Acid Etching, Vinegar/Mustard & Bleach Patinas

[Moin.]

Oh! You can also use Pottasium Permangnate KMnO4. Availability should not be a problem. A strong oxidizer and leaves pretty strong stains on metal and near about on any surface.

Also try Alum.

In the traditional way of finishing Faulad and Sankela blades some craftsmen also use Amla and Ritha but the only difference here is that the "patina" / Jauhar is inherently present in that case.

Thanks Rajat; Finding Nitric Acid and Potassium Permanganate is not so easy. Not available in the local Baniya Shops I guess with these kinds of modern steels Alum, Ritha etc with its very mild acidity will not works. I've dippes the Nieto now in the Bleaching Powder Bath for more than 30 mins, not a spot whereas the cheap folder was oxidised in 5 mins. 440c is showing some very good corrosion resistance.... I can only imagine how good S30V & other exotic metallurgical concoctions would be..

[Moin.]

You've probably thought of this already, but do make sure all of this process is done in a very well ventilated area - balcony, terrace, backyard etc. would be ideal. Will keep you & yours safe from the fumes and most certainly save you a tongue lashing from the better half as well...

Cheers!
Abhijeet

Thanks Abhijeet. Iam near a window and wearing latex gloves while handling acids and bleach. No eye protection or gas mask handy as of now, but I am careful. No better half yet, single and ready to mingle. , my mother india usually let's me be when I am around knifes and swords. She's used to this by now.

Regards
Moin.

[mundaire]

KMnO4 (potassium permanganate) can be picked up at any chemists/ drug store. It has many uses (anti-fungal, disinfecting fresh produce, purifying water in an emergency, etc.) and used to be included in any decently put together first aid box, though not so often these days (I always pack some in my first aid kit).

Combine it with a few drops of car coolant if you want to see an interesting chemical reaction The reaction is exothermic (produces a lot of heat) and is best conducted outdoors and away from anything flammable.

Cheers!
Abhijeet

[Rajat]

Finding Nitric Acid and Potassium Permanganate is not so easy.

Nitric acid may not be easily available but Potassium Permangnate is very easily available. Even at local baniya shops or at medical stores as it has several household uses. While it may not corrode the sophisticated baldes but it will definitely mark / stain them giving a temporary patina which may be rubbed off with some scotch brite.

I guess with these kinds of modern steels Alum, Ritha etc with its very mild acidity will not works.

No these are just meant to impart a dark colour and not really to corrode

how good S30V & other exotic metallurgical concoctions would be..

Some time back I had filed off a part of a knife to improve the grip and make it comfortable to hold. It was made out of S30V, black finished blade. I later tried to finish the filed part black with a strong blackening agent but it was totally ineffective.

[Moin.]

Satisfied at last, after about 45 mins in the Bleaching Powder Bath took our the blade and rubbed it all over with scotch brite. It's now got a lovely and a very consistent pitting pattern. Next step is a dip in hot vinegar to blacken it and then polishing the raised bits with 1200 grit polish paper.

More than 45 mins in strong bleaching powder, not a spot on the Nieto...

[Rajat]

[Rajat]

Combine it with a few drops of car coolant if you want to see an interesting chemical reaction The reaction is exothermic (produces a lot of heat) and is best conducted outdoors and away from anything flammable.

Ok, I will give you a couple more

Mix Potassium Permangnate and common sugar (preferably powdered) add water and stir and see what happens

Check out a mixture of Glycerin and Potassium Permangnate

Wear eye and hand protection, do not stand close to it, do not do it indoors, do not hold the container in which you do it in your hands and do not hold me responsible

[Moin.]

Done deal, the blade became deep grey after a bath in boiling white vinegar,( used mum's copper bottomed pan as she was out shopping . Too dark to my liking. Cleaned the blade under running water with soap. Polishied it with a few strokes of 1200 grit polish paper.

P.S: Almost two hours in bleach, not a damn spot on the nieto....

[Moin.]

Abhijeet and Rajat, you two are getting into very dangerous territory

[Moin.]

Dipped the Nieto into Conc. HCl for 3 flat hours, not a spot of oxidation. Like a fool in desperation dipped the blade in hot vinegar forgetting the wax coating. By the time the wax melted in boiling vinegar got a faint Hamon line on t he blade. Have a crappy camera, so pardon the pics.





I'bve now decided to try & corrode the 440C surface, will try and source Conc. Nitric Acid as suggested by Rajat.

Regards
Moin.

[Moin.]

My hands are all sore from all the filing done over the week end so thougt of experimenting with forced patinas.

The first is the Kiridashi blade which is now my EDC *Thank you Marthandan ). It is so sleek and convinient to carry in a formal office trouser. Boiled some whote vinegar and dipped it in for that deep grey patina. It is made from a file which is hard tool steel, should patina well

The second is the Rough Rider Blade.I've put in a very nice polished edge on this knife which I wanted to show, rubbed a wax candle slightly on the edge. A pice of soft cotton cloth was tied to the blade and was then soaked with white vinegar. Want to see how the pattern turns out, instead of dipping the blade in vinegar and getting a uniform grey finish on the blade.

This is how the knife looks right now.

[essdee1972]

Lagey Raho Moin bhai!!! Seems you are on summer vacations and enjoying every moment!! By the way, yeh POOJA kaun hai??

You can also try Rustoleum. It's supposed to be a rust remover, but since it is hydrofluoric acid (HF), would cause oxidation. You MUST (must must must) wear hand protection for this. I got mine from Home Town outlet in Vikhroli, Mumbai. For a very strong corroder, you can try to make aqua regia - 3 parts HCl to one part HNO3. (warning! achtung! khatra!)

Instead of wax, you might try to coat with varnish / wood art kind of products. Need to check whether they will hold up to the strong acids, say by coating a clean nail with varnish and dropping in the acid! If they do, you might have a (slightly) better control on the pattern, as you can apply the varnish with brush / finger.

You are giving me ideas again, but with a kid and a dog, can't be playing around with dangerous liquids!! I'll still try to "do" the WBTDC Khuks with the Rustoleum......

[Moin.]

After a full nights dip in Whte Vinegar, nothing on the Rough Rider, 440C is holding up very well, survived 3 hours dip in HCL and a full night in White Vinegar without any corrosion or patina on the blade. The Kiridhashi got a lovely deep grey shade.

P.S Essdee: Kaun Pooja No Summer Holidays, just the khujli to try something out therefore all these experiments.

[Moin.]

Lagey Raho Moin bhai!!! Seems you are on summer vacations and enjoying every moment!! By the way, yeh POOJA kaun hai??

You can also try Rustoleum. It's supposed to be a rust remover, but since it is hydrofluoric acid (HF), would cause oxidation. You MUST (must must must) wear hand protection for this. I got mine from Home Town outlet in Vikhroli, Mumbai. For a very strong corroder, you can try to make aqua regia - 3 parts HCl to one part HNO3. (warning! achtung! khatra!)

Instead of wax, you might try to coat with varnish / wood art kind of products. Need to check whether they will hold up to the strong acids, say by coating a clean nail with varnish and dropping in the acid! If they do, you might have a (slightly) better control on the pattern, as you can apply the varnish with brush / finger.

You are giving me ideas again, but with a kid and a dog, can't be playing around with dangerous liquids!! I'll still try to "do" the WBTDC Khuks with the Rustoleum......

I am trying to source Nitric Acid, but no luck as of now. This Home Town Outlet seems to be a must see place..........

P.S: aqua regia I want slight oxidation on the blade, not dissolve it completely...

P.S:02: Post pics of your blade and your Rott.

Regards
Moin

[ak27]

No Summer Holidays, just the khujli to try something out

The ITCH to ETCH, eh??

Seriously sir, the commitment you show and the way you shell out time for doing all this stuff is amazing!!

And needless to mention, that khujli of yours is seriously contagious!! I have dipped my Meula M5161 in a thick milky solution of bleaching powder over-the-night and the blade didn't quiver. I guess the Inox SS is to blame. Will try it out on a cheaper blade today.

Waiting for an update on Khuk mod.