Soldering Copper: New Color-Match Copper Wire Solder
My recent experiments with copper paste solder left me disappointed, because of the visible seams. Sure, it’s easy enough to plate the silvery seam on soldered copper pieces, but only if you have a very strong, “green” pot of pickle. Just put the soldered copper piece(s) in it and toss in a piece of steel (a pinch of steel wool will work). That will cause the copper particles in the pickle to plate onto the visible seam, copper plating the white/silvery metal so that the seam doesn’t show.
But that’s not the best or most convenient solution for having invisible copper solder seams — a major drawback of this process is that it typically only plates the silvery seam with a thin layer, which tends to rub off easily during polishing — so I did some research and found that there were a few solders on the market that claimed to be a color match. I got some of the color-match copper wire solder from Rio Grande and I’m pleased to say it works!
I tested the copper solder wire using a simple propane torch. The solder melted and flowed very quickly. It did ignite a bit, just like the copper solder paste did, so be sure to work with good ventilation. The flame burns out quickly, but keep water and a fire extinguisher on hand, just in case (which you already have if you’re using a torch … right?).
This copper wire solder is 93 percent copper, but it’s 18-gauge and pretty hard. To cut it, I had to try too hard with my normal wire cutters and feared I’d ruin them, so I switched to memory wire cutters, which I never use anyway, so that worked out well! With it being hard to cut, it’s a bit hard to get the small amount that you’ll probably need, so the memory wire cutters from Xuron were very helpful for me.
Normally, you can hammer the ends of copper wire solder to flatten it a bit, making it easier to cut and easier to use, because flat pieces don’t fly or roll away like snips of round wire can. However, when I hammered the ends of this solder, it cracked. I tried using a piece of the cracked solder (or what amounted to two pieces, actually, since it had cracked) and it didn’t work. In my first attempt, the piece literally wouldn’t solder. That could’ve been a fluke caused by other factors so I tried again, and the second time it soldered but the copper color wasn’t “on top” anymore, and it no longer was a good color match.
Mark Nelson, Rio Grande Tech Support and jewelry guru, shared an important tip. If you use hydrogen peroxide pickle mix, note that it can turn this solder an unattractive gray color — which will defeat the whole purpose of using this great color-matching copper solder, leaving you, well, in a pickle. If you use regular commercial pickles like Rio Pickle or Sparex, or even vinegar, Mark says you should be fine. I use Sparex and had no issues. Sparex is a sodium bisulfate liquid that comes in a granulated form that is added to distilled water. If you are looking for a more biodegradable pickle rather than a chemical one, a few options to try include: citric acid (add a few tablespoons to a few cups of distilled water) and commercial-grade citric acid. What do pickles have to do with soldering, some of you may ask? A pickle is a liquid compound that is used to remove any baked-on flux and any oxidation from newly soldered jewelry pieces. A pickle solution effectively strips these oxides (also known as fire scale) from the surface of the metal.
To learn more about all kinds of solder and soldering, including beginner and advanced tips and techniques from industry experts like Lexi Erickson, Todd Reed, Helen Driggs, Tom & Kay Benham, and more, order or instantly download our new soldering publication, Everyone’s Guide to How to Solder Jewelry: Materials, Tools, and Tips. It’s loaded with information about solder, flux, torches and other tools and materials needed to solder jewelry, technique instruction to help you solder easily, cleanly, and neatly — plus 10 how-to soldering projects to show off your soldering skills. It’s a complete resource packed with information!