Knives go dull for no reason?

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Oct 19, 2004
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I have at least one knife that I hardly ever use (S30V), and I swear it's not as sharp today as the day I bought it. It is my CUDA Dominator. Am I going crazy, or is my knife going dull by just sitting there? When I got it, I could shave hair off my arm very easily, now I have to put considerably more pressue on my arm and take more strokes to shave smaller amounts of hairs. Also, what is your opinion on the Edgepro system? Worth the money? I know some will say to get the spyderco sharpmaker, but I'm not good at delicate operations like sharpening, so I need a more foolproof system, that holds the blade and stone at a particular angel, to make up for my unsteady hand that will result in inconsistent angles with every strope.

Thanks for your input

Charlie
 
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a very fine edge will corrode no matter what the steel. It means knives will go dull without any use. carbon is worse
 
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I don't know if that makes me feel better or worse. So, the out of box sharpness of your knife could depend slightly on how long it's been on the shelf. Very interesting. I guess I have no choice but to invest in an Edgepro now. I was hoping that my S30V blades as well as my D2 stuff would stay sharp forever as long as i don't ever abuse them, I guess not. Wow, thanks for the input.
 
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Micro-corrosion seems the best explanation for this. It definitely happens more to non-stainless steels, but it happens to stainless as well.


I've also heard theories that if there's a wire edge, that edge can "relax".
 
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I just don't buy that a knife will get dull just by sitting there unless it is visibly rusting.

I have a couple of Pacific Cutlery Laredo knives. PCC went out of business in what, 1988? That makes these knives at least 16 years old at least. Every one of them will easily still shave hair. The steel used is 440C.
 

glockman99

RIP Dann, you were a good guy.
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Charlie,

Maybe your wife/girlfriend is using your Dominator to shave her legs with, without telling you?.:D.:D.
 
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I've observed the effects of micro-corrosion first hand: My Buck 119 (1989) dulls without use, and requires sharpening whether it is used or not.

I've got an old Ka-Bar folder that always gets a dull spot because of the blade touching something when the blade is closed. Very annoying!

At the other end of the scale is my Grand Father's pocket knife (made in Sheffield in the 1930s) that sits in the safe year in and year out with the same razor sharp edge.

David
 
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ChuckBuck said:
I have at least one knife that I hardly ever use (S30V), and I swear it's not as sharp today as the day I bought it. It is my CUDA Dominator. Am I going crazy, or is my knife going dull by just sitting there? When I got it, I could shave hair off my arm very easily, now I have to put considerably more pressue on my arm and take more strokes to shave smaller amounts of hairs. Also, what is your opinion on the Edgepro system? Worth the money? I know some will say to get the spyderco sharpmaker, but I'm not good at delicate operations like sharpening, so I need a more foolproof system, that holds the blade and stone at a particular angel, to make up for my unsteady hand that will result in inconsistent angles with every strope.

Thanks for your input

Charlie


I really don't think that sharpening with a Sharpmaker is a "delicate operation". I am a little careful on the flats but other than that, I jus giv um. All you have to do is hold the blade verticle and stroke downwards.
 
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Sharpening with a Sharpmaker is not a delicate operation. For one thing, the ceramic rods leave a smooth finish and do not cut too fast. For another you don't really have to hold that precise an angle to get a razor edge.

I don't think it is likely to be micro corossion with a stainless alloy. I think that the factory left you with a wire edge. Basically there was some flimsy and raspy material at the edge that was initially aligned to give give a razor edge. This is like a straight razor edge. The whispy edge material is a little like microscopic hairs. Initially they are combed straight. With time they come loose from each other and get ratty and uneven. If this is actually the source of the problem you can test it. Just strop the blade lightly on a belt and if it gets back to your original sharpness with minimal effort you just have a relaxing wire edge. To get rid of it you need to do some edge-forwards honing with something like a Sharpmaker. You might permanently solve your problem by doing that.
 
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You say that you shaved hair easily the first time. Perhaps the micro-corrosion process was accelerated by contact with your skin while shaving.

Just a thought. :D
 
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Yes I suppose it's possible. Some people such as myself have acidic sweat, (at least that's what my mom says). When I wear black, after a while it looks somewhat bleached, sort of a red/black.
 
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ChuckBuck said:
I was hoping that my S30V blades as well as my D2 stuff would stay sharp forever as long as i don't ever abuse them.

they don't make knives that do this. abuse has nothing to do with it. a knife with an amazing steel will not stay sharp, even with just gentle regular use.

abe m.
 
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underaged! said:
Yes I suppose it's possible. Some people such as myself have acidic sweat, (at least that's what my mom says). When I wear black, after a while it looks somewhat bleached, sort of a red/black.

depends on the dye base. some will turn red, others green, and a few gray. happens to all of them. i wear mostly black clothes so i'm used to this sucky phenomenon.

abe m.
 
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Would a Tuff cloth prevent micro-corrosion? I'm with Jeff. I shave with straight razors and people say the wire edge can relax. So it's possible the knife has a wire edge that has changed since the knife was purchased. Could even a temperature change result in the edge curling a different way? How about humidity? :) Try stropping it on something, even maybe your jeans, and see if that helps. I think a few passes on the white sharp maker rods would do the trick though.
 
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A wire edge reforming would seem a very logical reason. Could it be affected by magnatision?

My old sheffield pocket knife is the worst for going dull without use.
 
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misque said:
You say that you shaved hair easily the first time. Perhaps the micro-corrosion process was accelerated by contact with your skin while shaving.

Just a thought. :D

Yeah, I've honestly thought of that myself, that maybe the edge is so fine that something as simple as rubbing very lightly on my skin was enough to take that hair popping scary sharpness, down to just razor sharp. Don't get me wrong the knife is still VERY VERY sharp, but it was definetly a little more wicked when I first got it.
 
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allyourblood said:
they don't make knives that do this. abuse has nothing to do with it. a knife with an amazing steel will not stay sharp, even with just gentle regular use.

abe m.

Thank you, that is pretty much what the original thread/question was asking.
 
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djolney said:
I've observed the effects of micro-corrosion first hand: My Buck 119 (1989) dulls without use, and requires sharpening whether it is used or not.

I've got an old Ka-Bar folder that always gets a dull spot because of the blade touching something when the blade is closed. Very annoying!

At the other end of the scale is my Grand Father's pocket knife (made in Sheffield in the 1930s) that sits in the safe year in and year out with the same razor sharp edge.

David

I've had my Al Mar Operator in S30V for longer than the Dominator, and it seems just as sharp as the day I got it, but then again it didn't come as sharp out of the box as the Dominator, so it doesn't have as much to lose as the Dominator. All this is very interesting, I guess part of it will have to be live and learn, I suppose. Thanks for the input. I thought I was losing it for a minute, or I got a chep knock off of a CUDA or something... but from reading these posts I guess it's not too uncommon and there is a scientific explanation.
 
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Let me clarify. You are not living in the tropics. Properly sharpened your stainess alloy knife should stay sharp for months or years without discernable dulling. You should not accept the situation. I think you can fix the problem with a little honing to get yourself a solid edge. I think this is a minor manufacturing process defect. At worst a little light stropping on leather every couple of months should keep it better than new.
 
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It also may be a case of a little overzealousness on the final edge buffing too. That may have slightly compromised the temper at the very apex of the edge right where the rubber meets the road. :)


Then again, Jeff Clark has quite possibly hit that rascally little mole right on the head with his wire edge hammer. It really is the most plausible explanation given your knife's symptoms. Sorry Jeff, I'd have agreed earlier if I'd just read your posts rather than skimming over yours and all the other posts. :footinmou
 
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