Selected Bibliography Architectural Graphics | Page 28

DRAWING CIRCULAR ELEMENTS • To avoid drawing am ismatched t angent to a circle or curved line segment, always draw the curvilinear element first. • Then draw the tangent from the circle or arc. • Care should be taken to matchthe pen or pencil line weights of circles and arcs to the rest of the drawing. • T draw an arc of a given radius tangent to two given o straight line segments, first drawlines parallel t othe given lines at a distance equal to the desired radius of the arc. • The intersectionof these lines establishes the center of the desired arc. • To draw two circles that are t angent to eachother, first draw a linefrom the center of one to the desired tangential point on its circumference. • The center of the second circle must liealong the extensionof this line. 22 I ARCHITECTURAl GRAPHICS