Recommendation? 300 year old damascus dilema

[NickHFSS]

Hello everyone , my friend gifted me piece of 300 year old dagger , which I turned into a push dagger.
for last few days I've been struggling with the finish.
I'm no damascus expert but the modern ones i've worked with worked with my proccess.
So first time I bring it to 2000 grit and medium buff , then I etched in Fecl for 1 minute , then sanded with 2000 grit , it came off obviously , the did 5 min , sand 2000 lightly it came off , etched 15min , came out beautiful pattern but again after light sand it came off.
thinking it was too polished I sanded up to 800 starting from 400 , reetched it now for 15 min , as you see in pictures it came out beautiful , I didnt even sand it this time , put window cleaner and water and pushed my finger to clean and as you see the black marks , the etching got lost , tried more with fingers nothing , tried sandning it came off and on one part tried to buff with the loose wheel with green compound and again all gone.
So I want a recommedation from people with more experience , what should I do next as I have little time until exhibition, maybe my fecl is not good ? as it was mixed like 3 years ago I think, maybe I can try something else , maybe just coffee? I'd experiment more but with leak of time if someone would give me directions it would be great.
Thanks

 

[Stacy E. Apelt - Bladesmith]

Nick - What was the source of the dagger - do you know where it came from? The pattern looks more like modern work.

Assuming it is 300 years old the pattern should be more of a hada (grain pattern) than a manipulated pattern. What we make today is called pattern welded steel. The simple way I explain it is that a hada is like the grain exposed in a board of solid wood. Modern damascus is more like what you get sanding plywood.

If the pattern is a true hada/damascus type your etching in FC isn't going to work.
Developing it using weak aids (like a Japanese sword) may work better. On a blade made from many folds of a bar of steel from a tartara or similar steel producing smelting setup, the pattern is very subtle. The steel is folded many times to get a more even distribution of the carbon from the bloom. The pattern seen is caused by surface oxides and silica residue of the fluxes used (often straw ash). Sometimes the pattern gets more distinct with age, but it is never a high-contrast pattern with high and ow spots and dark and light lines like a modern blade that is made from two or more different metal types.

 

[NickHFSS]

My friend is a swordsmith and armorer from Georgia but living in Netherlands for over 30 years now. He usually makes Caucasian daggers prices 10-40000euro , when he don’t make something he works restoring old swords for museums.
He told me it’s traditional Bulat steel which is not folded but made somewhat like boiling the two steels together. The blade is broken in half it’s typical Iranian dagger , I have the top part as well. He told me he etches using nitrous acid all the time 3% mostly , I don’t have this so I’ll give it a try.

 

[Stacy E. Apelt - Bladesmith]

OK, bulat/wootz. That is a high carbon crucible steel that forms bands and dendrites of carbide upon long heating and slow cooling.
To show the carbide as a bright inclusion, you are best to use an acid etch in nital, which is a weak nitric acid of 3% to 5%. Nital is used to show the crystal structures in metals.

Sometimes it is hard to get wootz to show much more than a surface effect because the pattern is rather subtle.
In these steels there are no layers of different metals, just carbides making the pattern. A mixture of nital (nitric acid and alcohol diluted to 3%-5%) is the standard etchant for bulat/wootz.

You only need a small amount of nitric acid to make a batch of nital. A high school or local university may be able to help you. 30ml nitric acid in a liter of distilled water is the ratio of acid to water. ALWAYS add the acid to the water when mixing.

If you can't get any nitral or nitric acid, you can try dilute HCl. It is sold as muriatic acid at hardware stores for cleaning concrete. Muriatic acid is 31% HCl. I have not tried it on wootz, but it should work similar to nitral. Try diluting it 1 part muriatic acid to 10 parts distilled water to get a 3% HCl solution and see how it works. 5-10 minutes should be long enough. Neutralize well. You may need to experiment with a slightly higher or lower concentrations.

FC will work, though.
Fc is basically a weak HCl solution. When I have worked with wootz blades when I had no nitric acid available, I used a 1:5 dilution of FC and water for about five minutes. I take out and neutralize then gently wash off the black crud. The pattern still shows faintly, but is not black and shiny as it looked with the crud. I repeat this many times until I get what I think is the best look.

Whichever method you use, It won't look like a multi-layer modern damascus. The final effect is more of a shimmery ghost of the pattern in shiny and dull surfaces.

 

[Stuart Davenport Knives]

Not to derail, but I am with you, Stacy. I finally ordered some FC, I diluted in distilled water, 1 part FC to 3 parts H2O, to try and highlight carbide banding. It looks awesome coming right out of the etch, but trying to keep that look is proving difficult. So I just etch for a few minutes, neutralize, and then polish with 1500 grit SiC. I repeat the etch/polish until I get at least something that looks decent and sort of highlights the carbide banding. I am finding that 3 cycles gets me sort of where I want it. I wish there was some way to "lock in" that look you get right as the blade is removed from the etch. I think trying to hilight carbide banding is harder to achieve than hilighting pattern welded steel.