In this paper, a curved surface fitting method using a raster-scanning window is proposed to smooth the original organized point cloud data (PCD) and extract the original features in the presence of noise. The method allows PCD to be smoothed while keeping its own original features. Then, a Stereolithography (STL) generator is proposed to produce triangulated patches from smoothed PCD, and this helps to deal with a triangular representation of a 3D surface geometry. The process allows reconstructing 3D digital data of a real object described using STL format from original PCD in the presence of noise for reverse engineering. The effectiveness and usefulness of the proposed techniques are demonstrated through actual experiments to smooth PCD, reconstruct STL, generate cutter location source (CLS) data and perform machining of the object model described in the original PCD.