Page:Cassells' Carpentry and Joinery.djvu/52

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CARPENTRY AND JOINERY.

shown at a (Fig. 138) is best, and that at b second best, the object being to get the greatest number of pieces with the face nearly parallel to the medullary rays. The method shown at c makes less waste, but does not show up the grain so well; while d is the most economical when larger scantlings are required.

Fig. 138.—Converting Oak into Boards.

Fig. 139.—Square Scantlings.

Fig. 140.—Scantling from Centre.

Fig. 141.—Scantling from Side.

Fig. 142.—Scantling from Edge.

Fig. 143.—Planks.

Fig. 144.—Alteration of Form in Planks.

Fig. 145.—Warping of Planks.

Fig. 146.—Plank Cut to show Figure.

Fig. 147.—Oak Plank showing Figure.

Fig. 148.—Well Jointed Planks.

Fig. 149.—Badly Jointed Planks.

How the Cutting of Timber Affects its Use.

The method of cutting timber has a big effect upon its use. Fig. 139 shows square scantlings occupying three different positions in the same log; Figs. 140 to 142 show the alteration of form in each piece after sawing and seasoning. It will be noticed that Fig. 140 undergoes the least change. At Fig. 143 two planks are represented occupying adjacent positions in the same log. Fig. 144 indicates the change in shape of each after conversion and seasoning. The centre plank and those to the left in Fig. 145 indicate how boards cut from the log tend to shrink and warp if unrestrained. If the boards are cut as shown at k, there would be the least alteration in form. Timber should be cut as represented at Fig. 146 in order to show the figure formed by the annual rings. When it is required to obtain oak panels, etc., showing the beautiful markings of the medullary rays, the timber