What are reference dimensions typically enclosed in on a drawing?

Reference dimensions are typically enclosed in parentheses on a drawing. This notation is used to indicate dimensions that are not used for manufacturing but provide additional information about the design. The use of parentheses helps to differentiate reference dimensions from critical dimensions that are essential for the machining or production process.

Reference dimensions offer helpful context, such as indicating the size of features in relation to other parts of the assembly without being a controlling factor. This is important in engineering and design, as it ensures that clear distinctions are made between dimensions that must be adhered to and those that serve only as informative references.

In engineering drawings, clarity and precision are key, and the use of parentheses for reference dimensions plays a significant role in maintaining that clarity. Other symbols, such as brackets or curly braces, have different meanings or applications in technical drawings, further emphasizing the importance of using the correct notation for each type of dimension.