Sorry for the lack of recent updates, this firing blog has been a bit horrible to get correct. Here we go for another day of fusing.
So as you remember, we have already take the kiln through it's initial paces and we are now waiting for it to get to temperature. Not to worry, this does not take long at all. Within 8 minutes, my particular kiln is already at 1000 degrees.
At one thousand degrees, the pieces of glass look just like they did when you put them in, there is no deformation of the edges, no softening of hard lines. Just glass.
The next milestone is 1500 degrees, now some glass experts fire directly to 1500 and stop for a while. Having an infinity switch I have no such option. So I tend to let my kiln heat up a little more. This can be a touchy time in many ways, since Dichroic coating has a tendency to burn out or scum up at higher temperatures.
So as you can see in this shot, at 1500 degress, I have a lot of round edges, and peices have come together at almost all points. At this point in the process I turn the kiln off, and close the lid for about a minute.
What a difference a minute makes, as you can see in this photo the pieces themselves are glowing now, The elements of the kiln are glowing as well, but most of the infared radiation is coming from the pieces themselves. Thy also have rounded out a lot mor ethan in the previous picture (this is how I get my pieces to look more like lapidary work than glass) At this point I vent my kiln.
This means I literally throw off the lid and let the temperature quickly cool. This is an iffy process and is only observed on a first firing. On a second firing I always anneal through the entire cooling process giving the glass time to become stronger.
As this picture illustrates, there is still a lot of infrared coming of the pieces, but that they have definitely lost a bit of their glow. This is about 1000 degrees and I will put the lid back on and wait.