Had a wonderful turn out for the first of the Metal etching classes. D Battery + Saltwater = Etching on the cheap.
I used the technique outlined in D Battery + Saltwater Cheap, Acid-Free Etching by Ron Pascho published in the Art Jewelry November 2008 issue. Basically you take a Single D Battery holder (I got them from Radio Shack for a dollar ea.) D Batteries. You can just attach these directly to the copper/brass pieces but I bought some stranded insulated copper wire and alligator clips to make extenders that could be cleaned or easily fixed if the copper ends got eaten through. I mixed up a super saturated solution of salt water. Pour out about 1 1/2 cups of water from a jug of distilled water into a pitcher for later. Mix in 2 cups of pickling salt into that gallon jug of distilled water. Put the lid on and shake the bejesus out of the jug let it rest for a few min and then shake again. If all the salt dissolves add more and shake again, if it dissolves add more salt. Keep adding salt and shaking the jug until it stops absorbing the salt.
Each of the pieces that is going to be etched mus first be cleaned. I used comet and a green scrubby to get all the oil off the copper and brass. You have to clean them until the water sheets off the metal. If it pulls away from the sides it still has oil on it, so keep scrubbing until you get a nice even sheet of water on the metal when you rinse it. Dry it off with paper towels and then don’t touch the front of the piece if at all possible. Leave the area around the hole bare, don’t cover it and don’t paint it. Put a piece of ducktape over the majority of the back leaving the hole at the top exposed. Paint the edges and your design on the front with a paint pen. You could also use a sharpie marker but I find that it wears off about half way through the etching process.
Fill the pickle jars with the salt water. I cut bamboo skewers in half to lay over the top of the jars. They help with securing the wires in the right areas of the jars. I put an ~ 2in piece of copper onto the exposed end of the cathode wire (black wire). Attach the anode wire (red wire) to the piece you want to etch. Place the pieces in the salt water, use the bamboo pieces to help hang them so that they are parallel with the side with the design facing the copper cathode. Put the D battery into the holder.
You should see bubbles. Lots and lots of bubbles. If it is going well it will look kind of like an alkaseltzer going. It will also start to turn really, really muddy orange. Let it bubble for an hour checking and wiping it off every 15 min. I wiped off both the anode and cathode pieces.
Once the piece is etched you can peel off the duck tape backing and scrub off the paint with a brillo pad.
I let the water in the jars sit over night. The precipitate all falls to the bottom. I pour out the water on the top put the orange gunk into a pan filled with paper towels and let the water evaporate off of them. I then collect the salt crystals and take them to the disposal day in Oak Ridge for recycling.
Here are links to pdf copies of the original article.
