This section is from the book "Cyclopedia Of Architecture, Carpentry, And Building", by James C. et al. Also available from Amazon: Cyclopedia Of Architecture, Carpentry And Building.
B, thus obtaining the points of intersection 1x to 8x in elevation.
For the pattern, proceed as follows: At right angles to H F, draw the stretchout line J K, upon which place the stretchout of the profile A or A1, with all the points of intersection on the wash 1 2. At right angle to J K, and through the numbered points, draw lines as shown, which intersect by lines drawn at right angles to H F from similarly numbered intersections in the joint-line 1x 8x. Through the points thus obtained, trace the miter-cut M N O. Then will L M N O P be the pattern for the gable moulding.
In Fig. 298 are shown gable mouldings mitering upon a wash. The mouldings A A intersect at any desired angle the wash B. In this case, as in the preceding problem, an operation in projection must be gone through, before the pattern can be obtained. This is clearly shown in Fig. 299. Draw the section of the horizontal moulding B1 with the wash a b. From this section project lines, and draw the part elevation D C. Knowing the bevel the gable is to have, draw C B, in this case the top line of the moulding. Draw a section of the gable mould, as A, which divide into equal parts as shown from 1 to 8; and through the point of division draw lines parallel to B C, indefinitely, as shown. Take a tracing of the profile A, and place it in section as shown by A1. Divide A into the same number of spaces as A; and from the various divisions in A1 drop vertical lines intersecting the wash a b as shown, from which points draw horizontal lines intersecting lines drawn parallel to B C through similarly numbered points in A, at 1° to 8°. Trace a line through these intersections as shown, which represents the miter-line or line of joint in elevation.
For the pattern, draw any line as E F, at right angles to B C, upon which place the stretchout of the profile A, as shown by similar figures on the stretchout line E F. Through the numbered points of division and at right angles to E F, draw lines as shown, which intersect by lines drawn at right angles to B C from similarly numbered intersections on 1o 8o and on the vertical line B D. A line traced through points thus obtained, as shown by G H I J, will be the desired pattern.
In Fig. 200 is shown a front view of a turret on which four gables are to be placed, as shown by A A; also the roofs over same, as shown by B B. The problem consists in obtaining the developments of the gable mouldings on a square turret. In developing this pattern, the half-elevation only is required, as shown in Fig. 301, in which first draw the center line E F; then establish the half-width of the turret, as C D, and draw the rake B C. At right angles to the line B C, and in its proper position as shown, draw the profile A, which divide into equal spaces as shown by the figures 1 to 6, through which, parallel to B C, draw lines intersecting the center line F E as shown; and extend the lines below C, indefinitely.
Now take a tracing of the profile A. and place it in position as shown by A1, being careful to have it spaced in the same number of divisions, as shown from 1 to 6, through which, parallel to D C, erect lines intersecting similarly numbered lines drawn through the profile A, thus obtaining the intersections 1o to 6°, through which a line is traced, which represents the line of joint at the lower end between the two gables.
For the pattern, take a stretchout of A, and place it on the line J K drawn at right angles to B C, as shown by the figures 1 to 6 on J K.
At right angles to J K, and through these points of division, draw lines which intersect by lines drawn from similarly numbered intersections on F B and 1o 6o. Trace a line through the points thus obtained, as shown by Fo Bo Co 6o, which is the desired pattern, of which eight are required to complete the turret, four formed right and four left.
If the roof shown by B in Fig. 300 is desired to be added to the pattern in Fig. 301, then, at right angles to Fo 6°, draw the line Fo F1 equal to F H in the half-elevation, and draw a line from F1 to 6o in the pattern.
In Fig. 302 is shown front view of an angular pediment with horizontal returns at bottom A and top B. In this problem, as in others which will follow, a change of profile is necessary before the correct pattern for the returns can be developed. In other words, a new profile must be developed from the given or normal profile before the patterns for the required parts can be developed. It should be understood that all given profiles are always divided into equal spaces; therefore the modified profiles will contain unequal spaces, each one of which must be carried separately onto the stretchout line. Bearing this in mind, we shall proceed to obtain the modified or changed profiles and patterns for the horizontal returns at top and foot of a gable moulding, as at B and A in Fig. 302, the given profile to be placed in the gable moulding C. In Fig. 303, let C represent the gable moulding placed at its proper angle with the horizontal moulding G H. Assuming that 6x 6o is the proper angle, place the given profile A at right angles to the rake, as shown; and divide same into equal spaces as shown from 1 to 10, through which points, parallel to 6x 6o, draw lines towards the top and bottom of the raking moulding. Assuming that the length 6x 6o is correct, take a tracing of the profile A, and place it in a vertical position below at A' and above at A2, being careful to have the points 6 and 6 in the profiles directly in a vertical position below the points 6x and 6o as shown. Prom the various intersections in the profiles A' and A2 (which must contain the same number of spaces as the given profile A), erect vertical lines intersecting lines drawn through the profile A, a shown at the lower end from lx to 10x, and at the upper end from 1o to 10o. Trace a line through the points thus obtained. Then will 1x 10x be the modified profile for the lower horizontal return, and 1o 10o the modified profile for the upper horizontal return.