I think it was Benjamin Franklin who said, “Haste makes waste.” He was pretty smart.
I hate leaving empty space on my kiln shelf when I do a firing. It seems like such a waste; not at all efficient. As I was preparing the kiln for firing the other night, I decided I would “quickly” put something together to use the empty kiln shelf space. In my haste, I took a short cut. The piece should have been dammed, but I thought I could get away without it. Mistake! Let me show you what I mean.
Here is the space on the shelf.
Here is what I added to the shelf.
The piece I added is made with two pieces of gray glass (in different shades) on a clear glass base. The design element is made with 14 pieces of half inch squares that I made in a previous firing. I arranged the squares and capped it with a piece of clear glass. On either side I added a turquoise strip of glass that I cut 6mm wide and then placed on its edge. The pieces were all the same thickness and so I reasoned the amount of glass movement as the piece heated up would be minimal. I was wrong, and the turquoise strips got pretty wavy.
What I should have done was to add some fiber paper around the piece with some dams to keep everything contained and minimize the movement. I did think about it; should have listened to that voice in my head. Here is a picture of a piece I fired with dams.
As you can see in the photo below, the shelf side maintains straighter lines when firing glass that is placed on edge. Usually, I will do what is commonly referred to as a flip and fire. I sandblast the shelf side to remove any traces of the glass separator and then refire with the sandblasted side up just hot enough and long enough to get a glossy finish. The good news is that even without the dam, the shelf side of this looked pretty good. After some cold working to straighten the edges it will be ready to flip and fire. But then I will face the same dilemma… do I refire just this piece or wait until I have enough to fill the kiln?!