What are these lines?

[StrangeDaze]

i took out my stripped and patina’d bk4 today and notice some strange lines

Are these lines from the manufacturing process? I thought maybe they were from
The patina but i tried scrubbing them off and they are still there. I doubt hey are fractures as i cant feel them with my finger nail and just went out and chopped on some big bay stumps and i dont think they grew. Just curious if other people have experienced these lines and what they might be.

 

[daizee]

That's uh... huh.

 

[The Warrior]

That's a new one on me. Doesn't look right, fo sho.

 

[91bravo]

It looks like mill scale to me. It's part of the quenching process. I could be wrong though.

 

[StrangeDaze]

That's uh... huh.

That's a new one on me. Doesn't look right, fo sho.

Im at least glad im not the only one who thinks its weird! I thought i could be too myopic.

Not quite sure but upon closer inspection it looks like one of the lines might run onto the edge, its too close up for me to capture on camera though.

 

[The Warrior]

It doesn't look like cracks to me, but how or why or what the hell they are, I have no idea, haha.

Maybe the next time @Ethan Becker is here, he can address it.

 

[eveled]

If you are talking about the fine parallel lines that cover the whole blade. They are from the final machining process. When they know a blade will be coated they aren’t picky about the final surface.

If anything the rough surface helps the coating stick.

 

[kvaughn]

One of them looks like a very fine crack.--KV

 

[StrangeDaze]

If you are talking about the fine parallel lines that cover the whole blade. They are from the final machining process. When they know a blade will be coated they aren’t picky about the final surface.

I know those are machining marks and am fine with them. I am talking about the weird zig zaggy, oddly shaped lines.

 

[kvaughn]

I know those are machining marks and am fine with them. I am talking about the weird zig zaggy, oddly shaped lines.

Me too.--KV

 

[StrangeDaze]

Me too.--KV

My last post was for eveled

Thanks for the input about the fine crack though. I honestly cant tell if they are cracks or not or what they could be. Like The Warrior said hopefully @Ethan Becker can take a look the next time he drops in or maybe @OFFICIAL_KA-BAR even.

 

[91bravo]

I betcha those lines are where they cleaned the mill scale off the raw blade.

 

[eveled]

Gotcha. Those are weird lookin. Somehow I looked past those and focused on the fine lines. Like looking through a window screen I guess?

 

[1066vik]

I betcha those lines are where they cleaned the mill scale off the raw blade.

that's my guess, too.

 

[Xr6x]

Never seen lines like that before. They don't look like cracks. What did you use to patina it . I was wondering if it might be how whatever you used dried on the blade ?

 

[StrangeDaze]

Never seen lines like that before. They don't look like cracks. What did you use to patina it . I was wondering if it might be how whatever you used dried on the blade ?

I just used white vinegar. I can’t remember if i soaked it or wrapped it in a soaked paper towel. I tried both but i think the last time i did it it was soaked in a paint roller tin. I tried scrubbing off the patina in a spot with a line but nothing happened.

 

[Xr6x]

I just used white vinegar. I can’t remember if i soaked it or wrapped it in a soaked paper towel. I tried both but i think the last time i did it it was soaked in a paint roller tin. I tried scrubbing off the patina in a spot with a line but nothing happened.

Oh well you got some cool designs on your blade

 

[JJ_Colt45]

can you catch your fingernail in any of it anywhere? if they were cracks showing like that they should be big enough you could feel it ...

I'd lean more towards as a couple people mentioned ... just from cleaning scale off ...

 

[Xr6x]

I betcha those lines are where they cleaned the mill scale off the raw blade.

You very well could be right but I was just wondering wouldn't the grinding process remove any and all scale ?

 

[StrangeDaze]

can you catch your fingernail in any of it anywhere? if they were cracks showing like that they should be big enough you could feel it ...

I'd lean more towards as a couple people mentioned ... just from cleaning scale off ...

In my original post i say that i cant feel it with my fingernail which is why i doubt they are cracks.

You very well could be right but I was just wondering wouldn't the grinding process remove any and all scale ?

I thought the same thing but considered they probably grind that bevel pre heat treat but i could be wrong. The patterns definitely remind me of scale. If thats the case its kind of cool, i’ve just never seen anything like it before and it appears i’m not alone.