Your Ultimate Guide to Design for Manufacturing (DFM)

The product development journey is rewarding, but it’s not without its challenges. One of the most critical aspects of this journey, and one that can make or break your product’s success, is Design for Manufacturing. As seasoned industrial designers, we’ve seen firsthand how DFM optimizes production, cuts costs, and boosts product quality.

In this guide, we’ll share our expertise on DFM best practices, common pitfalls to avoid, and how to leverage DFM principles to create better products more efficiently.

Table of contents:

• What Is Design for Manufacturing?
• DFM Benefits
• Design for Manufacturing Principles
• DFM Best Practices
• Examples of Design for Manufacturing
• FAQ

What Is Design for Manufacturing?

Design for Manufacturing, or DFM, is the process of examining how to make a product easier, faster, and more cost-effective to produce without compromising on quality or functionality. This process involves considering various factors such as materials, manufacturing methods, assembly techniques, and the capabilities of the production facility.

DFM is critical for creating products that can be produced at scale efficiently and profitably. Without DFM, you risk ending up with a design that looks great on paper but is a nightmare to actually manufacture, leading to production delays, quality issues, and skyrocketing costs.

At StudioRed, we often start DFM conversations before a project officially kicks off. By considering manufacturing constraints and opportunities early, we can save significant time and money down the road.

DFM isn’t just a one-time activity — it’s a proactive, iterative process that spans the entire product development lifecycle. It starts with the initial concept and continues through design, engineering, prototyping, and production. At each stage, DFM considerations play a crucial role in shaping the product’s design and ensuring its successful transition from concept to reality.

It’s important to note that DFM is not a standalone concept. It’s closely related to other design methodologies, such as Design for Assembly (DFA). While DFM focuses on optimizing individual parts for manufacturing, DFA concentrates on making the overall assembly process more efficient. Together, these concepts form what we call Design for Manufacturing and Assembly (DFMA), a holistic approach to product design that considers both manufacturing and assembly aspects.

DFM Benefits

Implementing DFM principles can have a massive impact on the success of a product. Here are some of the key benefits we’ve experienced firsthand:

• Lower production costs: Optimizing designs for manufacturing can reduce material usage, minimize waste, and streamline production processes. This can lead to significant cost savings, especially at higher volumes.
• Reduced risk: DFM helps catch and correct potential manufacturing issues early before they turn into expensive production problems.
• Faster time to market: Considering manufacturing early on helps avoid major redesigns later in development. This can shave weeks or months off product launch timelines.
• Improved product quality: DFM helps eliminate design features that are prone to defects or variability in manufacturing. The result is more consistent, higher-quality products.
• Enhanced reliability and maintainability: DFM principles often lead to simpler designs with fewer parts. This typically results in reliable products that are easier to maintain, service, and repair over their lifetime.
• Increased production flexibility: A DFM-optimized design can be more easily adapted to different manufacturing processes and scaled up or down as needed.
• Improved communication and collaboration: DFM fosters better communication and teamwork between design, engineering, and manufacturing teams.
• Increased innovation: DFM encourages creative problem-solving to optimize designs, often leading to innovative solutions.
• Improved sustainability: Optimizing material usage and manufacturing processes can reduce waste and energy consumption.
• Greater customer satisfaction: By offering higher-quality products delivered faster and at lower costs, you can exceed your customers’ expectations and boost loyalty.

Design for Manufacturing Principles 

By understanding and applying DFM’s core principles, you can create designs optimized for efficient, high-quality production. These principles form the foundation of our approach to DFM at StudioRed and have proven invaluable in countless projects.

1. Minimize Part Count

Think of product development as a puzzle — the fewer pieces there are, the easier it is to put together. The same concept applies to manufacturing. Each part of your product represents a potential point of complexity, cost, and failure. Minimizing part count means:

• Decreased material costs
• Fewer components to source and inventory
• Reduced quality control steps
• Minimal assembly times
• Less opportunity for defects or errors

At StudioRed, we always challenge ourselves to look for opportunities to combine multiple functions into single parts or eliminate unnecessary components. For example, instead of using separate fasteners, can we design snap fits or living hinges that are integrated into the parts themselves?

Of course, there’s a balance to strike. Overly complex multi-function parts can sometimes be more difficult or expensive to manufacture than multiple simple parts. But in general, a thoughtful reduction in part count pays dividends in manufacturing efficiency.

2. Standardize Parts and Materials

Opt for off-the-shelf parts whenever possible to avoid reinventing the wheel with each new project. This streamlines your inventory management, cuts procurement costs, and ensures consistency in production. Reusing the same parts across multiple products also creates economies of scale. By avoiding custom-made components, you can eliminate the time and cost of tooling and setup.

We encourage our designers to start with standard parts and only move to custom solutions when absolutely necessary. It’s also valuable to develop internal standards for commonly used components across product lines.

For materials, we default to widely available options that our manufacturing partners are experienced in working with. Uncommon materials may sometimes be necessary but often introduce additional cost and complexity.

3. Modular Design

Modular design involves creating independent subassemblies or modules that can be easily put together to form the final product. Imagine your product as a LEGO creation — a collection of individual bricks that come together to form a cohesive whole.

By breaking down your product into smaller, self-contained modules, you create a flexible system where each module can be manufactured and tested independently. Just like LEGO bricks, these modules can then be easily assembled and disassembled, allowing for customization, streamlined repairs, and faster upgrades without scrapping the entire product.

4. Ease of Fabrication

A core tenet of DFM is designing parts to be as easy to fabricate as possible using the available production processes. This may involve adding draft angles, adjusting wall thickness, or optimizing geometry for the specific manufacturing techniques you’ll use, such as injection molding, sheet metal stamping, CNC machining, or 3D printing.

Whenever possible, choose fabrication methods that align with the capabilities of your manufacturing partners. Avoid pushing the boundaries too far beyond industry norms, as this increases risk and cost. Instead, aim for a design that plays to the strengths of the factory.

For example, if a client only produces a hundred devices a year, they might prefer we use sheet metal parts rather than invest in an expensive injection molding tool. Conversely, for clients producing thousands of units annually, injection molding becomes more cost-effective and allows for more complex surface development.

5. Optimize Assembly

While this principle starts to blur the line between DFM and DFA, it’s a fundamental consideration to a future-proof design process. Assembly optimization includes:

• Designing parts that are easy to align and assemble from a single direction (ideally top-down)
• Using symmetrical parts to reduce orientation issues
• Incorporating self-locating features, such as tabs, slots, or grooves, to minimize handling
• Including self-fastening elements, such as snap fits or press fits, to eliminate the need for additional fasteners like screws or adhesives
• Minimizing the need for specialized tools to reduce tooling costs and improve production line flexibility

In a recent project for a self-checkout system, we asked the manufacturer for input during the design phase. During their review, they suggested several improvements, such as adding wire clips to manage cable routing. They also ran a mold flow analysis, which checks how plastic is injected to help prevent sink marks and warp. This feedback allowed us to update our files before investing in tooling, saving time and money.

6. Tolerances and Specifications

While it may be tempting to specify extremely tight tolerances everywhere, this level of precision is often unnecessary and expensive to achieve consistently. Instead, be judicious in how you apply tolerances to the design. Allow looser fits where possible and only tighten up on critical interfaces. This reduces rework and scrap rates while keeping costs under control.

We perform a tolerance analysis to check that parts will fit together correctly, even accounting for the worst-case scenarios of manufacturing variations. For instance, we might run an analysis to ensure that a plastic part coming out of a mold with a tolerance of plus or minus a few thousandths of an inch will still fit properly with other components without gaps or interference.

DFM Best Practices

Through decades of experience at StudioRed, we’ve developed a set of best practices that ensure the successful implementation of DFM principles:

• Involve manufacturing partners early in the design process: We often seek input from manufacturers before we even start designing. By involving them from the start, we can identify potential issues before they become costly problems. This collaboration helps us understand manufacturing constraints and gives us the opportunity to optimize designs for production.
• Conduct DFM reviews at key milestones: We hold regular DFM reviews throughout the design process. These reviews bring together designers, engineers, and manufacturing partners to evaluate the design from a manufacturability perspective. 
• Use DFM simulation tools to evaluate designs: Modern CAD and simulation tools offer powerful capabilities for evaluating designs from a manufacturing perspective. At StudioRed, we regularly use tools for mold flow analysis, finite element analysis (FEA), and tolerance analysis.
• Create prototypes to validate DFM decisions: While simulation tools are incredibly useful, there’s no substitute for physical prototypes when it comes to validating design decisions. We often create prototypes at various stages of the design process to test manufacturability, assembly processes, and overall product function.
• Collaborate closely with suppliers: Suppliers can and should be valuable partners in the DFM process. We tap into their expertise on things like material selection, part geometry, and assembly methods to inform our design decisions.

Examples of Design for Manufacturing

Let’s examine some real-world Design for Manufacturing examples from our work at StudioRed. These illustrate how DFM principles can lead to significant improvements in product design and manufacturing.

Cable Box

In a project for a national cable company, StudioRed was tasked with designing a set-top box. During a design review, the manufacturer suggested we flip the printed circuit board (PCB) upside down to enable “in-process testing.” This meant testing could be done on the manufacturing line without additional fixtures, significantly reducing costs.

The change required about 30 hours of CAD rework but saved significant time and resources in the long run. Had this DFM input been received later in the process, the redesign effort would have been much greater.

Sheet Metal Assembly 

In a sheet metal assembly project, StudioRed was faced with a decision on how to connect two parts to form a “T” shape. While screws, spot welding, or rivets were options, our partner, a major computer manufacturer, recommended something we hadn’t considered — a toggle lock. This simple change, incorporated directly into the metal stamping process, proved more cost-effective than other joining methods and eliminated the need for additional assembly steps or equipment.

By collaborating with the manufacturer and leveraging their expertise, we avoided the need for new files, drawings, and potentially even additional prototype and testing rounds.

Small Wearable Device 

A client approached StudioRed with the challenge of redesigning a wearable ring with embedded electronics. They had a very specific price point in mind and an ambitious production goal. Their existing ring design was expensive to manufacture and had a high failure rate due to tight tolerances and complex machining processes.

Recognizing the challenges of thin-walled, high-tolerance parts, we reached out to a partner specializing in hearing aid manufacturing. By collaborating with them, we were able to redesign the ring using two plastic parts plated in metal. This change improved the product’s reliability and consistency while reducing costs by over 90%.

By applying DFM principles from the very beginning, we were able to develop a superior design that could be produced at scale while exceeding the client’s target cost.

Streamline Your Product Development Process With DFM by StudioRed

Design for Manufacturing is about approaching product design with a deep understanding of manufacturing constraints and opportunities. At StudioRed, we’ve honed our DFM expertise through years of experience and a commitment to excellence. Our team of industrial designers and mechanical engineers collaborates closely with clients and trusted manufacturing partners to ensure every product we create is optimized for production from the very beginning.

Partner with StudioRed to transform your product development process. Contact us to learn how we can apply our DFM expertise to your next project.

FAQ

You might still have questions about how to implement Design for Manufacturability for your specific situation. Let’s address a few common ones that come up in our discussions with clients and partners.

How Long Does DFM Take?

The DFM process is iterative and never truly “done” until you launch the product. However, the upfront DFM work typically takes a few weeks to a few months, depending on the size and complexity of the project. It’s tempting to rush through it or skip steps to save time, but it’s always worth investing the time upfront to avoid much costlier delays and re-spins later.

How Do You Start the DFM Process?

The first step in DFM is assembling a cross-functional team with representation from design, engineering, manufacturing, quality, supply chain, and other relevant areas. Then, you need to establish the key requirements and constraints for the product, such as target cost, annual volumes, and required materials and processes. This will guide the design effort and DFM analysis.

What’s the Difference Between Design for Manufacturing and Design for Assembly?

Design for Manufacturing and Design for Assembly are closely related but distinct disciplines. DFM focuses on optimizing the design of individual parts for fabrication, while DFA is about optimizing the design of the whole product for putting it together.

In practice, many of the same principles apply to both, such as reducing part count, using standardized components, and leveraging self-locating features. The key is to consider both DFM and DFA together in an integrated way to create a design that’s truly optimized for the entire manufacturing value chain.