Document Type : Original Article


Assistant Professor, Faculty of Engineering, Helwan University, Cairo, Egypt.


Recently, developing Additive Manufacturing (AM) technologies have been
increased, because its advantages toward the rapid manufacturing of physical model
from the CAD system. In the AM area, the designer specifies the desired surface
quality on the working drawing to be considered during the building operation. The
produced surface depends on the building parameters. The aim of this work is to
develop new empirical models for predicting the building orientation that satisfy
required surface roughness based on FDM m/c. In this study, a new 3D CAD
specimen was proposed to decrease the number of experiments, measuring errors
and building cost. The specimen contains the surface orientation from 0o to 90o with
step 10o that was built three times at three different layer thickness (0.1, 0.3, and
0.4mm). The order of the model was determined by the test of all orientations accept
at 30o and 60o that was used for model verification. Results show the three prediction
models at certain three values of layer thicknesses. The prediction of building
orientation has several benefits as follows; it is very useful information for the
designer before exporting STL file, the AM users can choose the process parameters
without extra trails, increase the opportunity of technology to shear in Rapid
Manufacturing (RM), Rapid Tooling (RT), and in medical applications.