What causes lids to buckle?
Putting the screw bands on so tightly that air can hardly escape from the jars during processing. The buildup of pressure inside jars causes lids to buckle. Screw bands should be tightened firmly, by hand, So do not use a jar wrench to tighten screw bands. The best advice to is tighten the ring to finger tight. And remember when you take the jars out of the canner, the rings will be loose. DO NOT tighten them. Let them sit and cool. Then remove the rings, wash the jars and store the product without the rings.
