Wednesday, February 2, 2011

Copper Clay

Since Art Clay makes a copper clay that can be torch fired or fired on an open shelf for 30 minutes it is now possible to do a class in copper in one day.

An earlier post featured a work by Phil that had cracked and broken during firing. Phil was in my first ever copper clay class. We all struggled with the clay that day. It seemed very stiff, hard to condition and cracked easily. Art clay copper has a shelf life of six months and we were wondering if the clay was old (even though I had just ordered it a few weeks earlier.) Contrary to my first experience with kiln firing this clay, this batch stuck to the shelf and had to be pried off. Most of the fire scale dropped right off when dropped into water. The rest came off in the "pickle" solution. (What I used wasn't real pickle solution but something I bought from Cool Tools that is safer.)

Well, that experience rather bothered me. I want my students to have the best possible experience and come away from the class with something they are happy with. I think they were basically happy with the class but not without a struggle and a real learning experience.

I had two other packs of copper clay that were ordered from a different vendor. So last Thursday, Ginnie (who was also in that class) and I tried again. This batch did seem different. It wasn't quite as stiff. It did still require quite a bit of water to make it pliable (like the silver clay.) Quite a bit more.... about three times as much. Since the jury is still out on copper clay I stuck to making very basic simple pieces. (Got to get over this!)

Another thing we did this time was make our pieces a couple of cards thicker than we did last time. Silver clay is good at two cards thick but the copper seems best at four or more. (Three cards is do-able, but four is better.) Even with the added thickness, the pieces are very light when fired. If less cards are used, there isn't enough heft to hang nicely on a chain. Less cards are good though for earrings.

The final thing I did differently was to put some firing paper (used for glass..... just can't think of what it's called) on the kiln shelf. This time the pieces slid right off the shelf.

The pickle solution had been left in the pot and of course was cold. But since it was the end of the day and we wanted to get home, we dropped in our pieces. They basked in there for four days and were very clean.

Ginnie and I were both happier with the results this time. The copper clay is never going to rival the ease of working with silver. The surface of the copper clay isn't as nice either (maybe I'm missing something) but time will tell.

Thought I'd share some of the copper earrings I made that day. People do seem to like the copper jewelry. It's something different.


Zoe Nelson said...

I've found the copper clays to be a whole different animal than silver, too. I like silver clay so much better. I wish the price would come down!

Alice Walkowski said...

Me too !!!!!!!

Anonymous said...

I'm still making very simple, basic pieces from the "base metal" clays too.

I was initially interested in those clays in large part because I'd really like to make designs that are both bigger and more complex. Until I master firing them, however, I'm just not willing to sink a lot of my precious time into a piece that may or may not sinter properly.