The flatness tolerance zone is the volume between two parallel planes. Form, circularity, controls the form of a revolved surface in relation to its own perfect. Many part designs contain surfaces that need to be uniform. The flatness control c defines how much a surface on a real part may vary from the ideal flat plane. It is not dependent on any other datums or features. It controls the variations in flat surface, regardless of any datum feature. Flatness is a condition of a specified surface having all elements in one plane. It is a common symbol that references how flat a surface is regardless of any other datums or features. Perfect flatness is when all points of a surface lie in the same plane.
Engineering target market engineers engraving services export emachineshop cad to dxf, iges and step. Flatness, which regulates the deviation from the geometrically perfect plane, is measured using a dial gauge or a coordinate measuring machine. The flatness tolerance zone is two parallel planes 0. It controls how much a surface on a part may deviate from an ideal plane. It comes in useful if a feature is to be defined on a drawing that needs to be uniformly flat without tightening any other dimensions on the drawing. Flatness tolerance provides a tolerance zone of specified and defined by two parallel planes in where the specified surface must lie. Flatness is a form control, because it is used to control the form or shape of a feature. Sharing is caring flatness is a type of foam control. Using the best fit method of evaluating flatness, the deviations come out to. This page explains how to do this, as well as the advantages and disadvantages of using these instruments.