Restauration of antique oriental Damascus / Wootz blades

[mariusgmioc]

Restauration of antique oriental Damascus / Wootz blades

1. always wear protective vinyl gloves
2. clean the blade thoroughly with White Spirit
(3.) if the surface is rusty, remove all rust with Picreator’s Renaissance Metal De-Corroder, by either completely immersing the blade in the liquid or applying the liquid locally where needed
(4.) if the surface is badly pitted, polish the surface with sandpaper up to grit 2000-5000 (be careful that polishing is removing material from the blade, thus, it is an invasive procedure and should be applied with restraint; wootz is highly susceptible to pitting but slight pitting does not affect the end result too badly)
5. clean thoroughly the blade with White Spirit
6. etch the blade with Nital (solution of nitric acid 3-5% in alcohol) or with ferric chloride (20%)(best results have beeen obtained with Nital 3-4%).
6.1. protect the areas that do not need to be etched with polyethylene foil (cling film) and/or with Renaissance Wax
6.2. immerse the blade in the etchant solution, or apply the solution with cotton swabs, in quick moves in order to distribute the etchant evenly over the whole surface
6.3. the time for etchant to work should be very short, around 3-7 seconds (for Nital 5%) or may require more applications for longer times for Nital 3%, depending on the quality of the steel and the quality of the etchant (longer times at higher concentrations tend to cause a golden oxidation and can completely mask the watering patterns of the Wootz)
6.4. remove all the etchant by flushing it generously with running water (some suggest to neutralize the etchant by using water with baking soda but I did not try it)
6.5. dry thoroughly the blade with soft, absorbent tissue, and if necessary use a hot air blower (but make sure the air is not too hot since differential dilatation of the components of the weapon can cause major damage)
(6.6.) wipe very gently the blade with cotton swabs and Picreator’s Pre-Lim polishing paste (I use this to remove the golden oxidation that appears occasionally)
6.7. clean the blade thoroughly with White Spirit
(6.8.) repeat steps 6.2-6.7 two or three times
7. protect the whole blade with Picreator’s Renaissance Wax for long term conservation

Observations:
a. steps in brackets are optional, if necessary
b. The quality of the end result depends mainly on
• the quality of the Wootz
• the heat treatment of the blade
• the quality of the etchant.
c. I had situations where I got very different results, varying from a very high contrast, dark pattern similar to Kara Taban, to low contrast silvery-grey watering pattern over the length of the very same blade. I assume this was caused by the different heat treatment the blade was exposed to.

[Jens Nordlunde]

Thank you Marius, and Ariel for mentioning Nital.
I have never used Nital, but I will try it - using a 3-4% solution.
Marius, I think you are right, that the different results on the same blade must be due to different heating origianlly.

[mariusgmioc]

Originally Posted by Jens Nordlunde

Thank you Marius, and Ariel for mentioning Nital.
I have never used Nital, but I will try it - using a 3-4% solution.
Marius, I think you are right, that the different results on the same blade must be due to different heating origianlly.

Glad to be of help!

Not necessarily due to the ORIGINAL heat treatment but also to the subsequent heat treatments (for example a blade could get bent, and then was heated up locally to be straightened; or a blade could have been dropped into a fire... throughout its multi-centenary history).



And please let me know if you find a source of Nital in Europe as I normally get mine from the US.

[Jens Nordlunde]

Yes you are right, and your suggestion it likely to be more right than mine.

[Roland_M]

Originally Posted by Jens Nordlunde

Yes you are right, and your suggestion it likely to be more right than mine.

Hello Jens,

I have tried out a lot of etchants and in my honest opinion the original Zag (Iron + Sulfur but not Vitriol!) is still the best etchant. Difficult to work with, but fantastic results, if one do it right . Very good for pattern welded steel and wootz. Similar results like the original treatment.

The Dha/Dao from Sajen was recently etched with Zag for example.

But everybody has different experiences and preferences.


Roland

[mariusgmioc]

Originally Posted by Roland_M

Hello Jens,

I have tried out a lot of etchants and in my honest opinion the original Zag (Iron + Sulfur but not Vitriol!) is still the best etchant. Difficult to work with, but fantastic results, if one do it right . Very good for pattern welded steel and wootz. Similar results like the original treatment.

The Dha/Dao from Sajen was recently etched with Zag for example.

But everybody has different experiences and preferences.


Roland

Hello Roland,

Also using Nital I got results absolutely identical to (by no means discernable from) originally etched blades.

I got a magnificent black Kara Taban wootz kard that had a lighter area near the hilt so I had it polished (basically just cleaned the old etching with Pre-lim) and re-etched and got exactly the same I had before: a magnificent black Kara Taban pattern and much lighter area near the hilt where the etchant didn't appear to have the same effect (I assume because of different heat treatments to the blade, that led to different micro-cristalline structure of the steel).

Besides, Nital is very easy and reasonably safe to work with.


Maybe once I get home I will post some photos of my older results (but I know you also got excellent results with Zag)

PS: In the next future I will have to etch a few of my new aquisitions and I may make the effort to document the process with Photos.

[Roland_M]

Originally Posted by mariusgmioc

And please let me know if you find a source of Nital in Europe as I normally get mine from the US.

Hi Marious,

it's a commercial link, so I decided, to send you a private message.

If you use nitric, you have to use nitric with at least 65%, better 70% or more. This has nothing to do with the 2-4% you use for etching! This was a very important advise from an analytical chemist.


Roland