ARTMOLIN@ACS.EKU.EDU on tue 26 jan 99
From: Ann Stecker
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I would be most grateful for any help with optimum firing schedules for
lowfire relief tiles.
I fired some test tiles for a relief mural and had everyone of them
crack. The tiles in the lowest part of the kiln not only cracked,
but were actually moved apart.(A large platter with even thickness, same
clay, fired perfectly on a shelf under the tiles) I'm
using Clayart Extra White low fire clay with sand. I bisqued to 05 and
glazed to 05. These were painted with commercial
underglazes and a Mayco commercial clear glaze. The tiles are 6" x 6"
and the relief is nearly 1 " in some areas with other
areas at 3/4"  1/2"  3/8". They were fired very slowly, but without a
controller. I was told by Clayart that it sounds like the
cooling was too rapid. So.......I purchased a Scutt KilnMaster
Controller. I asked Clayart and Scutt for recommendations for
a firing schedule for this project. They recommended different
schedules and I would like a recommendation for which
schedule is the best to use, or another schedule that would be better.
Do I need to fire the lowfire clay higher on the bisque
and why? Many thanks in advance for any and all help.
Annie Stecker
rekcets@open.org
Bisque firing cone 05 (could also be used for glaze) #1
segment 1 rate 50 p/h set point 175 hold 4 hr.
segment 2 rate 80 p/h set point 250 hold 0
segment 3 rate 250 p/h set point 1000 hold 0
segment 4 rate 150 p/h set point 1300 hold 0
segment 5 rate 180 p/h set point 1685 hold 0
segment 6 rate 80 p/h set point 1885 hold 20 min
segment 7 rate 150 p/h set point 1000 hold 0
Bisque firing cone 03 #2
segment 1 rate 175 p/h set point 200 hold 6 hours
segment 2 rate 200 p/h set point 210 hold 4 hours
segment 3 rate 200 p/h set point 2000 hold 0
segment 4 rate 200 p/h set point 1000 hold 30 min
segment 5 rate 200 p/h set point 500 hold 30 min
segment 6 rate 200 p/h set point 100 hold 0
Glaze firing cone 04 #3
segment 1 rate 200 p/h set point 210 hold 4 hours
segment 2 rate 300 p/h set point 1000 hold 30 min
segment 3 rate 200 p/h set point 1940 hold 0
segment 4 rate 200 p/h set point 1850 hold 1 hour
segment 5 rate 200 p/h set point 1000 hold 30 minutes
segment 6 rate 200 p/h set point 500 hold 1 hour
 
