Just saw the thread.

Coffee etch is the latest rage in knifemaking. Before that it was "baked on brown or black lacquer".
I find ferric to be as good as one gets on wootz and some old wootz etches better than others. Some prefer nitric. Both used in very dilute forms.
Some come away very black with ferric and others whiteish. I assume it is slight internal chemistries which cause the coloration variables. Heat treatment does play a part as well and the cause of most etching coloration issues within a single bar as with the blades shown above in the thread.

I have not found the carbides to go away till high into the bright orange colors when forging and even then you can bring them back if you further play with heat. As we have all seen the weld joints on Indian blades show a black weld line and white on either side and then pattern as we expect. I promise you that those have reached a full welding temp when they are made....or repaired...the jury is still out on why they have those welds...the record I have seen was a Tulwar in Jodhpur, India with three welds...meaning four pieces.

I will shortly begin a project which will have several wootz welds. No need to post it here as it is modern material all around.

Ric

I'd not recommend experimenting with it. It could work or it could damage the blade. Good wootz will react to most mild etchants like lemon juice or any household cleaning solution containing acid (like muriatic acid), I heard even Coca-Cola and coffee do the job although never tried them as I use FeCl and also generic household cleaner containing muriatic acid... whatever darkens the steel without potential to damage it.

Sorry to revive this thread but I have been attempting to etch an old Turkish Pala and have had a couple of issues that maybe you guys can answer.

I have now tried both 2% nital and ferric chloride. The nital seems superior as it does not rust as quickly, but as others have pointed out it is very non-uniform in its etch. I apply with a paintbrush. I've also tried applying with cotton pads but it doesn't seem to work as well.

Ferric chloride mixed 5:1 almost immediately rusts the blade, prior to even bringing out any pattern. So it has been retired from use.

I have been mixing a large amount of baking soda with water but it seems ineffective in neutralizing the acid. Though from what I have read it seems you guys are rinsing the blade and rubbing baking soda directly onto the blade if I read that correctly? So not mixing it prior.

Finally, I'd like some more info on the instant coffee method, are you simply leaving the blade in water mixed with instant coffee for many hours? Seems like there is good feedback on this method and I'd like to give it a go.

Regards,
Jack

JT88, it sounds as though your ferric chloride solution is too strong. I would suggest a 1:20 solution of FeCl3 in water and see how that works for you. It may take several minutes to bring out a pattern but you should be less likely to go straight to rust. Warming the blade can accelerate the process when using milder solutions.

A lot of this is trial and error. Fortunately the blade can always be repolished and one can start over.

Thanks for the response after reviving a long dead thread.

I did dilute it more last night and give it another go, looks pretty decent now. Still a bit of a brown tinge overall, but not too much. Wondering if stop now or keep trying to go darker.

I am still very curious about trying instant coffee, one of the other posters said they would do it after using ferric chloride. Hope they will respond with a process for it.

Has been an exhaustive process, many re-starts. I think the pattern looks better now than when I got it, but less uniform overall.

i think it looks good. It is hard to get good results with ferric. As for the instant coffe. I had som good results etching pattern welded, but never wootz.
You could try vineger, or a lemon. Takes a long time but I find it easier to use then ferric. Every blade is unique so you never know what will get you the best result.

Believe it or not "Lea and Perrins Worcester Sauce" works on Wootz. Recommended to me by a retired museum conservator, and it worked for me on an old blade quite nicely.
There are other brands, but I have not tried them.

What method do you use with Worcester sauce? Can’t believe I’m asking that 😂

Hello Battara. Is this for cleaning the blade after etching? I also use it but I mix it with water then wipe the blade after etching. I haven't tried putting the baking soda directly on the blade. Should I let the baking soda sit for a number of minutes? Thank you

This is just for after the etching and to stop the etch ing process. You can leave it there for a couple of seconds to minutes, and then take the solution of water ad baking soda off.

Thank you very much!

You just paint or splash it on. It's no odder than instant coffee. It's a slow etch and needs renewing as it loses strength, but it does give results, is easily available and does not need special precautions. Rinse off when/if you get the result you want and oil the blade.

What kind of timeline are you talking about for the application? May give it a try.

I'm not going to say anything about wootz, I do not understand the material, and I do not know how to recognise the types nor how to etch & stain them.

But I do understand mechanical damascus and Malay World pamor. I have made quite a lot of both, and cleaned, etched and stained quite a lot of both, and I have been doing this with both recently made & historic material for a very long time.

The damascus I have made myself I have usually stained with ferric chloride, just the pre-prepared mix that is used for etching circuit boards. Yes, it can be difficult to achieve a satisfactory result with it. I apply with an old soft toothbrush, over the laundry tub, with the cold water tap running. I rinse off, dry, and reapply until I get the colour I want, then I paint on a slurry of bicarb of soda, let it sit for a few minutes, thoroughly rinse, dry with a lint free cloth, then a hairdryer. Spray with WD40.

On damascus I have used various other acidic solutions, but overall I have achieved the best results with ferric chloride.

On historic mechanical damascus, and on pamor --- which is essentially mechanical damascus sometimes with a nickel content --- I usually use laboratory quality white arsenic mixed as a paste with fresh Tahitian lime juice.

Let me be very clear:- I do not recommend that anybody without proper training and permits attempt to play with any kind of arsenic.

On just about any ferric material I am a big fan of white household vinegar. It cleans things beautifully and on some materials it will impart some degree of stain.

Does any one else find that this tarnishes the finish. I have been using the Hrisoulas' method of polishing with a leather hand buff, cerium oxide, and water to make it pop again. I have noticed that I often dull my edges a bit if they are functionally sharp with the hand buff. Anyone else have this problem or a better technique to suggest? Has anyone tried a block with a pad on it under the leather buff to control it's interaction with the edge more?

For the last 10 years I have used exclusively Nital 4% for etching wootz.

Now I have run out of Nital and as it proves to be almost impossible to get in Europe, I had to switch to Ferric Chloride.

Recently, I etched the first blade with ferric chloride and got very good results, comparable with what I usually got with Nital.

Here are the steps I had followed:

1. Polished the blade up to mirror finish (grit 2500).

2. Cleaned the blade thoroughly with white spirit.

3. Etched the blade with ferric chloride (about 30%) by swapping it with cotton swabs soaked in the solution. Applied it uniformly with repeated, even and fairly quick passes to make sure the solution is evenly applied on the whole surface. I changed the swabs a few times and carried out this process for 3-4 minutes, until I got a uniform, dark patina.

4. Rinsed the blade thoroughly under flowing water.

5. Dried the blade with toilet paper and hair drier (on low heat).

6. Left the blade for 24 hours to completely dry out and continue the oxidation process.

7. Cleaned the residual golden oxidation that appeared in parts with very gentle passes of cotton swabs with Pre-Lim.

8. Cleaned the blade with white spirit and let it dry for 24 hours.

9. Applied protective layer of Renaissance Wax.

PS: Unfortunately, in my opinion instant coffee has very limited applicability. For instant coffee to work, it needs very long times, and the blade has to be immersed in the solution. This works fine for an unmounted blade not for a fully mounted knife, because you cannot fully immerse in coffee the whole knife/sword for hours without risking catastrophic damage to the hilt and mounts. And if you don't fully immerse the whole knife/sword you will end up with completely unetched spots around the front bolster/ricasso.

I will only add one more thing - Turkish wootz does not pop out like Persian or Indian wootz. This pala might be Turkish wootz.

I think I might know why coffee gives dark black wootz lines.
Coffee is acidic and oxidizes ( rusts) areas with higher content of carbon. But at the same time it contains tannins that convert rust into permanent black Fe tannate.
This is similar to the so-called "rust converters".

Yup, that would be my understanding as well, Ariel.

Regards,
Kai

So the more coffee I drink the darker my insides get? :D

I'm not worried about that. There will be a wonderful wootz pattern on the insides :)