The most commonly used input to a rapid prototyping (RP) system is the de facto stereolithography file (STL). Several problems plague these STL files owing to the very nature of STL files and the non-robustness of commercial CAD system model tessellators. The consequences of not correcting these errors are detrimental to the creation of the intended prototype. These are highlighted in the paper. In Part 1 of two papers, a description of all STL-files-related errors is given. The paper also proposes a generic solution to solve one of the major problems in the proper creation of a prototype, that is, the problem of missing facets. Part 2 deals with special cases of errors associated with the STL files. The performance evaluation of the proposed solution is also given.
