Etching nickel silver/copper damascus

[RN0601]

Hi, I'm a newbie here at the Knife Network Forums. I have a copper/nickel silver raindrop pattern damascus which I would like to achieve fairly polished surface finish and use patina to colour pieces. I would like to have copper being finished as dark as possible, contrast to nickel silver being light for a finish.

So far I have found an soda ash & Sulfer method here at the forums, but I am leaning toward using solution method involving chemicals that I am not familiar with. Chemicals that I am looking for are, copper carbonate, copper nitrate, copper sulfate, and ammonia.

My resources do not indicate on concentration of some of chemicals I have listed, or how hard or easy to obtain these chemicals are. If you have any idea on places I can find these chemicals (or product names) and/ or knows which concentration to use please share your knowledge/experience. I have really short deadline for the project which is undergoing in school and I would like to find out as much as possible to eliminate chances of limited amount of damascus I have from being wasted.

[Shakudo]

do you have nonferrous mokume or steel damacus? they are 2 different animals.for a patina on copper,boil an egg and use the yolk. also,you don't really want a polished surface with mokume.

[RN0601]

Thank you very much for a quick response Mr. Shakudo. By the way, I have a nonferrous NS/Copper mokume. I was wondering if egg yolk is supposed to be runny or completely cooked (to solid)? And do I need to rubbed it on, or to have enough egg yolk to submerge pieces intended to be colored? I have read few thread on finishing before etching (to #400 before etching then #600 after) but I will try several finishes and see if I can find a pattern I like to achieve. Again, Mr. Shakudo thank you so much for sharing your method. I'll let you know how pieces turn out on Friday night (that is my dead line, and just been informed day ago).

[DiamondG Knives]

Liver of sulpher will darken and antqie copper to a black color, dont know what it would do to nickle silver though.

[RN0601]

Thank you very much for sharing your method Mr. DiamondG Knives. Is liver of sulpher sold places like hardware store, or do I need to check with jewelry supply stores? I am not familiar with many applications, but I will definitely give a shot at liver of sulpher and egg yolk tomorrow. Sound like I'm going to have fun experimenting tomorrow in studio to find out what happens. Again, thank you very much for sharing your method Mr. DiamondG Knives.

[RN0601]

By the way I've tried egg yolk on piece of mokume yesterday. I was hoping for nickel silver to stay unaffected by egg yolk, but reaction seem to take effect on both alloy, and patterns are more noticeble than before testing on sample. I left a piece of mokume wrapped around covered in crumbled egg yolk and left it wrapped around with paper napkin for about 2 hours. I have no good reason other than not knowing how long egg yolk to take its effect, or not knowing how long it will take enough reaction to achieve finish I like to see and so I left it alone for sometime to see what it will do to mokume. Its facinating to me how egg yolk took effect on copper and nickel silver, but it did indeed looked interesting to find contrasts on crumbled egg yolk. Appearantly crumbled egg yolk that was in contact with surface of a mokume had slight green tint and turned much lighter than an egg yolk that did not contact mokume.

Well, theres lots more things I find it interesting but I'm going to clean this piece of mokume and try different effect. I'd like to try liver of sulpher and other finishes I heard may work. Thank again you two, I'll let you guys know if anything interesting happens.

[tonn]

Try this!

http://ganoksin.com/borisat/nenam/shakudo.htm

I used rokusho with mokume made of silver, shakudo, shibuichi & copper. I'm sure it works with You mokume too. At least - it's a different finish.
Good luck!

[KindOfBlue]

Thank you very much for the link Mr. Tonn. The site is full of useful information, I'm going to have to browse the site as soon as I get free time to read. I am planning to use copper sulphate/copper nitrate/salt mix tomorrow. Professor from chemistry department at my university was kind enough to help me with providing me with materials. I really can't wait to see the changes I'm expecting to see.

For last two days or so I have been playing etching mokume. I've notice copper seem to get eaten by acid faster than ns. I'd like to try to change rate and area being etched over time to see if I can make color or pattern contrast and/or transition on a test piece later on and see if that will reflect on color of mokume.

Well, I'm going to have to wrap it up tonight and finish up for Monday. Thank again Mr. Tonn.