Case Hardening Case hard timber cups and bows badly when ripped down its length on a rip or band saw. These twisted and miss-shaped timbers are difficult and wasteful to get straight for use in the joinery workshop.

Case Hardening is induced by poor seasoning. The kiln operator can test for case hardening (the inducing of stresses in the timber by poor seasoning) by taking a sample of the timber from the kiln, cutting a thin 'slice' and cutting the centre portion out of the sample on a band saw. What happen next to the sample will indicate if the timber is case hard. If the 'fingers' of the sample stay straight then no stresses are being induced. If the 'fingers' cup in or bow out then the stresses are being induced and the operator needs to recondition the timber in the kiln.

Honeycombing Poor attention to detail while kiln seasoning induces case-hardening in the timber and in the worst case this will lead to the cells in the timber shrinking and collapsing on themselves.