Need help with black spots on my Case knife.

[colekmiller11]

I carried my Case XX moose in my carhartt breast pocket for 2 days and when I pulled it out today, the bladesw had black spots all over them.I'm worried that it might be a more serious form of rust, because it doesn't look like a normal patina.I see these spots on alot of older blades too. I can't get them off for the life of me. Should I be worried? Does anyone else have experience with these? If so, any way to remove them?

 

[Woodrow F Call]

Pics might be useful.

 

[colekmiller11]

Pics might be useful.

 

[67nick]

I've got a case congress with the same corrosion issue. Never had much luck removing the spots entirely, though Flitz will lighten them.

 

[TLARbb]

That appears to be minor pitting. It is almost inevitable on a user. Your knife is obviously being used for the things a knife was intended to do. Just watch it and keep it clean and you should be okay. Those are probably due to some kind of mildly corrosive materials that came in contact with the steel.

At this point I wouldn't be worried. If you are seeing red rust forming, then you might need to use a preservative type lube on the knife (but not if you use it for food). Break free is a good preservative type lubricant. Mineral oil (USP grade) is okay for foods, but not as good as a preservative/rust preventer. The most important thing is to figure out what is causing it and develop an action plan based on the cause.

You do not have a serious problem at this point based on your photos.

Ed J

 

[Obsessed with Edges]

So long as the spots are actually black (or grey), I wouldn't worry too much. Use a magnifier with bright light to look for any red (sometimes some red will 'hide' in the black spots). The black oxide won't harm the steel like red rust will. In fact, black oxide will somewhat reduce the chances of rust forming in those areas; it's a protective oxide layer (patina). If you want to eliminate the pitting, you'll need to sand the steel smooth again. For a using knife, I don't think that'd be worth the trouble.

You could polish the blade with Flitz/Simichrome. It would remove the patina entirely from the blade, without fixing any of the pitting. No harm in that, but you want to decide if you'd like to keep the patina or not (I'd keep it, personally).


David

 

[Nixelplix]

I don't mind a few spots on my knife. It gives it character. The scrubby part on a dish sponge seems to lighten them up a bit.

 

[Fanglekai]

If you force a patina it will help prevent active rust. The patina will still change over time but it's nice to start a base layer to help protect against rust. You could polish it up with flitz first to remove most of the rust and patina and start fresh if you want.

 

[Will Power]

Well, patina is rust of sorts, just a less menacing type! The black spots are the precursor to an overall darker colour as seen on the Queen Heritage Woodsman.
I often give a rub down with a scotchbrite type pad, gets the black spots off, gives a matte surface and makes subsequent patination more even, in my experience anyway.

Thanks, Will

 

[Django.cj]

Perfectly normal IMO. So long as you're maintaining the blade and not getting deep pitting, you should be fine.

 

[Bigfattyt]

Looks broken. Just send it on my way.

if you want to keep it looking shiny and new, a loaded strop will work.

I like the spots.

"pepper" marks will show up on any carbon knife that gets used regularly.