Can a blade crack on just one side?

[Skylar303]

Hey,

Just got a petty and I'm wondering if this is a stray scratch or a crack? It's only on one side of the blade.

Sorry for the eh pics, spot in question should be visable, but is near the brighter light on the edge. There a similar scratch next to it on the right that got washed out by the light in the 2nd pic, but doesn't look quite the same.

Thanks!

 

[HumbleHomeCook]

Kinda hard to tell but looks like a stray abrasive dug in.

 

[Skylar303]

Kinda hard to tell but looks like a stray abrasive dug in.

That'd be great if it's just that. How to tell other than taking it to stones? Or just seeing if it goes away?

It's not for me so I'd hate to mess with it before hand, but then again better than gifting a broken blade...

If it was a crack would the whole blade usually break and not crack? San mai blade.

Edit - Also hard for me to tell as it seems to stop right at the cladding. Or halfway in.

 

[HumbleHomeCook]

Short of messing with it, it's going to be a little tough to tell buddy. I mean they'll look pretty much the same, your nail will catch, etc.

But, that said, look how it matches exactly the grind marks around it and how dead straight it is. Then bounce that off the law of averages. Me? I'd call it a grind mark and not worry about it.

 

[superworrier]

Agree with @HumbleHomeCook ’s assessment if you want another opinion

 

[Skylar303]

Agree with @HumbleHomeCook ’s assessment if you want another opinion

Thanks for the reassurance. forged knives are a whole different beast. (To me anyways)

 

[Mlan]

I agree with the others. Being that it goes to the edge if it was a crack you would very likely see it on both sides. If you have one looking at it with a high powered microscope may give you some visual peace of mind.

 

[HumbleHomeCook]

Further, it looks like it runs through the core and clad steels. That is HIGHLY unlikely for a crack. Especially to not have more evidence.

 

[Heckel7302]

Agree with Humble. Merely a flesh wound.

 

[refcast]

So uh, I have had a decent amount of experience with cracked blades. I've crack a couple, got a couple cracked, had to diagnose if it's abrasive or a crack, etc etc. Lol

If the "crack" is only on one side, then it's a deep scratch for you're blade. I've cracked an usuba, and it ran up into the iron as well, so cracks aren't stuck to only steel.

Blades can show a crack on one side. I've had a Mizuno honyaki gyuto so that to me. Quite terrifying, lol, for the price. It was a legit crack during thinning, then disappeared. Stress crack. I've had quench cracks on single bevel knives. Cracks from me straightening. Brittle steel cracks. Cracks from a deep chip that damaged steel further up in the blade. Corrosion cracks.

Cracks like the vertical one you think you might have, they always appear at the edge. There becomes a gap in the edge, but I don't see one. So I think you're fine. Knives with vertical cracks I've handled: 1 tf 150mm gyuto which was my fault, 1 usuba also my fault, 1 deba pre cracked, 1 old 300mm yanagiba from corrosion that cracked more when I straightened, 1 forged honesuki. All these had cracks go to the very edge, where the steel is the thinnest and forces most concentrated

But even if it's not a crack, the knife is a little more weak there, so pay heed.

 

[Mlan]

So uh, I have had a decent amount of experience with cracked blades. I've crack a couple, got a couple cracked, had to diagnose if it's abrasive or a crack, etc etc. Lol

If the "crack" is only on one side, then it's a deep scratch for you're blade. I've cracked an usuba, and it ran up into the iron as well, so cracks aren't stuck to only steel.

Blades can show a crack on one side. I've had a Mizuno honyaki gyuto so that to me. Quite terrifying, lol, for the price. It was a legit crack during thinning, then disappeared. Stress crack. I've had quench cracks on single bevel knives. Cracks from me straightening. Brittle steel cracks. Cracks from a deep chip that damaged steel further up in the blade. Corrosion cracks.

Cracks like the vertical one you think you might have, they always appear at the edge. There becomes a gap in the edge, but I don't see one. So I think you're fine. Knives with vertical cracks I've handled: 1 tf 150mm gyuto which was my fault, 1 usuba also my fault, 1 deba pre cracked, 1 old 300mm yanagiba from corrosion that cracked more when I straightened, 1 forged honesuki. All these had cracks go to the very edge, where the steel is the thinnest and forces most concentrated

But even if it's not a crack, the knife is a little more weak there, so pay heed.

Did the crack on the Mizuno run to the edge?

 

[Blank Blades.]

Hey,

Just got a petty and I'm wondering if this is a stray scratch or a crack? It's only on one side of the blade.

Sorry for the eh pics, spot in question should be visable, but is near the brighter light on the edge. There a similar scratch next to it on the right that got washed out by the light in the 2nd pic, but doesn't look quite the same.

Thanks!
View attachment 250836View attachment 250837View attachment 250838

Can we get a pic of the other side?

 

[refcast]

@Mlan

It was near the heel but not close to the edge. It was like a second hamon appeared from the choil and blobbed 1cm toward the tip. The crack was 1mm-2mm and was along the new faint hamon

 

[Skylar303]

Can we get a pic of the other side?

Otherside looked clean so I didn't add it originally. Didn't have stray scratches which led me to wonder if it was cracked in shipping or something. 3rd pic is cleanest, wiped the junk off the blade edge. It was bugging me but I'm too tired to retake all the pics.

 

[HumbleHomeCook]

View attachment 250838

Look close at this pic buddy. Right at the very edge it looks to me like you can see a bulge. That would further indicate a scratch/deformation and not a crack.

 

[Skylar303]

Look close at this pic buddy. Right at the very edge it looks to me like you can see a bulge. That would further indicate a scratch/deformation and not a crack.

Yeah pretty sure it wasn't a crack after the first few responses. But guy asked for pic of the otherside... The bulge look might be weird light or a bad camera also heh.

 

[Blank Blades.]

Hard to tell. But if this is on that same spot it could possibly be a crack.

But. At the same time it could just be a scratch. If you wanted to find out. You could gently flex the part of the blade.

Not enough to permanently deform, or break it. Just barely enough to see how the area moves. If its a crack you will be able to tell likely.

Or like others have mentioned. You can probably ignore it. And just keep using it. Since it likely will be on.

 

[Skylar303]

Hard to tell. But if this is on that same spot it could possibly be a crack. View attachment 250981

But. At the same time it could just be a scratch. If you wanted to find out. You could gently flex the part of the blade.

Not enough to permanently deform, or break it. Just barely enough to see how the area moves. If its a crack you will be able to tell likely.

Or like others have mentioned. You can probably ignore it. And just keep using it. Since it likely will be on.

I just checked again and it's only on the one side. The area on the cleaner side that lines up with the spot in question is uniform with no strays.

So I think it's just a deeper groove. Just the lack of them on other blade and the otherside of the one in question led to the OP question.

 

[TB_London]

Deep scratch - I’d smooth it out as I’ve edge tested blades at 36g before and they’re more likely to crack than when at 400g as the deep scratches seem to act like stress risers. But that’s when being intentionally abusive