Etching wootz, opinion needed.

mariusgmioc · 3rd January 2020, 08:31 PM

Ferric chloride seems to be the next best alternative to Nital but
1. it is more difficult to work with as it tends to stain everything... including the sink;
2. the end result shows less contrast than with Nital;
3. it leaves the piece more prone to rust.

As with regards to the etchant store, they used to deliver to individuals until a couple of years ago. I particularly liked their 5% Nital that allowed me to dilute it down to 4% which in my oppinion delivered the best results.

Polishing thr surface to anything above 2000 grit (3000 in some cases) might be counterprodictive as the metal becomes so mirror-shiny that makes it difficult for the etchant to bite.

MichaelZWilliamson · 6th January 2020, 07:41 PM

That looks very much like someone heated a spot on the edge, either to straighten a deformation, or in attempt to re-harden a spot.

ALEX · 7th January 2020, 10:51 AM

Quote:

Originally Posted by MichaelZWilliamson

That looks very much like someone heated a spot on the edge, either to straighten a deformation, or in attempt to re-harden a spot.

This is quite possible. These white spots are result of overheating, either during or after forging. They become permanent part of wootz structure/pattern and once they're formed there is no way to 'remove' them by different etchants or develop better wootz pattern or contrast.

ariel · 7th January 2020, 05:13 PM

Highly likely.
European bladesmiths of the 19 century got plenty of wootz ingots and forged them into blades using European custom of heating the ingot to “ white”.

Surprisingly ( for them) the beautiful wootz ingots produced boring monosteel blades:-) Now we know why: at temperatures above ~850C dendritic structure just melts away and there is no way to restore it.

That raises another question: how did Persian or Indian masters managed to forge together 2 different samples of wootz to create scarf welding with only a thin line of amorphous steel as a scar?

3rd January 2020, 08:31 PM	#1
mariusgmioc Member Join Date: Sep 2014 Location: Austria Posts: 1,912	Ferric chloride seems to be the next best alternative to Nital but 1. it is more difficult to work with as it tends to stain everything... including the sink; 2. the end result shows less contrast than with Nital; 3. it leaves the piece more prone to rust. As with regards to the etchant store, they used to deliver to individuals until a couple of years ago. I particularly liked their 5% Nital that allowed me to dilute it down to 4% which in my oppinion delivered the best results. Polishing thr surface to anything above 2000 grit (3000 in some cases) might be counterprodictive as the metal becomes so mirror-shiny that makes it difficult for the etchant to bite.

6th January 2020, 07:41 PM	#2
MichaelZWilliamson Member Join Date: Nov 2018 Posts: 50	That looks very much like someone heated a spot on the edge, either to straighten a deformation, or in attempt to re-harden a spot.

7th January 2020, 05:13 PM	#4
ariel Member Join Date: Dec 2004 Location: Ann Arbor, MI Posts: 5,503	Highly likely. European bladesmiths of the 19 century got plenty of wootz ingots and forged them into blades using European custom of heating the ingot to “ white”. Surprisingly ( for them) the beautiful wootz ingots produced boring monosteel blades:-) Now we know why: at temperatures above ~850C dendritic structure just melts away and there is no way to restore it. That raises another question: how did Persian or Indian masters managed to forge together 2 different samples of wootz to create scarf welding with only a thin line of amorphous steel as a scar?