Case Study: Design for Manufacturability

Thorough Preparation Leads to a Better End Product

Developing a new product involves many moving parts, in both a planning and a manufacturing sense. It includes multiple teams and checkpoints designed to ensure a flawless end product. Preparation is a vital part of the product development process, as it sets up the rest of the project for success.

This preparation lays the groundwork for Designing for Manufacturability (DFM), an interdisciplinary team effort through which design goals and concepts are thoroughly reviewed. The DFM process helps mold makers and manufacturers ensure product quality, durability and cost efficiency. Molders and manufacturers can also factor in lead time and mold maintenance to determine how these factors should drive decisions. DFM is the cornerstone for every project EVCO Plastics undertakes.

Why Is Designing for Manufacturability Important?

The design planning stage is the most opportune time in the development process to consider how the end user wants the product to function. A better understanding of how it will be used allows for a more robust design, provides a higher quality advantage and ensures efficiency.

The product plan and design typically lock in about 70 percent of what the actual product cost will be. This means that identifying cost-efficient materials and development plans needs to take place prior to production.

Increase Competitive Advantage

DFM plays an important role in client competitive advantage. Along with offering potential cost savings on both capital equipment and piece price, early considerations for material selection, including alternate options, can give a speed advantage and ensure high quality.

One example of a checkpoint in the DFM process is Failure Mode Effect Analysis (FMEA), a regimented method of calculating the likelihood of a product failure, in what area and at what level of seriousness. FMEA takes place after the initial design is complete. Mold makers and manufacturers like EVCO look at the design through the customers’ eyes and identify potentialpitfalls in making the part.

Improve Efficiency

Material selection consideration, including alternate options, takes place at the start of the DFM process. Although this may make for a slightly slower start time than jumping right in, it speeds up the overall process as kinks are worked out ahead of time at specific checkpoints. This process works because it solves problems up-front instead of later in the project, which can lead to unexpected costs and delays.

One checkpoint is the Advanced Product Quality Planning process (APQP), which focuses on the robustness of the design. APQP helps mold makers and manufacturers better understand customer needs, provide feedback and ensure the design is within process capabilities. Combined with FMEA, it also helps mitigate failure modes and provides verification and validation process standards.

DFM & EVCO PLASTICS

EVCO Plastics is deeply entrenched in DFM and follows five key considerations to ensure successful DFM. All steps work together in tandem and must be conducted on parallel paths to achieve success:

1. Part Design and Customer Involvement »

Early customer involvement is vital to a flawless end product. The customer has unique insight as to how the end user will need the product to function and can help better determine how specific features will play a role in functionality. Early customer involvement also provides an understanding of the environment the end product will live in and helps anticipate any factors that may inhibit proper functionality. Based on the specific environment, manufacturers are able to identify the most durable and resistant materials.

2. Mold Design & Build »

Mold design should take efficiency, longevity and performance into consideration. The common factors include how the mold will be built, at what cost and any options that may lower the cost. The length of the manufacturing process is an important factor, as it determines how durable the mold needs to be to last the length of the program while keeping maintenance at a minimum.

3. Molding Process »

The molding process is developed to ensure the part design allows for robust, maintainable processing windows and part consistency. Through it, mold makers and manufacturers like EVCO Plastics validate injection molding technologies, cycle times and material flow.

4. Metrology »

Metrology is a vital step in the DFM process. During this stage the feasibility of each tolerance and dimension is reviewed, with the goal of ensuring the long-term statistical capability of critical and major dimensions. Methods of measurement are identified for suitable reliability and repeatability to support validation and production of each product. Based on the outcome of the quality assurance planning activity, critical steel dimensions will be fabricated in a steel safe condition to allow for minor adjustments and molded part capability.

5. Automation »

This step determines the automation requirements for repeatability to meet target part costs or volumes. It’s also the point at which to decide if the design needs to be modified to allow for ease of automation upstream or downstream.

Program Management

EVCO’s typical DFM process begins with an initial one- to four-hour meeting either in person or via teleconference. From there, planning and production are set into motion:

1. Timeline is established
2. Customer sends electronic design files
3. EVCO reviews files internally and creates a feedback document, which is presented to the customer. During this time, merits and drawbacks of the features and proposed changes are discussed. From this, customers are able to understand concerns and potential issues
4. As needed (or as requested), EVCO provides either a prototype made on a 3D printer or an alpha/beta part for testing
5. After approval, EVCO moves forward with production, holding weekly check-ins with the customer

Production and Development Timeline

DFM in Action

Situation »

A large paper company came to EVCO Plastics to partner on a concept for a napkin dispenser, which was originally made out of sheet metal. The customer wanted to make the switch to plastic in addition to incorporating new features for consumers.

EVCO Plastics held a series of client meetings with their marketing, design, purchasing and quality staff to present different options and costs. EVCO Plastics factored in options including material type, timing for making and assembling the parts, purchased component options and tooling. At each meeting EVCO Plastics worked with the customer to review decisions that would impact budget without compromising the quality and functionality. At the same time, quality planning took place to discuss the important features and performance of the parts.

Actions »

When the customer selected the preliminary design, EVCO Plastics developed an SLA prototype so the client could see what a part would look like and how it would function. Quality planning discussions and part performance took place at the same time. Following review of the prototype, EVCO Plastics met with the customer to make any final adjustments before production.

Results »

Through the DFM process, EVCO Plastics was able to cut 30 percent out of the part price and 30 percent from the overall tooling budget, while incorporating the desired features for the napkin dispenser. Processes vary in time frame and complexity based on customers’ needs, but ultimately EVCO Plastic’s DFM process drives down cost and improves quality and manufacturability