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Originally Posted on: May/28/2005 21:53
Saggar Fire Samples
Last quarter I took a saggar fire class at Red Kiln taught by Ken Marvel and Chuck Parsons. Great class. Wanted to share some of the great effects from the fire. I brought pictures:
1. Copper scrub pad (Chore Boy brand) opened up creates a weave of thin copper wire. Copper wire creates deep brown or black lines on the pot.
2. Salted pistachio nut shells (half) glued with Elmers glue to the pot did two things. First, the salt created a flash of red and second the shell protected the pot from smoke creating a white oval with crisp edges.
Chore Boy scrub pad and sawdust in a small sagar made this one black. The white area was at the top where the sawdust burned off revealing the weave of the copper wire
Finally, this close up is a large box was fired in a pit fire last year. No color appeared. So I re-bisqued. It emerged with blue flecks from some cobalt in the pit fire. I then created a sagar specifically sized for the box and fired with sawdust, salted coffee (boil used coffee grounds in salt water then dry), seaweed and copper wire. I have no idea why it came out with vibrant turquoise, but no complaints.
Dawn - post more about that torquoise. The effect is likely from the cobalt left over on your pot from the pit fire. How did you apply it to your pot in the first place? Also, did you have any problems firing that piece 4 times (bisque, pit, bisque, sagar)?
Unfortunately, there was no scientific application of the cobalt in the pit fire. As we loaded the pit cobalt and chrome was randomly scattered. Dumb.
Now, I would either spray the piece with oxide a week before fire to let it dry - or - soak cotton rags in the oxide, let them dry and wrap them around the piece. Same treatment for pit or sagar.
I never want full control over a sagar (or pit) fire. The random variation is the whole point. But I do want to be able to encourage certain colors and patterns as well as note what was done in order to try to repeat it. "Then we tossed some cobalt in" just doesn't cut it.
Forgot to answer your second question. My pot did not seem to suffer any ill effects from being fired repeatedly. I notice my sagars wear out faster from the repeated fires than my pots do.
I have a theory that the thick sagars are actually cracking sooner than thin walled pots. I have created some thin walled sagars to test my theory and will post the results.