As an actual knife maker, I can tell you that we typically will use Ferric Chloride and then usually coffee. If you make your coffee REALLY strong, like 2:1 water to instant coffee it will turn your blade BLACK. The key is not to wipe it after and blow it dry and then hit it with a heat gun and lightly coat it with wax. It creates a very good, durable finish that is nice and shiny and very black. You can check some of my videos and you'll see the contrast it creates.

My maximum internet fame has been reached :) To get a more uniform patina I literally cover the blade with the steak and let it sit, then move it around so that all parts of the blade are covered, then let it sit. Also the hotter the juices, the better the result seems to be. I'm really glad you gave this technique a try and that you got some good results from your testing.

I recently used sauerkraut and loved the results. I will say the way the onion purée was spread on the knife is my approach to covering the blade. Creates interesting patterns like little islands. Good video is good! Love the patina nerd content!

Coke seems to be the way for people that dont have time to let the patina build up naturally. Shake out the carbonic acid quite good and you wont have issues with those bubbles. Nice vid, I loved it. ❤

Fun fact: I gave my sink a good scrub with bar keepers friend. When I rinsed it down the drain it opened up my slow running drain. Awesome for cleaning knives and cook wear. Great multi purpose product.

Thanks for a very entertaining video ❤

I did the onion patina with my carbon steel Mora camp knife. I left the blade stuck a giant white onion over night and was left with a tiger stripe patina that was the cell walls of the onion. I also got a 300mm White #2 yanigaba and cut my dogs soft food from large sausage like tubes of food. The fat from the healthy dog food and the mainly protein cutting I’ve done with the yani has left an amazing BLUE patina on the blade.

The steak was definitely my favourite. Ultimately, I think I just enjoy the slow and natural process of the knife developing a patina from regular use. The patina feels more personal and authentic. Maybe that is why I liked the steak patina the most. Fun video. Thanks.

This is an interesting video. I'm a cooking enthusiast. I have also bought most of my fancy knvies from Knifewear. I'm separately the only medically released Canadian Armed Forces soldier to negotiate a 6 month, full-time apprenticeship as a Traditional Blacksmith. I did a proper, old-school apprenticeship in coal blacksmithing with a Master Smith for 6 months, full-time. Not just 'bladesmithing', but full on Pre-Industrial Fabrication. I fully appreciate the thousands of dollars of steel you just experimented on. Kudos for the sacrifice. Ferric Chloride is obviously the standard for producing an even 'industrial' patina on the steel. The patterns, my favorite being the onion, are cool. But I still can't help but wonder why you would 'force' a patina. And I totally get it in terms of internet culture, so-to-speak. But between being a cooking enthusiast & a formally trained blacksmith; I have to suggest that time is the only true way to express yourself honestly. It will reflect what you 'actually' do with your knife, rather than whatever fad of the day is ongoing at the time you purchase your knifewear. On the function of Science regarding forced patinas, I may suggest if you ever consider something like this again to take more metric data in a matrix. You can take the pH, primary reactive substance (vingears/acetic acid, etc) vs the composition of the steel so that you can more specifically and accurately graph your results. All in all, it was a great video. Thanks again for sacrificing that steel to test. I'll be interested in a next video in this set regardless the route you choose. Cheers.

A real easy way to put a patina on your brand new knife is to go on KZfaq, look up a video on how to patina your knife while processing food with it and leaving it sitting on the counter. Yep that worked.

This was so well presented and entertaining. I just allow my carbon knife to develop a natural patina over time through regular use.

Application method is more important than the specific type of acid you use. The most even and controlled method is to soak a long, narrow strip of paper towel so that it's all wet, but NOT dripping wet. Then FOLD it over the edge of the knife, so that it ONLY touches the cutting edge where the core carbon steel is exposed. I did this with lemon juice on a HAP40 blade for exactly 7 min, and it left a dark gray and uniform patina along the edge without affecting the stainless steel cladding at all. HAP40 is semi-stainless, so you should only need 5 min or less with something like Aogami Super, and even less with Blue 1/2.

i never force but i always get a great blue patina after cutting onions, and quickly washing and drying. i never oil my carbon blades, even my cumai blades, never get rust either (carbon) or corrosion (in the cumai stuff) great vid. i can't believe i just watched 28 mins of this lol.

Top tip regarding the coffee & water technique. I was hanging my bushcraft knife with curly birch handle, and for some reason the edge of the handle got in contact with the coffee mixture... Well, the handle split and twisted on the edge... Gutted. Brand new knife. Anyway...

Those munestoshi's punch way above their weight. I have one of these and it's probably my most used knife. I have a bunch of way more expensive knives. But, the santoku cuts like nothing else. Food releases insane. There's zero drag. Especially those horizontal cuts through onions that a lot of other nights struggle with.

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Bacon works but it's in the long run. I'm cutting between two to three 5kg boxes of bacon per week and within the first month of using my white steel gyuto it started to get really Nice shades of blue. Also cutting lemon confit leaves really dark shades on your knife

I think the Coke needs to be flat. Leave the bottle open for a couple days prior, I bet the bubble marks would be gone. Side by side, I think the Coke finish looks slightly better than the coffee if you can get rid of the bubbles. That's my two cents!

If you want a look, try a grainy mustard, let it sit for a few minutes for it to start to work and then wipe off excess. If you like the look, then keep it. All of these are just for a very temporary look, because you literally cut anything reactive, and it changes it. This works better on pocket knives, like an Opinel. It only puts a surface on it that you can wipe off with a mild abrasive with little effort. So don't get attached to the look.

I worked in Yardbird and my choice of knife is a Aogami 2 Kitaoka Honesuki. During the 3 hours duration of cutting chicken nonestop, it develops a fairly decent layer of patina! Can try chicken fat next time

Is there’s a way you can remove the black paint on the knives like Masakage Koishi and Fujimoto Hammer Tone?! Thanks

The reason I would say that the drain cleaner did not work is because it is composed of Sodium Hydroxide which is alkaline as opposed to acidic

Do you know if Masamune kitchen knives from kamakura are any good?

YEAH DUDE!!!!

Is there any way of stopping onions from turning brown I use a carbon steel knife.

Did you use a strong 35% Vinegar or a more normal 3.5% - 12%?

My go to is steak/onion. It's probably just me, but I've felt like steak has worked better for Aogami and Onion better for Shirogami. There is only one more thing to try and that would be the Nekonoshoben method which has reached mythical reputation. Is it a scam? Is it the secret technique to most amazing patina? Who knows ;)

Try with red onion!

Look mom, I'm on TV!!! 😁

Smoked and juicey ham, dear Skye, that's the way to go for instant patina ....you can smell it as the metal reacts to the juices

White vinegar applied with toilet paper specifically has given me great results that are still random patterns

bruh my google started a timer for one hour

I find that using my knives adds patina. YMMV.

Did I miss a part where she said what type of carbon steel those knives are? Would be useful to know, with my knife collection different carbon steels seem to patina differently.

😍😍😍

Why to force it? The pleasure is to see the evolution of the patina over use and time, isn't it?

strawberries

So, I've really got to ask because I'm curious. Why doesn a full carbon blade rust so fast if not wiped off within 10 minutes or so?? Yet, you can fully submerge it in liquid (coffee) for 24 hours and it only forms a nice patina? I'm just clueless on how this does form extreme rust.

"thick, viscous..." 😅 "...a little chunky" 😨wait what

yall didn't split the chapters up. After "intro" it stays "coffee" for the remainder of the video smh my head

Omg no paint thinner in a closed room! Outside is best. So bad for you

Not putting in the effort to take care of your tools, so they develop a patina is one thing. But taking extra effort to have your tools look like you did not put in the effort of taking care of them is just silly.

I don't know how I got here and have no idea why you people are trying to make your knives ugly. 😵‍💫😵‍💫

Wow, the coke one turned out nice.