How do you know if your part is a good candidate for metal injection molding (MIM)? The first thing to think about is the quantity of parts you need. At Smith Metal Products, we work with customers looking for more than 25,000 parts per year if they have one design. For multiple designs, we look for over 10,000 parts per year for each design. Small runs of parts do not make sense for MIM with the cost of the molds needed for the process. The second determination depends on the material used to make the part. The typical metals we use at Smith Metal Products include stainless steel and titanium. However, there are many other alloys that we have experience with and others that we would be willing to develop depending on the scope of your project. We cannot use aluminum, zinc, magnesium, or brass. Part size can also dictate the compatibility with MIM. We look for maximum part lengths of three inches or less. However, there are some exceptions. Wall thickness (or thin-ness) may have an impact on MIM viability. The minimum wall thickness that we look for is .020" or 5 mm. We also do not want walls that are thicker than .125" or 3mm. In some cases, we may be able to "core out" these areas in the design for manufacturability process. Part weight is another consideration. Most of the parts we manufacture are under 25 grams, but we use 100 grams as the highest weight compatible with MIM. Why does it make sense to use MIM? If you have higher priced machined or cast components, MIM may be a cost savings. If you are a machine shop, MIM can be used to create blanks and free up machine time for you to work on other projects. Some multi-component assemblies may be combined into a single MIM component. Components made out of expensive materials like Inconel or titanium are good candidates since you do not cut away value material in the MIM process. The metal needed for the part is injected, not cut away from bar stock. If you are considering a part for MIM, please email us at DFM@smithmetals.com and we will evaluate the part.