Elimination of building error in Rapid Manufacturing using iterative off-line building algorithm

Rapid Manufacturing (RM) is a recent technology which provides new opportunities in the manufacture of highly complex physical models, from a 3D CAD data. Unfortunately, the current CAD/CAM systems don´t provide any guidance to the user to predict or eliminate the building error. This paper presents an application study to analyze the dimensional building error of selected model. The study is started by reading the CAD file data, reorienting the model in definite different building orientation angles about its own axes, and then slicing the model with different values of layer thickness. The resulted errors at each layer thickness with different angles are then calculated and finally the suitable building orientation and suitable layer thickness that eliminate the error in Z-direction of the physical model is suggested. This study helps in building a complete physical model without wasting any material depending on its dimensions. It also provides guidance and valuable information to the RM users to get the best choice of process parameters without extra arbitrary trials before the actual building process.