Pre Processing :
A 3D model can be outputted on a 3D printer if the model is watertight, that means there are no holes and non-manifold edges do not exist. Preprocessing of 3D printing requires error correction, decimation of surfaces, cutting the model, and scaling and positioning on the (virtual) printer ground plane. A so prepared STL file will be send layer by layer in G-Code to the printing device. Independent from the real printing process, preprocessing extents the quality of ths data base.