The generic capsule approach to tolerance stack analysis

The tolerance chart is a graphical method for representing the manufacturin g dimensions of a workpiece or assembly, at all stages of its manufacture. It is used to control tolerance stack up when the machining of a component involves inter-dependent tolerance chains. The build of the tolerance model is a complicated procedure. This paper aims at presenting a simple and sys tematic approach-the generic capsule approach, to the process of tolerance stack analysis. The model is constructed, representing the given and the un known dimensions. The proposed method uses, as the name implies, a generic capsule, which takes into account all the related aspects of the axis and s urface type of tolerance stacks. Links are then established using the model , which help 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, as we progress. In addition, it is generic and hence simple to p ractice.