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84. Window Cap.—Figures 258 and 259 show the elevation and profile of a window cap in the form of an angular pediment. It is a combination of two horizontal mouldings having square return miters on their outer ends and two inclined or rake mouldings that miter upon each other at the center line, and with the horizontal mouldings at their lower ends. The triangular space beneath the rake mouldings contains a sunken panel.

This problem presents two new features; namely, a face miter at other than right angles, and a sunken panel. A profile is "drawn in" one of the rake mouldings in order to show the amount of "sink," and the method of joining the panel to the mouldings.

The details for a job of this nature are always furnished by the architect. The exact measurements must be taken at the building, where it is often found that a given set of windows will vary from ⅛ in. to ¼ in. in width. This variation is taken care of by lengthening or shortening the horizontal mouldings. This can be done by the cutter since it does not affect the miter cuts.

The elevation, Fig. 258, must be carefully drawn, care being taken to draw the rake mouldings at their proper angles. The miter lines must also exactly bisect the angle of the miter.

The profile, Fig. 259, is next drawn and the curved line divided into small spaces. Each point and vertex are then numbered. An extension line is now carried from the point of intersection of the miter line and the sunken panel, point A of Fig. 258, over into the profile as shown by point A of Fig. 259.

From each point in the profile, extension lines are carried over into the elevation, Fig. 258, until they intersect the first miter line. These extension lines are now carried parallel to the outline of the rake moulding until they intersect the second miter line, which is also the vertical center line of the entire elevation.

A line of stretchout, Fig. 260, is now drawn at right angles to the side of the rake moulding. Upon this line the exact spacing of the profile from points 1 to A inclusive should be laid down. Then by referring to the profile that is drawn in the right-hand rake moulding, it will be seen that distances 18–A, AB, and BC must be added to the line of stretchout beyond point 18. Extension lines should now be drawn at right angles to the sides of the rake moulding