FDM Technology: Overhangs versus Layer Height Printability Performance Correlation

FDM (Fused Deposition Modelling) is the most popular 3D printing technology worldwide due to its simplicity and low costs. One of the key points of FDM is the need for supporting material to realize the overhanging features. In general, however, both in the case of printing supports with the same material as the part and in the case of printing with soluble supports, there is a high waste of material and a significant increase in the printing time to get the finished part. One of the fundamental parameters for generating supports within the slicer software is the so-called ''support overhang angle'', which consists of the maximum achievable angle beyond which the slicer generates supports. The other key parameter in FDM printing is the ''layer height'', which directly determines both the quality of the final part, its strength, and the printing time itself. This paper will therefore attempt to investigate the relationship present between ''layer height'' and ''support overhang angle'', bringing some examples of how with proper layer height one can significantly reduce support generation, wasted material and in some cases also printing time.