Patina....forced on Case cv steel

C

clockman

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Jan 14, 2009
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I just got a couple of nice Case single blade trappers with liner locks with cv steel.
I've been keeping oil on them and have done very little cutting with either of them.
The one I've been using already has a few spots on the blade. Keeping oil on the blade
is a real pain.

I want a patina on the blade to avoid keeping oil on the blade all the time.
Anyone have a method they've used to get a patina on Case cv steel?

I read in a review on Case with cv to put the blade in a potato for 30-60 minutes to force
a patina. I don't eat potatoes.
 
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clockman said:
I don't eat potatoes.
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Potatoes can aggravate arthritis in some people. Luckily I don't happen to be one of them.

But yes I just received a CV Trapper today and am looking for the same info.
We might want to search for "Hot Vinegar" I read about using that more than once but need the particulars. So far my fav patina medium has been fresh tomato. One gets kind of a gun metal blue with the hint of other colors on there.

I might go for something different and try the hot vinegar this time. I haven't tried that before.
 
encore
more info I found :

The CASE Sodbuster in Chestnut/cv is a very beautiful knife, I have one and onions made it blue in no time

Thanks for all the help guys! I went ahead and put my knife in vinigar this afternoon for about 15 minutes. Ended up nice but extremely dark, kind of hope it lightens up a bit. One person said here the patina would change over time and use so I just decided to put a little but on there now to get it even and help with the rust issue. Very excited to have this knife in my pocket, slim and easy to carry but has one beast of a blade, really nice to use.

Much of that dark oxide is loosely-bound on the steel, and can be scrubbed off with some baking soda (use a paper towel & some water with it). The light grey remaining, after the really black stuff comes off, is all that's really needed for a protective oxide layer. Given some additional time, that'll also darken up a little bit more.

My 6375 CV stockman is pictured below, done with a 50/50 mix of vinegar and HOT water (~170°F or so) by dipping the blade into the hot mix for a minute or two at a time, maybe repeating that 3 or 4 times. When done with that, the blade was BLACK, and I scrubbed the loose stuff off with baking soda, leaving it as it looks here (after stropping, which brightened up the edge):

[the photo could not be viewed due to it being in photo phlucket]

However there are some photos and more info about a natural patina over time using fruit.

http://www.bladeforums.com/threads/new-knife-forced-patina-vs-natural.1304195/page-2#post-14960062

I'm going for hot vinegar. I wonder why one would dilute it with water rather than use it full strength ?
 
The darkness of the patina, after the vinegar treatment, can be lightened up to a more even grey by scrubbing the blade with some baking soda afterward. See the pic below, of my 6375 CV stockman, treated as such. I generally do this anyway with mine, to neutralize any leftover acid. I've patinated my 1095 Schrade blades and Case CV blades with a 50/50 mix of white vinegar (5%) and hot water (~170-180°F). Just dipped & held the blades in the hot mixture, and watched the patina form before my eyes in maybe ~5 minutes' time, to a very dark, almost BLACK finish. The really dark oxide is generally weakly-bound to the steel, so it comes off pretty easily.

9KfJq2j.jpg


BTW, as to why(?) I'd mix the vinegar with water, I did this as a matter of convenience while de-scaling my coffee maker, using the mfr's suggested guidelines for that (which was a mix of 5% vinegar and water). De-scaled the coffee maker and patinated my knives at the same time, dipping the blades into it after the mix drains into the carafe (at around ~170-180°F, as heated by the coffee maker). Sort of a two-fer combo job, in getting the most out of my vinegar and my time spent. ;)


David
 
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Obsessed with Edges said:
BTW, as to why(?) I'd mix the vinegar with water, I did this as a matter of convenience while de-scaling my coffee maker, using the mfr's suggested guidelines for that (which was a mix of 5% vinegar and water). De-scaled the coffee maker and patinated my knives at the same time, dipping the blades into it after the mix drains into the carafe (at around ~170-180°F, as heated by the coffee maker). Sort of a two-fer combo job, in getting the most out of my vinegar and my time spent. ;)
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Thanks
Heads up for anyone reading this the really cool guy version is over in The Traditionals Forum. There are a good number of people contributing to this same exact thread (duplicated there).

Yes last night I tried full strength with vinegar heated in a double boiler in a tiny jar and dipped part of a trapper CV blade. Then I diluted the vinegar roughly by 50% with tap water and dipped the blade in further. There was still considerable bubbling/reaction and if anything the undipped section of the blade (above the area dipped in the full strength) was even darker and perhaps a bit more tenacious once rinsed off and rubbed with a dry cloth.

Black smiths rub bee's wax on blackened iron to protect and improve the look of the black surface. I tried this on the blade and it seemed to take off more of the patina than the unwaxed section. They heat the steel or put on the wax while quite hot. This would have ruined the temper so obviously I didn't go there.

From the above I am starting to appreciate the patina that comes from food. The patina from food does seem to be more tenacious.
 
I forced patina with vinegar, I broke
clockman said:
I just got a couple of nice Case single blade trappers with liner locks with cv steel.
I've been keeping oil on them and have done very little cutting with either of them.
The one I've been using already has a few spots on the blade. Keeping oil on the blade
is a real pain.

I want a patina on the blade to avoid keeping oil on the blade all the time.
Anyone have a method they've used to get a patina on Case cv steel?

I read in a review on Case with cv to put the blade in a potato for 30-60 minutes to force
a patina. I don't eat potatoes.
Click to expand...
I use H2O vinegar mix, but you have to watch the time. You will break the two end spring. I sent mine off they replaced it, but I'm not a collector I use my knives.
 
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