Abstract: A stereolithography process for developing a prototype part in which inserts of a non-photopolymer material are included within the resulting part so as to develop a functioning prototype part. In order to allow the inserts to be placed within the developing prototype part, a series of STL files are defined for forming the prototype part in individual sections. A non-photopolymer insert is manually positioned on one section of the developing part each time a section is formed. In order to align one section to a subsequent section, alignment structures are developed by the STL files. In order to prevent the STL files from developing supporting structures in the cavities intended for the inserts, a supporting structure file is defined for a parent design, and then later combined with the STL files.