It seems there’s some truth to the Goldilocks story, at least when it comes to plastic injection-molded part design. That’s because several potential problems related to feature thickness exist, some of which can be avoided by shooting for a “just right” dimensional value, and others by optimizing your design for machinability by a specific set of tools (or endmills) used to machine your mold cavity.

All parts submitted to our advanced quoting system get DFM (design for manufacturing) feedback and advisories, but what if some of those advisories require some remedial design work? No worries! Those advisories provide the info you need to create high quality parts with us, quickly and accurately. This design tip offers up details on some of the most common advisories and helps you move forward before your mold is made and production begins.

Before diving into the nitty gritty, let’s discuss some quick review around nominal thickness of your part design, and what affects that might have on the final molded part. As noted above, improper wall thickness can lead to a host of problems. Very thick parts will lead to cosmetic and structural problems like voiding and warping, while very thin parts may reduce structural strength, or not fill at all. You certainly don’t want that, but even more importantly, walls that are too thick or too thin will make the part un-moldable. As a best practice, it is always critical to design your part for the recommended wall thickness of the material and maintain a consistent wall thickness throughout your part.

Now on to the fun stuff: machinability. We use a proprietary, automated process to manufacture our molds to accelerate the process.  We use standardization and machine connectivity from the time that you upload your part, to the time that the finished part leaves our facility. Standardization drives our speed, but it does come with a tradeoff for product developers optimizing a part for our process: Sometimes we can’t machine your part exactly as you designed it. Here are the common machinability advisories, as well as resolution strategies to ensure that your part design is manufacturable, and you get it fast.