Rapid Prototyping is fast becoming one of the essential technologies that allow manufacturers to improve product quality and reduce both times to market and the cost of new lines. RP helps quickly fine tune the designs from concept to functional prototype that can cut product development schedule to weeks or months. A generative process planning system for parts produced by Fused Deposition Modeling is discussed. Process planning for RP involves optimal selection for orientation of model with a proper support structure and it requires an intelligent slicing methodology; direct or adaptive to minimize the built up time by keeping the geometry and cusp height errors in control. Pre and post slicing processes have been used to minimize the sliced data error. The CAPP model involves seven modules and it has been implemented in C language using a unique methodology. A set-up is being designed to fuse and extrude the FDM wire and it is being used in place of the spindle of a CNC milling machine. The proposed work can also be used for metal to be deposited and the whole set-up costs very less as compared to the commercial counterparts.