - aka jimping - is. And that is what I stated.
Click to expand...
What I saw that you stated, way back at the top of page 1 of this thread, was this:

"the jimping is broader but has finely machined troughs. No stress risers there!"

Not true.

While it might seem like arguing over distinctions without a difference, I guess my larger point was that if you're gonna pull out and swing around your big ... brain ... by using terms like "stress riser," you should probably use them accurately. And to refer to any discontinuity -- whether it's a radiused, chamfered jimping groove in a knife, a ripple in a weld bead, or even a scratch on a pane of glass -- as "no stress riser there!" demonstrates a fundamental lack of understanding of the concept.

Thanks for the metallurgy book suggestions, but I suspect I already have them. ;)
 
Last edited:
Cementite said:
What I saw that you stated, way back at the top of page 1 of this thread, was this:

"the jimping is broader but has finely machined troughs. No stress risers there!"

Not true.

While it might seem like arguing over distinctions without a difference, I guess my larger point was that if you're gonna pull out and swing around your big ... brain ... by using terms like "stress riser," you should probably use them accurately. And to refer to any discontinuity -- whether it's a radiused, chamfered jimping groove in a knife, a ripple in a weld bead, or even a scratch on a pane of glass -- as "no stress riser there!" demonstrates a fundamental lack of understanding of the concept.

Thanks for the metallurgy book suggestions, but I suspect I already have them. ;)
Click to expand...
All smarmy attitudes and sarcastic winking aside...






Technically any cut out, groove, or indentation on the blade will be a stress riser. But TC says "in practice"and I tend to think that in practice his statement is correct.

With the proper steel/heat treatment, and with well-designed jimping (larger more rounded, chamfered grooves vs sharp cut-outs as discussed) I think the risk of breakage at the jimping vs. somewhere else on the blade specifically due to there being stress risers is essentially equal. In practice.
 
Last edited:
The True North said:
All smarmy attitudes and sarcastic winking aside...






Technically any cut out, groove, or indentation on the blade will be a stress riser. But TC says "in practice"and I tend to think that in practice his statement is correct.

With the proper steel/heat treatment, and with well-designed jimping (larger more rounded, chamfered grooves vs sharp cut-outs as discussed) I think the risk of breakage at the jimping vs. somewhere else on the blade specifically due to there being stress risers is essentially equal. In practice.
Click to expand...

That's exactly what I meant.

In general I see today that many people - not specifically anyone in this discussion! - do not have a sense of proportion. An example: Whether one acknowledges or not that carbon emissions by cars are harmful and must be limited, publishing CO2 emissions for cars down to single gram figures (i.e. 122 g/km) is highly questionable when there are appr. 1.250,000,000,000,000,000,000 g of CO2 in the air. People are to believe that 122 or 124 is a significant difference?

Let's stick to arguments of *significance*.
 
I don't know why some people have a hard time understanding, properly machined jimping with a radius in the trough makes failures a statistically inconsequential decimal place. Yes removing material left some form of stress risers. I understand. We understand.

The point is improperly cut notches in metal results in failures, a radius that reduces that stress riser all but erases that failure in knives. If a radius was barely any advantage over a sharp angle, ok, I understand the nit picking. But... it isn't. Adding a proper radius is night and day, drastically, clearly superior as it reduces the stress point very significantly. Crying out loud.
 
All this talk has me curious on a crowned spine vs a square edge spine would be stronger. Would the more narrow contact area on a crowned spine increase the shock on the impacted area vs the square edge more evenly distributing the impact?
 
Maximumbob54 said:
All this talk has me curious on a crowned spine vs a square edge spine would be stronger. Would the more narrow contact area on a crowned spine increase the shock on the impacted area vs the square edge more evenly distributing the impact?
Click to expand...
Yes
 
shinyedges said:
I don't know why some people have a hard time understanding, properly machined jimping with a radius in the trough makes failures a statistically inconsequential decimal place. Yes removing material left some form of stress risers. I understand. We understand.

The point is improperly cut notches in metal results in failures, a radius that reduces that stress riser all but erases that failure in knives. If a radius was barely any advantage over a sharp angle, ok, I understand the nit picking. But... it isn't. Adding a proper radius is night and day, drastically, clearly superior as it reduces the stress point very significantly. Crying out loud.
Click to expand...
thread just needs more math.......
 
shinyedges said:
Math is great, while people are quibbling over numbers radiuses are being machined into parts as we speak in the real world, for very real reasons lol
Click to expand...
I appreciate that non-jimped knives are Better and somebody has the numbers to prove it..... Hahhaha! :P
 
Spyderco911 said:
I guess I took the Odenwolf in full flat (D2 steel) a little to far. Got into a big knot in some hardwood and was really wailing on it and then snap. I have the scandi grind version of the same knife that I'm sure could have taken the abuse. I have been using this guy for a while and have batoned through many pieces of wood but now I see the limitations of the full flat grind. I have definitely put mora's, even of slightly thinner stock, through more, but again those were all scandi ground, and not D2, ha. Overall, based on everthing else I have done with this knife, I would not hesitate to buy it again. It holds a great edge, did not have chipping or rolling issues with light chopping and carving into hard wood. I would just avoid batoning through dense knots in hard work, ha.

I plan on replacing with an Eafengrow EF131. Seems to me that a broken knife is worthy of a new knife purchase:cool:!
Click to expand...
You should post a pic of the offending branch, so that we know what it was that exceeded it's limits.
 
Cementite said:
What I saw that you stated, way back at the top of page 1 of this thread, was this:

"the jimping is broader but has finely machined troughs. No stress risers there!"

Not true.
Click to expand...

Yes.

But look at it this way, in knife terms: When Crocodile Dundee said "That's not a knife, THIS is a knife" - he was scientifically incorrect.

But he made a point we here can all relate to.
 
You must log in or register to reply here.
Back
Top