Explain the purpose of a machining tolerance chart.

The purpose of a machining tolerance chart is to specify allowable limits of variation in a machined piece's dimensions. Tolerances are critical in precision machining as they ensure that parts fit and function together correctly. They define the acceptable range for dimensions such as width, height, and depth, thereby guiding machinists on how tightly they must adhere to specified measurements.

By clearly laying out these limits, the chart helps in maintaining quality control during the manufacturing process. When parts are produced within the established tolerances, it guarantees that they will perform as intended when assembled with other components. Understanding and applying the information from a machining tolerance chart is essential for achieving the desired accuracy in machining operations, and it is a key aspect of ensuring product reliability and performance.