Favorite forced DARK patina

gamma_nyc

gamma_nyc

Gold Member
Joined
Dec 1, 2007
Messages
713
Hi,

For 80crv2 blades, like my Winkler Contingency, what is a good way to force a dark patina? Most of the coating has worn off and I made the mistake (?) of cutting a sandwich (mustard?)….now I have a blob of dark patina on just part of the blade….

Is more mustard the way to go?

Thanks!
 
I think Winkler uses Caswell products to get that dark black. You can buy Caswell black oxide kits, but may not be cost effective for one knife. Mustard will work and has worked for many people, but it's harder to get an even coat so you get blotches.
 
Warm vinegar can achieve a very uniform black oxide layer, let the blade sit in the warm vinegar for 5 to 10min, take it out, rinse with water and wipe down with paper towel and then repeat until it's the color you'd like. The finish will wear off with use, but can be easily reapplied.
 
Thanks guys!

Is there a way to attempt a uniform, dark patina, without having to submerge the whole knife in vinegar?

Basically, I have nice shiny edges and want to keep them : )

Is there an option that is thicker consistency (eg mustard) that I could brush onto the blade and let sit, then remove?
 
gamma_nyc said:
Thanks guys!

Is there a way to attempt a uniform, dark patina, without having to submerge the whole knife in vinegar?

Basically, I have nice shiny edges and want to keep them : )

Is there an option that is thicker consistency (eg mustard) that I could brush onto the blade and let sit, then remove?
Click to expand...

You can try putting nail polish on the edge, but I don't think you are going to be even at all..... Just do the hot vinegar.... Then once you like how dark it is, strop or sharpen it
 
gamma_nyc said:
Is there a way to attempt a uniform, dark patina, without having to submerge the whole knife in vinegar?
Click to expand...
This is the method I used to put a vinegar patina finish on a KaBar fixed blade knife. Jump ahead to 17:55, to see the vinegar patina method. It worked fine, but is certainly not a "uniform" finish. The blade has some character, now. 🤣 I think all I did to shine up the beveled edge afterwards, was to strop it. But I can't remember for sure.



Edit to add: Here we go....After I took this picture, I stripped the pommel, and put the same vinegar patina on it, too.

original.jpg
 
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A google search of "M4 patina" turned up a page here (but now I can't find that page again; at least I think it was here) where someone talked about using ferric chloride to patina/etch/stain a Spyderco M4 blade with ferric chloride, and the knife looked good in the photo, so I searched online for "ferric chloride" and it looks like it's not too hard to make: Basically you soak some iron/steel in HCl (toilet cleaner in hard-water areas is commonly HCl) for a day or two, then oxidize that solution either by adding peroxide or bubbling air through it with a fish tank pump (or just leaving the stuff in an open jar, though that will take longer; there are YT videos on how to make ferric chloride), then apply it to your thoroughly degreased knife blade ... personally, I plan to coat the edge first with molten candle wax...and, since ferric chloride is mildly acidic, I will be sure to neutralize any residue with ammonia or some other base afterwards...
 
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Cementite said:
A google search of "M4 patina" turned up a page here (but now I can't find that page again; at least I think it was here) where someone talked about using ferric chloride to patina/etch/stain a Spyderco M4 blade with ferric chloride, and the knife looked good in the photo, so I searched online for "ferric chloride" and it looks like it's not too hard to make: Basically you soak some iron/steel in HCl (toilet cleaner in hard-water areas is commonly HCl) for a day or two, then oxidize that solution either by adding peroxide or bubbling air through it with a fish tank pump (or just leaving the stuff in an open jar, though that will take longer; there are YT videos on how to make ferric chloride), then apply it to your thoroughly degreased knife blade ... personally, I plan to coat the edge first with molten candle wax...and, since ferric chloride is mildly acidic, I will be sure to neutralize any residue with ammonia or some other base afterwards...
Click to expand...

It is much simpler to just buy it premade. "MG Chemicals 415 Ferric Chloride liquid" And coat what you don't want etched with nail polish. All you need is baking soda water to neutralize. You seem to really be over complicating things.

Here is an S35vn blade I etched a little while back.
Before (green is nail polish)
REWrkXLl.jpg


After
4gyyEibl.jpg

ddNTL0fl.jpg
 
gamma_nyc said:
Thanks guys!

Is there a way to attempt a uniform, dark patina, without having to submerge the whole knife in vinegar?

Basically, I have nice shiny edges and want to keep them : )

Is there an option that is thicker consistency (eg mustard) that I could brush onto the blade and let sit, then remove?
Click to expand...
Tomato paste can be spread easily and can be distributed on a blade pretty consistently/evenly. Works fast, like other acids (vinegar and citrus).
 
Bdtry said:
You seem to really be over complicating things.
Click to expand...
Nah, just a cheapskate, mad scientist and retiree with too much time on my hands...given the choice between either making something or buying it, I'll usually choose the former ... and for $20 I suspect I could make a barrel of the stuff out of crap I already have lying around the shop.

Plus I'll learn something, although it looks about as complicated to make as coffee with cream and sugar.
 
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I have used Coca Cola with good results. The usual process of soak, scrub off the loose oxides and soak again. Repeat with longer and longer soaks until the Coke no longer fizzes and then change the Cokke and repeat until you are happy with the results. Coke is cheap, easily obtained and not dangerous. I do this at my kitchen sink.
 
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