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Various Shapes of Mouldings

fig, draw, shop, mould and ogee

VARIOUS SHAPES OF MOULDINGS The style of mouldings arising in the cornice shop are chiefly Roman, and are obtained by using the arcs of a circle. In some cases, Greek mouldings are used, the outlines of which follow the curves of conic sections; but the majority of shapes are arcs of circles. In Figs. 268 to 272 inclusive, the student is given a few simple lessons on Roman mouldings, which should be carefully followed. As all pat tern-cutters are required to draw their full-size details in the shop from small-scale drawings furnished by the architect, it follows that they must understand how to draw the moulds with skill and ease; other wise freehand curves are made, which lack proportion and beauty. In Fig. 268, A shows the mould known as the cgma recta, known in the shop as the ogee, which is drawn as follows: Complete a square a b c d; draw the two diagonals a c and b d, intersecting each other at e. Through e, draw a horizontal line inter secting a d at / and b c at h. Then, with f and h as centers, draw re spectively the two quarter-circles a e and e c.

In Fig. 269, B shows the cyma reversa, known in the shop as the ogee, reversed. Complete a square a b c d, and draw the two diagonals b d and a c intersecting at e; through e, draw a vertical line intersecting a b at f and c d at h, which points are the respective centers for the arcs a e and a c.

C in Fig. 270 shows the cavetto, called the cove in the shop, which is drawn by completing a square a b c d. Draw the diagonal b d at 45°, which proves the square; and, using d as a center, draw the quarter-circle a c.

In Fig. 271, D represents the ovolo or echinus, known in the shop as the quarter round, which is constructed similarly to C in Fig. 270, with the exception that b in Fig. 271 is used to obtain the curve a c.

E in Fig. 272 is known as the torus, known in the shop as a bead mould. A given distance a b is bisected, thus obtaining c, which is the center with which to describe the semicircle a b.

All of these profiles should be drawn by the student to any de sired scale for practice. In preparing mouldings from sheet metal, it is sometimes required that enrichments are added in the ogee, cove, and bead. In that case the mould must be bent to;receive these en richments, which are usually obtained from dealers in stamped or pressed sheet-metal work. Thus, in Fig. 273, F represents a front view of a crown mould whose ogee is enriched. the section of the en richment being indicated by a b in the section, in which the dotted line d c shows the body of the sheet-metal moulding bent to receive the pressed work. In Fig 274, II represents part of a bed-mould in which egg-and-dart enrichments are placed. In this case the body of the mould is bent as shown by c d in the section, after which the dart is soldered or riveted in position. J in Fig. 275 represents part of a foot-mould on which an enriched bead is fastened. The body of the mould would be formed as indicated by c in the section, and the bead a b fastened to it. This same general method is employed, no matter what shape the pressed work has.