I’d like to hear about everyone’s experience with pickling. Do you make your own pickling solution or buy something? What do you use for pickling brass and what do you use for pickling steel? I attempted to pickle my steel mounts with Sparex #2. Now I’m reading online that steel “contaminates” the pickle. Does that mean the pickle is now useless for my brass mounts? I’d love to hear everyone’s expertise on the subject of pickling. I’m using silver solder with brass and silver solder with steel, that I’m brazing with map gas.
Kim Flora Cincinnati Art Museum
We use Sparex # 2. For steel we TIG weld. I think that contamination is more a problem in jewelry making. If the brass comes out of the pickle with a patina does it matter?
Cleveland Museum of Art
11150 E. Blvd.
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Kim, It doesn't necessarily contaminate except that steel in the pickle will copper-plate any brass that's in there at the same time. I am not aware that copper-plating a brass mount hurts anything however. To my knowledge steel doesn't need to be pickled. If you're using flux with steel fabrication, say for brazing, the flux does need to be removed. As I understand it the flux helps create an electric-charge that will eat away at the join if it's not removed but I may need correcting. If you're not fluxing steel just use a wire brush and water to remove oxides before priming and painting. To remove flux after brazing steel (with silver solder or bronze brazing rod) quench the work while it's still hot and the flux will dissolve/come off in the water. I have a big 5-gallon bucket for quenching. I don't put anything other than brass in the pickle-pot. Stainless steel is OK in the pickle however. It will not copper-plate anything, even if that's an issue. You'll probably get a ton of responses. Good luck! TGIF! Bruce Raper
Hi Kim. My background is in jewelry-making and metalsmithing. There have been some times when I’ve had to combine brass and steel with silver solder. The contamination was explained to me as “contact plating”. This only seemed problematic if you had metals in the pickling solution that you didn’t want accidentally copper-plated, like silver. Once the steel is removed, the “plating” stops and the pickle is fresh as a daisy again. That’s why you usually see copper tongs used in retrieving precious metals from those crock pots in jewelry class. I hope this helps.
Suzi McG 8/19/11
My background is also in jewelry/metalsmithing and what Frances and Bruce say are correct. I'm probably a little more cautious about mixing metals in my pickling solution. Probably because I'm often making jewelry & art at the same time as mountmaking. I use Sparex for the brass and I also mix it with distilled water. We have very hard water here and I've just found that it seems to be a more efficient solution with distilled water and I do get less plating on the brass. Not that it really matters if you're going to paint the mounts anyway.
I do change out my pickling solution fairly often (depending on how busy I am in the studio) and I do neutralize and clean the old pickle & pot very thoroughly before dumping it.
When I bronze weld steel I don't pickle it - just quenching and a good brushing or bead blast is all it needs to be clean enough for painting.