The noded graph approach to stack analysis

The tolerance chart is a graphical method for representing the manufacturing dimensions of a workpiece or assembly, at all stages of its manufacture. The chart provides an inter-mediate control system of checks and balances to ensure that processing dimensions and tolerances will meet those specified on the print. Tolerance charts are generally used in studying the dimensional problems on individual parts. However, they have proved tedious in their application to assemblies. This paper presents a simple and systematic approach to the process of tolerance stack analysis. The "Noded graph" model is constructed, representing the given and the unknown dimensions. Links are then established, using the model, which help to formulate the stack path of interest into a linear equation. The equation is used to complete the tolerance stack analysis module. This will be explained using a variety of geometric dimensioning and tolerancing examples. In addition, it is simple and hence easy to practise and very logical.