What type of lines should be used for hidden features on a stock drawing?

In technical drawing, hidden features are represented using dotted or broken lines. This type of line is specifically designed to indicate details that are not visible from the current viewpoint, allowing the viewer to understand the complete form of the object. Dotted or broken lines create a clear distinction from other elements on the drawing, ensuring that hidden elements are easily identifiable.

Using a distinctive line style for hidden features is essential because it communicates critical information without cluttering the drawing with unnecessary details. Solid lines signify visible edges and outlines, while dashed lines can sometimes denote alternate positions or representations in certain contexts, such as section views or center lines. Double lines are typically used for representing the thickness of walls or other features in architectural drawings, making them inappropriate for indicating hidden features. Thus, dotted or broken lines are the standard practice for showcasing features that are obscured from view in stock drawings.