Abstract
Stereolithography is considered as a well‐known rapid prototyping technique that is widely used for injection molding and vacuum casting manufacturing regarding its higher dimensional accuracy and part strength. However, the extensive application of this process has been restricted due to the higher surface roughness and appearance of stair‐step phenomenon. In this article, the influences of process parameters and part orientation on the surface finish are investigated. For this purpose, parts are fabricated with different surface angle, hatch space, and postcuring time. The surface roughness of the parts are measured by contact and noncontact methods. In noncontact method, a digital microscope is used for obtaining the surface profile, and then surface roughness is calculated using MATLAB software. The results showed that the surface roughness was affected by the hatch space, whereas postcuring time had insignificant and negligible effect on the surface roughness. By increasing the surface angle, a sharp increase of surface roughness in up‐facing plane was observed, which was followed by a drop. Finally, with the help of analysis of variance, a mathematical model has been developed considering the process parameters and the responses. Moreover, maximum average estimation error of 14% was obtained between the experimental results of surface roughness values and the estimated ones