Wednesday, January 04, 2012

Sterling Clay Firing Results

It was an exciting moment to pull the brooch out of the carbon this morning. Overnight I had begun to worry about possible issues. I realized I should have provided more support to prevent slumping, but in my concern over carbon getting inside the window I forgot to address the second issue. Silly, really, when I'd just done the vermiculite open firing to provide such support. I placed it front side down on the stainless steel mesh, with only the tree in contact and the window slightly elevated above the surface. I woke up expecting the window frame to have moved under gravity until it contacted the steel.

So it was no surprise that the piece came out all wavy. In some ways it's almost nice, giving the piece a bit more dimension. However, I quickly went to work smoothing out those waves to give a more pleasing flow to the brooch. The sterling feels much stronger than a similar fine silver version would have. Even so, I was able to cushion the surface and carefully reshape the window.

The color of the fired sterling is lovely. Not bright white like with the fine silver, but a mellow low shine. When I polished up the back of the brooch, it seemed to take a bright shine more easily than fine silver, perhaps because it's harder. Now I'm torn on whether to polish the front or leave it matte.

This photo with the index card template I used to cut out the window shows the shrinkage, which I measured to be 18-19%. The fired weight of the brooch is 9.1 grams or about a third of an ounce.

Next, I need to check the hinge hole diameter, which looks pretty fine, and I may have to drill it larger. Then I'll cut, install and sharpen the double pin stem.