Abstract Solid Freeform Fabrication (SFF) platforms such as stereolithography have successfully created rapid tooling injection molding inserts to produce plastic parts. However, the rapid tooling of viable aluminum die casting inserts presents more challenges because of the high pressures and temperatures associated with aluminum die casting. The objective of this research was to optimize the Shape Deposition Manufacturing (SDM) process to produce die cast inserts. SDM is a SFF process which can produce fully dense metal structures with Computer Numerical Control (CNC) accuracy. SDM laser-based metal deposition of tool steel powder was optimized for material properties by a Taguchi based design of experiment utilizing the process parameters of laser power, laser scanning rate, and powder feed rate. An insert was created using the optimized settings and run in a 600 ton die cast machine. The insert was used in the “as deposited” condition without any heat treatments. Over 150 aluminum pieces wsre produced...