Characterising the variability of multi-supplier material extrusion (MEX) parts: an empirical study

Purpose The aim of this paper was to contribute to the Rapid Prototyping Journal’s “Benchmarking – certification and qualification in AM” theme by investigating the geometric and functional variability of parts produced by a distributed set of material extrusion (MEX) suppliers. Design/methodology/approach This is an empirical study that commissioned the manufacture of a replica 2 × 2 DUPLO® brick by nine MEX suppliers. These bricks were then tested for their interoperability, which analysed their geometric, functional and mass property variability. A selective laser sintering supplier was used as a point of comparison. Findings Inter-supplier brick functionally worked with one another (i.e. allowed for the assembly of the bricks) 74% of the time. Intra-supplier brick functionally worked with one another 77% of the time. Dimensional accuracy varied across dimensions, preventing the use of a single scaling transform as a corrective measure. Variation in variance and accuracy across suppliers suggests that lessons can be learned and shared to improve overall performance. Originality/value Distributed multi-supplier additive manufacturing supply chains are a potential solution to meet society’s needs for responsive and resilient supply chains. This paper reports a first-of-a-kind empirical study to examine whether the current AM supply chain landscape is capable of producing parts to the same quality.