Living with a new kiln: the first ten firings
After six years with a second-hand kiln that had opinions about everything, I finally replaced it. The new one is a little bigger, has a proper digital controller, and arrived on a pallet that took three people and a lot of swearing to get through the garage door.
Firings one to three: learning the hot spots
Every kiln fires unevenly. I ran three loads of nothing but witness cones on every shelf, top to bottom, front to back. The top shelf runs almost half a cone hotter than the bottom. That is useful to know: glossy glazes go up top, satin and matte ones down below.
Firings four to seven: the schedule
My old kiln needed a long, slow ramp at the end to avoid pinholes. The new one heats so evenly that I was over-firing. I shortened the final hold from twenty minutes to ten and added a slow cool through the range where crystals form in my matte glazes. The mattes are now properly matte instead of slightly shiny.
Firings eight to ten: real work
Two full glaze loads of mugs and bowls with almost no losses: one mug with a crawled glaze (my fault, dusty bisque) and one bowl that stuck to the shelf because I glazed the foot too close. The usual mistakes, not the kiln's.
Write everything down. The firing log is the most valuable thing in the studio.