Electrolytic Saltwater Etching of Copper

Results from electrolytic saltwater etching of copper



In my days at a semiconductor capital equipment company I made a lifelong friend. When we first met, she was a "process" engineer who etched the dielectric material on silicon wafers; then she etched conductive materials; then she was a product support engineer, et cetera.

A month ago I showed her the Art Jewelry magazine article on etching copper, nickel silver, brass and other materials in a salt water solution using a D cell battery. As an etcher, she was very interested. She'd never etched at home. Her current company (where they have a chemical that etches metal in only 20 seconds) is on holiday break, so this week she's free to come out and play.

Play we did - in our nerdy way. The local Radio Shack had only one single D cell battery holder, prompting an etching experiment. I purchased the single D holder, and also holders for a single C and two Cs.

We placed two sets of copper anodes and cathodes in almost identical etch setups at the same time. The main differences between the two was the number of C batteries and the resist designs on the copper.



Loooooook at the difference in the water color after a few minutes. The double C setup skipped the blue-green water phase and headed right to the orange water phase of the process. After five minutes the copper had significantly etched. After an hour, the copper was more than ready to be taken out. The single C battery tub etched much slower; after 2 hours the depth of the etch was still shallower than the 1 hour double C etch.

We etched both sides of the anode and purposely ignored recommendations to duct tape the edges - as you can see on Ben's piece at the far left.



Next time the process will be tweaked a little. Some rubber cement on the lead to the anode. Alligator clips instead of twisted and wrapped wires. Perhaps try a new type of metal. Duct tape on the edges. And, we'll measure the voltage and current from the single and double C setups and compare to the recommended single D setup.

By the way, we were shocked not to find a molecular orbital diagram of the process on wikipedia! ;-)

Calder Jewelry Exhibit at the Met

Friend and fellow jewelry artist, Pat Accorinti, forwarded me a link to a New York Times article about the Calder Jewelry exhibit at the Metropolitan Museum of Art in NYC. I especially enjoyed the slide show with closeups of ten Calder pieces.

Whale Shark!

Until last week, the longest I'd ever seen a whale shark is twelve seconds over eight years ago. I know this because that's exactly how long the video of my first whale shark encounter is.



After the last dive of the trip last week, the boat captain starting yelling down to us as we were heading back to the beach. We looked over the side and saw a whale shark right below the boat. The 20 foot long creature hung out for a while about 15 feet below the surface as we snorkeled above it. Awesome!

You can now access the whale shark video from 2000, and other trip video and slide shows, over on the right hand side of this blog.

Patina Expeirment Results

As promised...here are some photos of the brass bracelet and copper piece I was experimenting with in October.



I left the brass bracelet in the fuming container much longer than recommended, and the colored patina you saw in October washed off. Now that I've pushed that patina past it's time limit, I'll revisit it again someday and see how long to fume it so the blue greens stay.


The moist sorrel washed off leaving nice colors on the copper sample.




My favorite new copper patina is shown below on flat and hammered copper samples. The fuming recipe is comprised of sea salt, cream of tartar, vinegar, and ammonia.



You'll be able to read more about the cream of tartar patina in my "Accessible Patinas" article in the upcoming zine which Catherine Witherell and Deryn Mentock are publishing. They are busy compiling all the articles together now for a January release. More details to come.

Another fun result from the copper patina experiments is a mottled blue / green from sal ammoniac and tobacco. The results lead me to wonder what would happen if I ground up the tabacco even finer before this immersion process.



Here's a closeup look at the flat piece after rinsing

Lireille Gallery of Contemporary Jewelry and Art

Today I met with Yan Liu, co-owner of Lireille Gallery of Contemporary Jewelry and Art. If you stop by Lireille Gallery, you can now see seventeen of my necklaces, 30 pairs of earrings, and 20 rings. If you'd like a preview of my art work at Lireille Gallery, I created a catalog of the items in the gallery and posted it on my website on the gallery page.

One of the two new rings I created the night before is shown below. I took my cast sterling bottleneck ring design and applied texture and patina. The liver of sulfur left a very interesting purplish pink color in the grooves after the ring was cleaned in the ultrasonic. The flush set stones are 2mm and 2.5mm white topaz. (sorry for the picture quality - I should have left time for a photo session.) If you'd like a better look - it's in the Lireille Gallery.





I also took the same Bottleneck design in sterling silver, with the same textured finish, left it unpatinated and flush set 2mm peridot stones.

I like playing with the finishes and patinas. Which reminds me, I promised some more of my patina experiment pics in an earlier post which I'll get to soon.


Here's the rainbow over 880 seen on my way to Lireille Gallery.

Landmarks, Tanker and Tug Boats, and the Fog

Another beautiful fall day in San Francisco, with three city landmarks as seen from the end of Pier 8.

The tanker and tug boats passing below the bay bridge remind me of something from long ago - the colors are just right. I think the memory is from an old childrens book which has a tanker drawing covering two pages in the middle of the book.

At 3 pm, as the sun still shines brightly, the fog is starting to take back it's hold on the city.

the News

I headed over the the CNN website to find out about tonight's "Planet in Peril" show highlighting the 100 million to 10 death toll in the man vs shark war, and saw this headline: "World's corals reefs are vanishing, report says".

While I'm glad our largest eco system (oceans cover 2/3rds of our world's surface) is in the news, I wish the news was positive. Maybe the show tonight will discourage shark fin soup eaters once they know the devastation and cruelty that each bowl of soup has caused. I look forward to reading a news article about the lack of demand worldwide for shark fin soup.

Nice New Venue

Here's a look at my booth at The Virgin Artists Show & Sale. So many people have told us what a nice venue this is. Fourteen artists and a couple of tables for the refreshments all fit in here nicely. OK - time to get back there for the noon opening today.

New Earrings

I spent most of the day yesterday creating 22 new pairs of earrings with textures I'd taken on the Yucatan Peninsula. I especially like the fine silver pieces that look like coral and urchin shells. Here's a sample of the pieces:

Now it's time to pack up all the new earrings and head over to The 6th Annual Virgin Artists Show & Sale for today and tomorrow.

A Beach Full of Other People's Trash

On Monday night I cruised a beach on the Yucatan Peninsula looking for dead coral for making texture molds. In the picture below you'll see some of the pieces I found. And, *look* at all the sea glass I found. I was so excited I had to limit myself to picking up the less common colors.

Sure, I picked up a few dark brown and Heineken green, but look at all the light green and bluish green pieces! Other people's trash are now my treasures. The ideas for necklaces and rings and bracelets made with these pieces are swimming in my head. I wish I had more time before this weekend's show so I could make some of them. I'll let you know when I do and show you some pictures.