Selection of Process Parameters for the Precision of Screw-Shaped Objects on Reprap 3-D Printers

摘要

The recent development of the Reprap project, hence the 3D RepRap printers, has made 3D polymer-based fused deposition modelling (FDM) technology prevalent among office and home users. Although fused deposition has many advantages in terms of speed and the ability to deposit molten polymer material with feasible strength and other material properties, shape imprecision is one of the main problems involved with freeform fabrication with FDM method. Especially, when an object to be printed is unique in a shape of overhang and with options of various print orientations, obtaining shape precision requires various process parameters to be fulfilled. In this study, a model similar to the screw commonly seen in a mould injection machine is employed as the printed object. Process parameters include print orientation and support structures are considered to assess their effects on the shape of the object. The process parameters are demonstrated and the effects are compared and discussed. Conclusions are made including special design of support structure be considered to comply with model geometry.