I have been making vases off and on for the last year and the base of them always baffled me. The tops would keep a similar ruffled shape. But on some, the ruffles came straight from the base.
And on others, it pulled in tightly before it began the ruffles.
So I decided to figure out why the difference. I had 2 theories. The first was based on color as I tended to see the former on the lighter colors like amber and light blue. The second theory was based on size as it seemed like the bigger circles are the ones that pulled in. Of course, I wasn’t sure on either of these since I had never really paid attention to these details.
To start the experiment, I made a 10″ circle of deep blue. This would test if the color mattered as it was a darker color. For this one, I ended up not getting a pull in at the bottom, so it blew the theory about the color being what made the difference!
My next test was immediately after the first test so I could make sure everything stayed the same with kilns and firing schedules (meaning temperature and time). I made a second vase in red, but this time, I made the circle 11.25″ (the largest I can make in my kiln). With all the other variables being the same, I ended up with the nice pull in you see above on the red vase. Retrospectively looking at many of my previous vases, it seems to follow that if you like the pull in at the bottom, then you need to make the circle larger and let gravity be your friend!