#Zig zap line in construciton paper full#
The cross-hatching is the symbol for metals and may be used for a section drawing of any type of material.Ī section like the one shown in figure 3-37, which goes all the way through and divides the object into halves, is called a full section. The cross-hatching shown in figure 3-37 could be used on any drawing of parts made of only one material (like machine parts, for example, which are generally made of metal). On a third part, adjacent to two other parts, the section lining shall be drawn at an angle of 30 to 60 degrees.” On adjacent parts, the lines shall be drawn in opposite directions.
According to DoD-STD-100C, “section lining shall be composed of uniformly spaced lines at an angle of 45 degrees to the baseline of the section. The surface of the imaginary cut is crosshatched with lines called section lines. The lower view is a section, showing the pipe sleeve as it would look, viewed from one side, if it were cut exactly in half vertically. The arrowheads used on Navy drawings are usually solid, or filled in, and are between one eighth and one fourth of an inch long, with the length about three times the spread. The size of the arrowhead used on a drawing may vary with the size of the drawing, but all arrowheads on a single drawing should be the same size, except occasionally when space is very restricted. If these arrowheads are sloppily drawn and vary in size, the drawing will not look finished and professional. The arrowhead on a dimension or leader line is an important detail of a drawing. The other end, without an arrow, terminates at the point used as the center in drawing the arc. Occasionally, when the radius of an arc is to be indicated, there is an arrow at only the end of the line that touches the arc. Dimension LinesĪ dimension line, terminating at either end in a long, pointed arrowhead, is inserted between each pair of extension lines. When it is necessary for extension lines to cross each other, they should be broken (exceptions to this rule have been adopted since the development of CAD software). As far as practical, avoid drawing extension lines directly to the outline of an object. In unusual cases, extension lines may be drawn at other angles if their meaning is clear.