The cracked base, although the break looks clean the piece also warped making gluing it nicely impossible.
Every profession has its ups and downs, but in ceramics, it's literal. The kiln's temperature rises to melt the glazes, hovers to allow the gases to escape, and slowly drops, allowing the chemicals to create vibrant colors. When throwing and centering, you turn the clay inside out by pushing it up to reveal the inner clay as you push it down. When coil building, you add height slowly, waiting for the clay to stiffen and strengthen before proceeding. Moving too fast will only bring the clay to a collapsing mess. I'm all too familiar with how my profession rises and falls.
So, after spending the week glazing full out on the tower project, watching the drawing come to life, and really getting the feel of what I created, it was with great expectation and trepidation that I opened the kiln on Sunday morning. The anticipation was, "Would the pieces be as beautiful after the firing as they were going in?" The worry was what if the pieces warped or cracked in the process. There were only two shelves; the first had three tower sections and a custom order, all of which fired beautifully. That success left me entirely unprepared for the disaster below. Taking the kiln shelf off and looking in, I saw that the base had split in half on the diagonal. After thirty years of doing this, I did not cry. I stoically rolled out another slab and threw another disc for the base for assembly the next day.
The four sides of sections 2 thru 4 fired beautifully and almost as important, straight.
On thinking it over, there are a few reasons why this may have happened. First, I used two clay bodies, one for throwing and the other for tilemaking. The former shrinks at 13% while the latter at 8%. I've created so many pieces using both and took such care in the drying process; this problem never entered my mind. There may have been a better choice than firing it on the bottom of the kiln. The heat is gentler in the center. So moving forward, I'll be recreating the piece in two sections eliminating the shrinkage issue and eradicating where to place it in the kiln. Unfortunately, this will leave the snake in the grass, not climbing the tower. Life is a series of peaks and valleys, and while this project is at a low point now, I know the rise will be spectacular.
Sections 5, 6, and 7 waiting their turn in the kiln. It’s taking me about a day to glaze each section so these sections will go in over the holiday weekend. Do you see the flying ladybugs?