Fortify has developed a novel approach to injection molding using 3D printed inserts. The advantages of this approach is that inserts can be ready to use within a few days, and at a fraction of the cost of machined aluminum or steel tools. By reinforcing the 3D printed parts with ceramic fiber, tools are able to withstand the rigors of the injection molding process, provided that users modify their procedures a bit from their experience with steel and aluminum tools. The Best Practice guidelines in this document are provided to help users get the best results from this new process.