Assessing the Use of 3D Printed Patterns for Use in Investment Casting

Abstract Foundries commonly use wax to create patterns for investment casting. Wax use can lead to material waste and increase the time needed to produce parts, as wax patterns frequently need to be corrected, often by hand. Utilizing 3D printed patterns offers the opportunity to increase the precision of castings as well as reduce material waste, especially within smaller scale operations with custom patterns. Two filaments, polylactic acid (PLA) and PolyCast, were compared. For this investigation, four patterns of differing shape and infill were printed using both filaments. Using the shell method of investment casting, a ceramic mold was created from the patterns. These molds were sintered and poured using gray iron. Throughout this process, the molds and final casting were observed to assess the differences between each type of filament and their viability for investment casting, with less damage observed on the PolyCast molds once the pattern was burned out.