High vanadium knives don't need diamond stones...

[000Robert]

It is probably the stated 425M. Your approach towards sharpening them just needs alteration. Even their notoriously hard 440C will be easily cut by synthetic stones in good condition.

If you don't mind marring the blade surface, try using the chisel-like end corner of the file like a scribe to scratch the blade. Just because the file isn't biting isn't always a problem of hardness. Most people complain of the 425M blades not holding an edge well. It's not magic steel, and isn't even considered "good" by current standards. Stainless is just hard on files, especially martensitic hardened stainless. And that particular stone set sounds like there's something funky going on with it that would need refurbishing to work well.

I bought these Japanese files like in the photo. The blades do seem to hold an edge longer than usual. I also remember breaking the tip on the clip point blade and the sheepsfoot long ago and was surprised that they broke off.

 

[Obsessed with Edges]

My files are brand new and they work great on every other knife that I have. Maybe the steel is not 425M? Buck may have made a mistake and made my blades from a different steel, I'm not sure. But my 301 is the reason that I bought my DMT decades ago. I guess I need to have the steel tested.

I'm also pretty sure you've got 425M at this point. The 'X' date code stamp on the blade indicates 1990 as year of manufacture. That's too far removed from the transition periods away from either 440A (Camillus, until 1985 or so) or even from Buck's older 440C (transitioned away in 1981-82 or so).

Something else is going on - I'd still suspect the stones being an issue, like glazing for example. If the stones were glazed, they'd essentially cease to work for most any steel at all, or become very slow at anything you try. That can actually happen pretty easily with some marginal aluminum oxide stones - especially if they've ever been used with more wear-resistant steels, even one time (steels like D2, S30V, etc). Even if the 425M blade was hardened into the 60s HRC, the aluminum oxide stones should still work for it, because the steel still doesn't have the much harder carbides in sufficient amount to make it an issue.

FortyTwoBlades' suggestion to scratch the steel with the corner of the file is a good idea. Along the same lines, you could do the same with a corner of each of your stones, assuming the corners haven't been glazed or worn at all (and they likely haven't). Even a cheap AlOx stone should scratch the steel easily, done against the corner like that.

 

[FortyTwoBlades]

I bought these Japanese files like in the photo. The blades do seem to hold an edge longer than usual. I also remember breaking the tip on the clip point blade and the sheepsfoot long ago and was surprised that they broke off.

View attachment 1821710View attachment 1821712

Hardness testing files can give mixed results for the reasons I mentioned. Failure of a file managing to bite can be caused by a number of factors, not the least of which being the mechanism by which they work relative to the surface condition of the metal. Attempting to scratch the blade surface with the tip will give a more consistent result than biting with the file teeth themselves.

 

[000Robert]

I'm also pretty sure you've got 425M at this point. The 'X' date code stamp on the blade indicates 1990 as year of manufacture. That's too far removed from the transition periods away from either 440A (Camillus, until 1985 or so) or even from Buck's older 440C (transitioned away in 1981-82 or so).

Something else is going on - I'd still suspect the stones being an issue, like glazing for example. If the stones were glazed, they'd essentially cease to work for most any steel at all, or become very slow at anything you try. That can actually happen pretty easily with some marginal aluminum oxide stones - especially if they've ever been used with more wear-resistant steels, even one time (steels like D2, S30V, etc). Even if the 425M blade was hardened into the 60s HRC, the aluminum oxide stones should still work for it, because the steel still doesn't have the much harder carbides in sufficient amount to make it an issue.

FortyTwoBlades' suggestion to scratch the steel with the corner of the file is a good idea. Along the same lines, you could do the same with a corner of each of your stones, assuming the corners haven't been glazed or worn at all (and they likely haven't). Even a cheap AlOx stone should scratch the steel easily, done against the corner like that.

The stones are pretty old so it's possible that they are glazed, although I have tried to keep them clean and oiled. But that doesn't change the fact that my 65Rc file skates across the 301's blades. It the only knife that I have that the 65Rc file doesn't bite into.

 

[000Robert]

Hardness testing files can give mixed results for the reasons I mentioned. Failure of a file managing to bite can be caused by a number of factors, not the least of which being the mechanism by which they work relative to the surface condition of the metal. Attempting to scratch the blade surface with the tip will give a more consistent result than biting with the file teeth themselves.

LOL. I've tried that also. My Buck 301 is the only knife that I have that the 65Rc file does not bite into, on all three blades.

 

[FortyTwoBlades]

Either you're failing to observe the scratches or there's something wrong with your 65 RC file because according to the data it's not possible for that steel to reach that hardness even in fully-quenched untempered state.

 

[000Robert]

Either you're failing to observe the scratches or there's something wrong with your 65 RC file because according to the data it's not possible for that steel to reach that hardness even in fully-quenched untempered state.

Maybe it's a different steel. I made no mistake - I used a microscope and couldn't see any scratches. I know how crazy it sounds. I thought that it was crazy too and wondered for a minute if I was in the Twilight Zone. LOL I spent all day on it and couldn't sharpen it until I went to the store and bought my DMT. It sharpened right up then.
My 65Rc file bites into my Carothers knives and the rest of my knives except for the Buck 301.

 

[Obsessed with Edges]

I bought these Japanese files like in the photo. The blades do seem to hold an edge longer than usual. I also remember breaking the tip on the clip point blade and the sheepsfoot long ago and was surprised that they broke off.

View attachment 1821710View attachment 1821712

Just another thought, to eliminate one unknown variable (to me anyway)...

May seem obvious, and I apologize if you've already done it. But have you tested the other files in the set against the same knife? I'm wondering if there's an issue with the 65 RC file itself, if it's not as hard as rated. Assuming the blades are in fact 425M, I still think it's unlikely they could even be hardened to something beyond 65 HRC, due simply to the limitations of the steel's elemental makeup (not enough carbon to go that high, by heat treat).

I think Buck did have a history, to some degree anyway, of taking their older blades up to hardness values that eventually resulted in broken blades - maybe a little too hard for their own good. I have this perception as a result of seeing (online) a lot of their older 440C blades and maybe later versions with broken tips. Seemed to be especially prevalent in older Buck 110/112 blades in particular.

 

[000Robert]

Just another thought, to eliminate one unknown variable (to me anyway)...

May seem obvious, and I apologize if you've already done it. But have you tested the other files in the set against the same knife? I'm wondering if there's an issue with the 65 RC file itself, if it's not as hard as rated.

Yep, I have.

 

[murat1983]

My Chosera stones sharpen S30V and S90V knives just fine. However, when I use my CBN stones the result is noticeably better.