I’ve made an image out of dark annealed steel wire, soldered it together with silver solder and then soldered the image into a solid back sterling silver frame about 1.25" x 1.25" I put the piece in peracetic acid (peroxide and vinegar) to clean off the flux but it didn’t clean the oxidation on the silver so I sanded the piece and it’s okay but I’m wondering if there is a better way to clean a piece that is steel and silver combined.
I’ve found when silver soldering with steel that I have to pickle the piece to clean the oxides from silver, I use a warm citric acid and water solution, and then I use a warm super pickle to remove the copper plating. I use a 50/50 mix of 3% hydrogen peroxide from the pharmacy and clean citric acid pickle.
It’s important not to leave your piece in the super pickle too long or it will re-plate. It may also leave a dull grey finish on your entire piece. This dull finish can be removed with 3M radial discs, fine emory paper or steel wool, but it’s easier to keep an eye on things and take the piece out of the solution as soon as the copper disappears.
That’s great news! Thank you… Sounds like the perfect solution(no pun intended). Where do I get the citric acid… just powdered vitamin C?
I buy mine in bulk online, food grade powdered citric acid. It’s available on Amazon, eBay, etc. You may find it in the grocery if they carry canning supplies or if you have a local feed and grain store they may have it too.
I know this solution works using Sparex as well. What do you use as a pickle? We have to be very careful when combining chemicals on the studio.
Hi Pam… thanks for the information. I use Rio pickle which I believe is the same thing… sodium bisulfate that releases sulfuric acid when mixed with water.
How do you like the citric acid pickle? It sounds like you are using it as a substitute for sparex, is that right? Is that because it is less toxic? How fast is it?
It sounds like you are saying I can just put my piece in regular pickle isolated from other pieces and then remove the copper plating with super pickle… ie do not be afraid of big bad copper plating??? That’s a relief, if that is what you are saying!
I apologize for the delay in responding. I’ve used citric acid pickle for years. It’s slower than Sparex, but I prefer to use it in my home studio. You definitely have to use it warm.
It’s an extra step to have to remove copper plating, but that’s one of the trade offs for mixing these metals. If your silver has copper oxides you’ll have to pop it in the pickle to remove them. Be sure not to leave your piece in the super pickle too long or it will begin to etch and may pit your solder seams. Once warm, it works pretty quickly.