Potential and Challenges of Fused Granular Fabrication in Patternmaking

Efficient manufacturing of tooling and patterns is an essential part of a good foundry process. Traditional patternmaking methods have been honed to almost perfection during the years. Additive manufacturing has been growing as an industry and presents many new possibilities for the foundry industry. However, many additive manufacturing technologies do not currently provide usable sizes and scales for foundries to properly use. Fused granular fabrication (FGF) in conjunction with finish machining might provide an answer to this issue, with printing volumes and speeds many times of those compared to filament-based fused deposition modeling printing. In this work, some traditional patternmaking materials are compared to a FGF manufactured one based on polylactic acid and cellulose blend, and their characteristics are discussed. 3D scanning of as-printed geometry shows variations inherent to material extrusion methods, while the final machined state shows comparable results to traditional polyurethane model material. The combination of high-volume material extrusion with machining to final dimensions might allow more utilization of additive manufacturing in patternmaking, especially when combined with high-performance polymer materials.