Edge deformation

Edge deformation in rectangular porcelain

Unfortunately, the deformation of stacking edges is a recurring problem for all manufacturers of rectangular or square porcelain items (as the adjacent photo of a German premium brand shows). Just as a round plate - from a purely mathematical point of view - is never 100% round, straight edges of plates, platters and bowls can never be 100% straight.

Even the slightest changes in the atmosphere in the kiln could change the shrinkage of the goods to such an extent that stacked porcelain with low tolerance values can no longer be stacked perfectly. Raw material compositions with minimally different densities also lead to a loss of optical straightness in stackable, sensitive articles.

As long as the function of the porcelain is not really limited and the defect is only limited to the optical perception of the observer, we still count minor inaccuracies as part of the tolerance values which are identically recognised in the DIN standard 66072.