Quantifying the Role of Part Design Complexity in Using 3D Sand Printing for Molds and Cores

3D sand printing provides a means to fabricate molds and cores without the need to fabricate patterns and core boxes. It is desirable to understand when to use this evolving advanced technology versus conventional pattern making. This analysis evaluates this question by examining the cost of molds and cores as a function of part design complexity quantified by a complexity factor. Two case studies are presented where the complexity of the castings is systematically varied by changing the geometry and number of cores. Tooling costs and fabrication costs are estimated for both 3D sand printing and conventional pattern making. The breakeven points are identified, and it is shown that 3D sand printing is cost-effective for castings with complexity factor values greater than that of the breakeven points. For low volume production of these castings, 3D sand printing is shown to be cost-effective for low quantities (<45 parts) of castings with lower complexity. However, it can also be very cost-effective for casting with higher complexity even at quantities of 1000 units. Since breakeven point is sensitive to the cost of 3D sand printing, lowering the materials and operations costs can significantly improve the cost-effectiveness of 3D sand printing for varied production volume and part design complexity.