Internal Checking During Eucalypt Processing

Published Date

Date: 20 October 2010

Title 

Internal Checking During Eucalypt Processing

• Author 

• Philip Blakemore

Abstract

Collapse is a severe type of shrinkage that occurs to some extent in most species and timber types, but is particularly prevalent amongst certain species. The low to medium density Eucalypt species are particularly prone (Chafe et al. 1992). Collapse is “abnormal” in that it occurs in saturated timber above the Fibre Saturation Point (FSP) when the cell lumen is still saturated with liquid water, whereas normal shrinkage occurs below the FSP where moisture is lost from the cell walls, and the cellulose microfibrils in the walls essentially move closer together. It is collapse that causes much of the surface and internal checking problems when drying timber from many eucalypt species.

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