the same drawing. This latter is usually done in a manner similar to ordinary drawings, by pencilling the. annual rings in wood, i.i a conventional manner, and indicating brick or stone work by straight lines ruled at an angle of 450 on the parts that are given in section. Some setters-out prefer to use coloured pencils to indicate these materials: red for brickwork, blue for stone, yellow for iron, etc. In any case the sectioning should be merely indicative, and not elaborate. The examples in this book, having necessarily to be considerably reduced, appear to err in this direction, consequent, upon the closing in of the lines in the reducing process. The method shown in Figs. 5 and f), page 183, of short straight lines around the outlines of the section, is a very good and clear method, and allows of writing upon the member, which is sometimes advisable.
No graining should appear upon elevations, as a stray line may be. mistaken for a working edge. If some special kind of wood is required in a certain place, such as a mahogany strip on the edge of a deal shelf, it is better either to write the description or to colour the portion red, or such other colour as will best indicate the material to be used. All chief measurements, such as clear size of openings, should be figured in with arrow head dimension lines, and, when a broken section is given, the true dimensions should always be figured across, as shown in Fig. 1, page 186. A broken width section has frequently to be given, as in the example of the width rod just quoted.
Rods are seldom used wider than it in., and more usually 9 in., except in cases where the work cannot possibly be draw upon such widths. Wide boards are very inconvenient to handle, occupy a great deal of bench space, and thus make the setting-out costly. It is generally quite possible to show all three dimensions of a job upon a narrow rod, as in the examples (Figs. 1 and 3, page 183, and Figs. 1, 2, 4, page 186). Fig. 1 gives the width of a door and the finishings, but not the width of the linings or thickness of the wall in which the doorway is made. This is shown
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