Hi! I have been making pots for about 7 years and in the past 4 have struggled with small s-cracks appearing on the bottom of about 75% of my pots. The s-cracks are usually around a half inch long, thin, and only on the underside of the pot - never go all the way through and therefore the pots are all fully functional, just annoyingly cracked. In the photo attached, you'll see 3 cracked pots, and 2 planters that did not crack. My theory is that something is amiss in the center of my pots that causes stress & cracking during drying - because typically, when I make planters that have the cen