3D Printing Design

Key considerations for manufacturing critical parts

By May 13, 2020
Critical Parts Hero scaled

Critical parts or components are those that, if they fail or become damaged, could catastrophically impact the performance of their applications or could compromise the safety of the end user. Because of this, critical parts are often subject to strict regulatory standards, and some industries have market-specific requirements designed to ensure the optimal function of devices and applications while also maximizing user or consumer safety.

An example of critical parts is ground support equipment in the aerospace industry. These are parts that are used to support the movement and maintenance of aircraft on the ground. Ground support equipment interacts directly with flight-critical components, underscoring the need for ground support equipment that meets the stringent mechanical and safety regulations of the industry. When properly engineered and manufactured, technicians can use these parts safely and confidently in the field, assured of their inherent reliability.

A pintle bearing alignment tool manufactured by Fast Radius and Satair.

Manufacturers of critical parts are expected to consistently create incredibly precise parts that comply with industry-specific regulations, which has often been associated with high production costs and long lead times.

However, developments in additive manufacturing technology have begun to change how engineers approach designing and producing critical parts. There are a number of factors that go into creating practical, high-quality critical parts, and this article will touch on three of them: engineering design, manufacturing process, and materials.

Product design considerations

In order to optimize the design of critical parts and components, there are several factors that need to be taken into consideration. These include the industry, application, and environment in which the part will be used; the potential for foreseeable misuse; and the training and expectation of the end-user.

First, knowing the industry and use case allows product designers to prepare for specific requirements. The medical industry, for instance, follows strict requirements for the use of critical parts and the viable materials allowed to create these parts. Other physical and chemical considerations include moisture resistance level and whether parts can be sterilized with certain chemicals.

By familiarizing themselves with the industry and how the product will be expected to perform in its intended environment, engineers will gain a better sense of how to optimize part design.

This extends to the loads and pressures that the parts will be expected to withstand, as well as how frequently those loads will be applied. If there’s a chance the part could fatigue out, engineers also need to consider the part’s lifecycle in order to tailor their solutions to match.

End-users are another key factor. Consumer products, for instance, tend to demand more intuitive designs than those intended for trained personnel. A knowledge of end-use allows engineers to run risk assessments to determine whether the part could be used in ways it was not intended for, as well as the risks associated with foreseeable misuse.

Manufacturing process considerations

A common myth about additive manufacturing is that it’s only good for prototyping and not for making viable production parts. However, in many cases, additive methods present a better option when it comes to manufacturing critical parts because they allow engineers to create parts with greater ease and efficiency than traditional methods.

Take for example the medical field of microfluidics, which involves tissue and blood sampling, dispensing pharmaceuticals, or dosing small amounts of liquid. The sector relies on components that allow for these sorts fluid transfers — which, in general, cannot be created with conventional modes of manufacturing.

These products are frequently made with additive manufacturing, because the alternative is an involved and costly tooling process that uses injection molding and micro-injection molding. Both of these can take weeks or months to achieve what additive manufacturing can do in a day.

Additive manufacturing in cases like these speeds testing cycles and drastically reduces time to market. Further, while injection molding tooling costs can easily cost a hundred thousand dollars, additive manufacturing methods promise a lower price tag of less than $100 per unit.

Many critical component applications require working with small volumes and precise features. When trying to create these parts with plastic via traditional means, engineers must machine them with extreme precision or create molds into which plastic will be injected, both of which increase production costs and lengthen timelines.

Additive methods, on the other hand, allow manufacturers to make critical parts without molds, so they don’t need to consider how tooling affects minimum feature size or conduct mold flow analyses.

Material considerations

Identifying the ideal properties of critical parts is key to determining which materials are most suitable for a given application. Parts that need to withstand high temperatures will likely need to be manufactured from different materials than those that require a degree of flexibility or impact strength. By outlining the specific stresses, loads, or appearances expected of the part, engineers can quickly identify the material or family of materials that will result in an optimal part for an application.

Additive manufacturing plays a role here, as well. While most 3D printing processes have traditionally required rigid plastics, Carbon Digital Light Synthesis™ allows engineers to use softer materials, such as elastomeric polyurethane or silicone, which can be used for applications that require physically compliant parts that provide dampening, shock absorption, or sealing characteristics.

Developing critical parts through additive manufacturing

Ultimately, critical parts and components must meet two key requirements: they should be able perform according to the requirements of their intended applications, and if they degrade or fail over time, they should do so without causing harm to the user.

Fast Radius works on the cutting edge of engineering to manufacture critical components that have direct impacts on consumer safety. Our customers know and trust that when they work with us, we will provide solutions to  keep their businesses moving at the speed that the economy demands — while guaranteeing parts of unmatched quality that comply with crucial regulations.

Our development team is also available to consult on design processes — and can even apply innovative manufacturing methods to legacy products. Contact us today to get started on your next production run.

Visit the Fast Radius resource center to learn more about the different manufacturing processes we offer — including Carbon’s Digital Light Synthesis™ — as well as the wide variety of materials we work with, including the EPU family.

Ready to make your parts with Fast Radius?