SLA, FDM, etc… usually makes the final part. Soft tooling is basically silicone molding created from the final part. Typically it works great and will pick up every detail, but I’ve run into problems injecting wax into soft tooling. Pouring with only gravity usually doesn’t work. I think a very small, enclosed turbine wheel would be nearly impossible with silicone molding from a pattern, but you never know. Another method is to take the CAD model and design the Mold from the CAD file. Then you build the Mold from one of the above methods and inject the wax. This really produces a very nice pattern, but is time consuming to say the least and requires some high-end CAD program (Pro/E, Solidworks, CATIA) and skills. I’m actually doing this right now for castings with Stellite and Inconel. Good stuff, great technology!