Fissures and resin pockets ~ defects in growth. Fissures, also known as shakes, are usually caused by separation of annual growth rings. Fissures and resin pockets must be limited in structural timber as they reduce resistance to shear and bending parallel to the grain.
Slope of grain ~ an irregularity in growth or where the log is not cut parallel to the grain. If excessive this will produce a weakness in shear. Measurement is by scoring a line along the grain of the timber surface and comparing this with the parallel sides of the section.
Insect damage ~ no active allowed. Wood-worm holes acceptable if only nominal. Wood wasp holes not
permitted.Sapstain ~ acceptable.
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