Copyright Goodheart-Willcox Co., Inc. 122 Section 2 Fundamentals of Shape Description Section View Lines and Principles The alphabet of lines contains two types of lines used for section views. These are section lines and cutting- plane lines. Section lines shade the area of material cut by the imaginary cutting plane. The cutting- plane line represents the edge view of the cutting plane. It is placed in the adjacent view to indicate the location of the cut. Section lines, also called crosshatch or hatching, can be created in a variety of patterns. Different patterns can be used to indicate the type of material used for the part, Figure 6‑2. In practice, however, section lines are often drawn with continuous lines about 1/8″ apart at a 45° angle. These 45° lines, like those shown in Figure 6‑3, indicate cast iron or malleable iron, but they can be used for general-purpose section lines. The sec- tion lines in a section view are not to be the only method designating the material for the object. The material specification should also be listed in the title block, in the materials block, or in a note on the drawing. While section lines are usually drawn at 45°, they can be drawn at any angle, but preferably not parallel or perpendicular to one of the major visible lines. The angle should be the same throughout the section view of a single part. A section view may serve as one of the regular views on the drawing, or it may appear as an additional view. As presented in Unit 2, cutting-plane lines are thick and may be drawn as a series of medium dashes or as a series of two short dashes and one long dash. An additional option is to simply show the cutting- plane line with thick “elbows.” Arrowheads are placed on each end of the cutting-plane line to in- dicate the viewing direction for the section view. Most often, capital letters are also placed near each arrowhead (A, B, C, etc.) to help identify the section views on the page with the corresponding cutting plane. The cutting-plane line can be omitted on a simple symmetrical object, but the standards recom- mend the cutting-plane line be drawn if the cutting plane is bent or offset, or if the section view that results from the cut is not symmetrical. Goodheart-Willcox Publisher Figure 6‑1. A section view allows a direct view of interior detail. Goodheart-Willcox Publisher Figure 6‑2. Section line patterns are standardized for different types of materials. Most of these are available for industry CAD systems, but general purpose section lining is still common. Magnesium, Aluminum Rubber, Plastic, Electrical Insulation Titanium, Refractory Metals Marble, Slate, Glass, Porcelain Cast Iron (general purpose) Steel Bronze, Brass, Copper Zinc, Lead, Babbitt, Alloys