Major drawback associated with parts produced by fused deposition modeling (FDM), an extrusion-based additive manufacturing (AM) technologies is poor quality, such as shape, size, surface and ultimate tensile strength. An experiment-based analysis is conducted to find the factors, responsible for quality and also to find an appropriate level of these factors that will enhance the quality of the FDM process. External quality is built and enhanced through popular seven tools of quality, likewise internal quality characteristics are enhanced by optimizing the process parameters, using popular tool of optimization, grey relational analysis (GRA). In this work, quality is achieved, through various attributes and parameters. Reliable and established quality techniques, known as seven quality tools, are synergistically combined with grey relational analysis to optimize process parameters. Application of the seven quality tools indicates that quality of the product is stable and within specified limits, and hence, the specimens produced have good quality. Process parameters, print speed, infill density, temperature, layer thickness and shell are responsible for quality of the product. An appropriate level of input parameters has been determined, in order to achieve good external and internal quality.