Types of cut

The two main types of cut - plain sawn and quarter sawn - refer to the angle between the timber face and the growth rings. This is best observed from the end of the timber, as in Figure 4.9. If the cut is such that the growth rings meet the surface at less than 45° then the timber is plain sawn. Timber with this type of cut tends to have a more decorative appearance but a greater tendency to distort by cupping. Timber cut with the growth rings meeting the surface at not less than 45° is quarter sawn. Such timber is harder wearing, weather-resistant and less likely to flake. If a log is cut through and through, which is most economical, then a mixture of plain and quarter-sawn timber is produced. Quarter

Quarter cut with boxed heart Fig. 4.9 Conversion of timber

sawing is more expensive as the log requires resetting for each cut and more waste is produced; however, the larger sections will be more dimensionally stable. The centre of the tree, the pith, is frequently soft and may be weakened by splits or shakes. In this case the centre is removed as a boxed heart.

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