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Blackening pattern welded stainless

May 19, 2009

Hi , I'm a hobbyist blacksmith and I have just started making pattern-welded stainless steel , my problem is I can't figure out how to make the stainless get a black/silver alternating pattern, I'm using 304 and 316 alloys , polished to a mirror finish and etched in hydrochloric acid, the 304 will etch very deep and be covered in a blackish film but when I take it out and rinse it off, it goes back to dull grey/silver. I don't know if I need to do a black oxide on the whole piece and buff the high spots off, or if there are formulas for this?
I'm hoping someone with more chemistry experience can help me .
thank you


(for those unfamiliar with pattern welding: en.wikipedia.org/wiki/Pattern_welding)

Andrei Hand
hobbyist blacksmith - Amherst, New York

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Try to buy book by Jim Hrisoulas:The Pattern Welded Blade-Artistry in Iron,but even in that contemporary book,you can't find anything on SS blades.There are some patinas for SS and you can try them (thiosulphate based,chromate based+ electrolytic colouring methods).Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia
May 25, 2009

You can try masking off the areas you want to remain stainless then dip in a cold black oxide treatment solution.

Cliff Kusch
electropolishing shop - North Vancouver, British Columbia, Canada
September 18, 2009