Design for manufacturability (DFM) is the concept of developing and designing parts for efficient, cost-effective manufacturing. The end goal is to create a better product at a lower cost that is relatively easy to manufacture. Machinists are more than familiar with this idea. Design for manufacturability has been part of the machine shop lexicon for generations, as machinists have historically been responsible for figuring out how to cut, polish, hold and finish a part to match its design.
DFM takes a number of factors into consideration to optimize the process of making a product. The concept has also changed over the years to accommodate increasingly globalized supply chains and the ever-evolving market, which has been trending toward more customized products.
During product design and development, engineers must consider not just a product’s life cycle and intended use but also how the processes are required to manufacture the part—such as CNC, injection molding, selective laser melting (SLM), or any variety of specialty processes and assemblies—will be impacted by the part’s design.
How to Improve DFM Performance
Design engineers often find themselves relegated to a desk, especially in our increasingly digital world. Lacking a valuable hands-on connection to the products they are designing, engineers often run into challenges with early-stage manufacturing, as well as when a product enters full production. A typical issue occurs when a product becomes challenging to produce and gets redesigned by a committee to streamline it for manufacturing. This challenge of disconnection comes in two flavors: separation from the physical process of manufacturing and the rapid expansion of abstract, decentralized supply chains.
These supply chains are complex webs of interconnected external organizations and internal departments that work together to unite materials, components and parts for delivery to an end user or customer. This complexity has resulted in many design engineers being removed from the sourcing process. Yes, specifying components may be part of the engineer's job description, but the push for cost savings means that sourcing is often done by a purchasing specialist after the part or assembly is designed.
“I really would love to see design engineers work on a manufacturing floor and in logistics. And manufacturing people work in design and engineering,” says Sandy Cox, the CEO of Austin, Tex.-based SLC Consulting Group and a former engineer and supply chain director in the semiconductor industry. “The more we can cross-pollinate people in these different roles, the more we’re going to share this learning and simplify the DFM process.”
The digital revolution has amplified this disconnect, often keeping engineers chained to their workstations. Even if manufacturing hasn’t been outsourced, many engineers don’t walk the factory floor or communicate with machine operators, which can lead to a general lack of understanding about the practical limitations of the manufacturing process. It could be argued that design engineering has become more conceptual than hands-on, and the way that engineers are being educated is adding to the issue.
“There’s a massive number of students coming out of academia with mechanical engineering degrees. They don’t have a chance to walk a plant, walk a facility, walk a machining cell or a stamping or molding plant,” says Mike Tummillo, cofounder of Prismier, a contract manufacturer and job shop in Bolingbrook, Ill.
Tummillo says that navigating the need for DFM is a challenge for businesses like his. Customers will bring a designed part that simply can’t be manufactured as is. “That’s a dance in our industry because of how much time and effort we put forward. We like to say we’re paid to make parts, but there’s a big overlap. Through the years, we’ve identified the potential time-sucks and put design for manufacturability and design for assembly efforts there.”
Tummillo also credits some of his company’s DFM success to Assist 2 Develop, a San Diego-based organization that crowdsources solutions to designing, engineering and innovation challenges. Assist 2 Develop hosts open innovation challenges that help provide access to a wide knowledge base for product development and DFM. These open innovation challenges allow firms to first gauge potential candidates’ experience with DFM before hiring them, but it also gives recent grads and engineering students a chance to gain experience with DFM.
Design for Manufacturability: The Basics
The first step in DFM is the basic idea of thinking about how to actually make the physical part early in the design process. Obviously, things change as a design evolves, but considering manufacturing early is key.
Next, become familiar with your company’s manufacturing processes. After all, you can’t design for manufacturing if you don’t understand the manufacturing process. Of course, we can’t all be experts in every facet of product development, production and supply chain. That’s why a number of CAD and engineering software companies have already started prioritizing communication throughout their suites.
“CAD is there to design and validate, but design for manufacturability requires more than just design,” says Mike Buchli, partner sales manager expert for 3DEXPERIENCE Works. “It isn’t about just putting together a bill of materials and sending it off.… To properly design for manufacturability, you need communication and collaboration throughout the design and development process.”
Buchli says that a lot of people might see something like the 3DEXPERIENCE platform as just another CAD in the cloud software, but the cloud is about communication. “Design for manufacturability is about getting to that collaboration and leveraging all the metadata that is available at all levels of the design process,” he says.
Both Buchli and Cox agree that there is not a one-size-fits-all solution, but there’s always value in considering production and supply chain when developing a part.
“If you start with considerations for manufacturability at the beginning of the design process, you give yourself so many options for future development,” says Cox. “What’s more, you can’t go back to fix issues, so preparing for the future can save a product line. For instance, if you’re doing government contracts or anything medical, things like that require qualification timelines that are long and arduous. Once you’ve already designed a part and put it into manufacturing … if you have to go back and reengineer it, you will never [recover] that opportunity cost. You have to do it from the beginning.”
Mastering the world of digital engineering is essential to good DFM because it empowers access and communication between all the players. Buchli explains that giving collaborators visibility, wherever they might be in the product life cycle, means that they can provide insights early and often.
Manufacturability Makes Better Products
Engineers and manufacturers are notoriously risk-averse, which can lead to resisting the DFM concept as up-front costs may scare many businesses from having a design for manufacturability mindset.
“Making the consideration of design for manufacturability early means you might give up a couple dollars in cost, but that is nothing compared to the cost of a poor design,” Cox says.
Design for manufacturability adds a sense of universality to your product portfolio. Even small businesses will be able to develop new products or pivot current products to a nimbler process when manufacturing is considered early on.
DFM can be considered in a range of spaces too, which means that you don’t need to change every facet of your business overnight. Something as minor as streamlining your workholding in a mill can shave seconds off cycle times. Using collaborative software to connect manufacturing partners to engineers means that you can make adjustments before the prototype is ever ordered. And DFM helps future-proof the production of your designs so that it’s easy to make adjustments and adapt to changes in shop floor technology and automation.
As the barrier of entry to production continues to get lower (thanks to technology like 3D printing), the need for DFM will grow exponentially. Manufacturing is becoming more customized and unique (more high-mix, low-volume production), which means that more manufacturers will need to take on production for themselves, leveraging designs that optimize the manufacturing process.
Every situation is different, but when you design for manufacturability, the end goal is efficiency and cost savings. Developing products with manufacturing in mind can make automation more effective, diversify your supply chain, and make outsourcing simpler—not to mention make getting future iterations to market faster. DFM creates value and efficiency now, but it may very well be vital to the future growth of any manufacturing or engineering business.