Monday, July 12, 2010

Two years later

Bronze clay was introduced two years ago at the PMC Conference. We were all given 30 grams of bronze clay to try. I also bought a 100 gram package. Well, two years later I'm finally giving it a try.

The 30 gram pack was hard as a rock, but I was able to work with the 100 gram pack. Since the outcome is not always predictable, I decided to just keep it simple until I saw how things were going to work. (Actually the unpredictability of the clay is the reason I waited this long. I was waiting until other people worked out all the kinks.)

Bronze (and the copper) is considerably cheaper than the silver clay. But, I found both of them harder to work with. Both the copper and bronze have an elasticity that the silver doesn't have, so joints may crack open during firing. The bronze clay is stiffer and gets stiffer the longer it is worked. It has to be cooled to make it more flexible. Since my clay was two years old I wasn't sure exactly how "stiff" it should be. (I've ordered another package to try, then I'll know for sure.)

The clay is also very "dirty" to work with. It stains the hands and creates a very dark dust. Basically I don't like working with it. (I wasn't too crazy about working with the copper clay either.) Come to think of it, my first exposure to silver clay was less than rewarding too. Who knows, maybe I will like working with it eventually.

For firing, bronze clay has to be surrounded by activated charcoal in a steel container. The container is set up on kiln posts. The pieces have an inch of charcoal under and over them. And, there must be one half inch between the pieces. For thin pieces the kiln has to be ramped up slowly, 500 degrees per hour. Once it reaches 1550 degrees, the temperature is held for two hours. This whole process takes about five hours. Finally the pieces are left to cool in the charcoal container over night.

Tomorrow will tell. I'm looking forward to opening the container (fishing out the pieces) and seeing how they turned out. Hopefully everything is good. Hopefully, taking two years to try the clay pays off. I'll let you know.


Meg said...

Good luck with the bronze !!!

Zoe Nelson said...

I haven't worked with Bronze yet, but had to try copper 3 times before I was successful. I was hoping that I could wind up with some less expensive pieces for sale because the material costs less, but when pricing the copper pieces I realized that it takes just as long to make a copper piece as it does a silver one (maybe longer because of the long firing) so the end result isn't that much cheaper. The jury is still out on whether I'll do more copper or not. I'm with you - I don't like the mess.

Alice Walkowski said...

Thanks Meg. Zoe I agree with you. I've tried the copper a couple of times. Once successfully and once, not so successful. It seems to take me longer to work with the copper (and the bronze) so I think the price difference is eaten up in work time. I'm going to try the ACS copper soon (won't wait two years.) I'll let you know how that one turns out.