S30V chipping

singularity35

singularity35

Joined
Mar 1, 2010
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I used my all black military to chop some palm fronds. These palm fronds were green so not very tough at all. I just received my jeweler's loupe from ebay and immediately used it to look at all my edges. I found some tiny chips on the area that cut the fronds. Nothing major though. I just sharpened them away. I hope that that was just the metal of the factory edge that they say has been ruined by the heat of the belt sander.
 
singularity35 said:
I used my all black military to chop some palm fronds. These palm fronds were green so not very tough at all. I just received my jeweler's loupe from ebay and immediately used it to look at all my edges. I found some tiny chips on the area that cut the fronds. Nothing major though. I just sharpened them away. I hope that that was just the metal of the factory edge that they say has been ruined by the heat of the belt sander.
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If you look at any edge under high enough magnification you'll notice things you wish you hadn't. :)

That being said, depending on what you're seeing it might not be chips but instead the softer steel wearing away exposing the toothy carbide structure underneath. That's what makes the steel so wear resistant is the massive amount of carbides present.
 
It seems crazy to be worried about chipping that is only visible under magnification.
 
AF said:
It seems crazy to be worried about chipping that is only visible under magnification.
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Yeah, that's what I thought. Still, the first time you look at a knife that closely it will probably make you more self-conscious about how you use it.
 
D1omedes said:
Yeah, that's what I thought. Still, the first time you look at a knife that closely it will probably make you more self-conscious about how you use it.
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So true, I saw a folder being used to chop in a video and I'd thought I'd try it. As anal as I am, now it seems to me to be abuse.
 
Get yourself an Ontario Rat 1 folder and use it for the chopping chores. They're tanks, I've seen them baton wood on YTube and still lock up tighter than a drum. :)
 
cziv said:
Get yourself an Ontario Rat 1 folder and use it for the chopping chores. They're tanks, I've seen them baton wood on YTube and still lock up tighter than a drum. :)
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Not in my experience. Chopping with a RAT-1 will break the stud that the blade locks against in short order.
 
singularity35 said:
The chips sharpened away easily enough though.
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I had read on a thread here a while back that a problem with some factory edges are that the steel stock is sometimes brittle at the cutting edge (end result of some heat treats). The knives are sharpened but the stock can still be brittle as the sharpening process does not remove enough.

I'm sure if you sharpen the knife and create accurate bevels, you would see a lot less chipping the 2nd time around. For what it is worth, I would much rather have some microchipping than edge rolling.:D
 
I have encountered one concern regarding S30v microchipping when repeatedly cutting comparative soft cardboard or other fibrous material with a blade having a relatively thin edge grind angle. (30 degrees or less) The fibrous structure of the material being cut can grab onto the edge of a micro chip or tiny crack. Absent the full supporting structure of surrounding steel, the localized stress can rip out a small section of the cutting edge. This creates a larger chip which presents a greater opportunity for more fibers to grab the edge resulting in larger chipping. A vicious circle of cause and effect. The solution, I've found, is a careful resharpening below the depth of the chips and a polishing of the edge to prevent cutting material from getting a grip. This has largely eliminated the problem. So far, I have only encountered this with blades made from S30v and D2 steel. Or, I could just be old and senile. OldDude1
 
OldDude1 said:
I have encountered one concern regarding S30v microchipping when repeatedly cutting comparative soft cardboard or other fibrous material with a blade having a relatively thin edge grind angle. (30 degrees or less) The fibrous structure of the material being cut can grab onto the edge of a micro chip or tiny crack. Absent the full supporting structure of surrounding steel, the localized stress can rip out a small section of the cutting edge. This creates a larger chip which presents a greater opportunity for more fibers to grab the edge resulting in larger chipping. A vicious circle of cause and effect. The solution, I've found, is a careful resharpening below the depth of the chips and a polishing of the edge to prevent cutting material from getting a grip. This has largely eliminated the problem. So far, I have only encountered this with blades made from S30v and D2 steel. Or, I could just be old and senile. OldDude1
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What do I know but I think you're right and that this may be a quality of this steel when sharpened at 30 degrees. Maybe 40 degrees inclusive will largely deal with this. I would sacrifice some performance just to lessen microchipping.
 
OldDude1 said:
I have encountered one concern regarding S30v microchipping when repeatedly cutting comparative soft cardboard or other fibrous material with a blade having a relatively thin edge grind angle. (30 degrees or less) The fibrous structure of the material being cut can grab onto the edge of a micro chip or tiny crack. Absent the full supporting structure of surrounding steel, the localized stress can rip out a small section of the cutting edge. This creates a larger chip which presents a greater opportunity for more fibers to grab the edge resulting in larger chipping. A vicious circle of cause and effect. The solution, I've found, is a careful resharpening below the depth of the chips and a polishing of the edge to prevent cutting material from getting a grip. This has largely eliminated the problem. So far, I have only encountered this with blades made from S30v and D2 steel. Or, I could just be old and senile. OldDude1
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Cardboard is also incredibly abrasive, chunks of random crap everywhere. It's not simply thick paper.
 
The solution, I've found, is a careful resharpening below the depth of the chips and a polishing of the edge to prevent cutting material from getting a grip. This has largely eliminated the problem.
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I think you're spot on OldDude1, that is exactly my observation as well. Of course I've stopped using the very acute angles lately and use about a 40* bevel with a good strop to polish the edge.

I don't use much in the way of magnification, just a cheap plastic magnifying glass from Wally World. :)
 
You are of course quite right a 40 degree angle or microbevel also addresses the problem most effectively. I reprofiled to 30 degrees on several S30v blades in order to take advantage of the allegedly superior attributes of the ''super" steel. In use, the blade's resistance to wear is highly noticeable but it's propensity for micro chipping requires about the same amount of attention that a a lower carbide steel calls for to due to wear, rolling or dulling. I have found that this somewhat defeats the overall superiority of it's edge holding ability. So far, I have not noticed similar problems with knives of S90v or ZDP steel. OldDude1
 
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