Pertaining to blueprint design, what do feature control frames indicate?

Feature control frames are a crucial aspect of blueprint design, specifically pertaining to geometric tolerances. They provide clear, standardized information regarding how specific features on a part should be controlled during manufacturing and inspection. This includes defining the allowable variations in the size, shape, orientation, and location of those features.

These frames typically contain information such as the type of tolerance (e.g., position, profile, angularity) and the related datums, which serve as reference points for measurement. By using feature control frames, engineers ensure that parts not only fit together as intended but also function correctly within the overall assembly. This level of precision is essential for maintaining quality control in manufacturing processes.

In contrast, other options like surface quality standards, assembly instructions, and material specifications focus on different aspects of manufacturing and design but do not convey the specific geometric tolerances that feature control frames are designed to communicate.