Let E C G1 F G C1 of Fig. 476 be the plan of the article, and I N O K the elevation. By inspection of the plan it will be seen that each half of it consists of two arcs, one being struck from D or D1 as center, and the other from C or C1 as center, the junction between the two arcs being at G and G1, respectively. From C draw C F, and likewise draw C G. Upon the point D1 erect the perpendicular D1 C1.
To obtain the radii of the pattern construct a diagram, shown in Fig. 477, which is in reality a section upon the line C G of the plan. Draw X P in Fig. 477, in length equal to the straight bight of the article.
Fig. 478 - Pattern.
Fig. 476. - Plan and Elevation.
Fig. 177. - Diagram of Radii.
The Pattern of a Heart-Shaped Flariny Tray.
Lay off the perpendiculars X U and P S indefinitely. Upon P S, from P, set off P R, equal to D1 C1 of the plan, and on X U, from X, set off X W, equal to D' c of the plan. In like manner make P S equal to C G of the plan, and X U equal to C g of the plan. Connect U S and W R. Produce P X indefinitely in the direction of Z. Also produce R W until it meets P X in the point Y. and in like manner produce S U until 'it meets P Z in the point Z. Then Z U and Z S are the radii for that portion of the article contained between G and F of the plan, and Y W and Y R are the radii of that portion shown from G to E of the plan.
To lay out the pattern after the radii are established, draw any straight line, as Z1 G2 in Fig. 478, in length equal to Z S of the diagram. Prom Z1 as center, with Z S as radius, describe the arc G2 F1, in length equal to G F of the plan. In like manner, with radius Z U. from the same center, describe the are g1 f1, in length equal to gf of the elevation. Drawf' F1. Set off from G2 upon the line G2 Z1, the distance R Y of Fig. 477, as shown at Y1, and from Y1 as center, with the radius R Y. describe the arc G2E1, which in length make equal to G E of the plan. In like manner, from the same center, with radius Y W, describe the arc g1e1. equal to the arc g e of the plan. Draw e1 E1, thus completing the required pattern.