FREE (or Low Cost) Design Review

Posted by Bob Duffy on August 9, 2010 in Design, Device Tips

Design Review, Free Design Review, Low Cost Design Review, QSR, Suppliers

Having spent many years working for a Supplier of electronic assemblies, I have a real appreciation for designs that allow people to provide parts and assemblies that meet Customer needs and expectations. I also know how much we appreciated the opportunity to give valuable suggestions to improve our Customers’ designs.

An often overlooked resource for Design Reviews are a company’s Suppliers.

I ought to pause here and put in a small plug for the term “Supplier” versus “Vendor”. One of my mentors used to say, “Vendors sell peanuts at the ballgame. Peanut Suppliers back the semi up after every home game and deliver truckloads of peanuts.” The point is that “Vendors” make 1-time sales with little or no thought of future business. Suppliers provide ongoing goods and services and recognize that every delivery can dramatically affect future business. So I prefer the term Supplier.

There are several ways a company’s Suppliers Design Review can be utilized in this area:

1. Provide input to designers regarding the capabilities and limitations of anticipated fabrication, assembly and test processes (process capability)
2. Review preliminary designs for clarity and completeness as well as process capability
3. Participate in formal Design Reviews (“any specialists needed”)

An added bonus is that long term Suppliers may even provide these valued services at little or no cost, knowing that improving designs for process capability makes them better able to provide quality parts and assemblies. And even if you have to pay for this kind of design review, there may be no better expenditure in terms of the long term improvements to quality and product cost.

On a project I led a few years back, we knew early on that the external housing would be injection molded. I asked the Team, “do we have an injection molding Supplier who has consistently provided quality at reasonable cost?” They responded, “that would be XXX Plastics”. So I contacted XXX Plastics and arranged to have their head Tooling and Molding guy attend our weekly 1-hr. design meetings for $150/hr. He thought I was crazy since we had barely started the project and were only doing concept designs with our Industrial Designer. The guy said nothing for the first 5 weeks as the design moved from rough concept to early part concepts. During the meeting at week 6 when we were discussing potential parting lines between the upper and lower housings, he uttered these six words: “that will be tough to mold”. The ensuing 15-minute discussion probably saved several thousand dollars in part and tool redesign, not to mention several weeks of schedule. Would you spend $900 for that?

Here are a few ideas you may already be using to get valuable expertise from your Suppliers:

1. Have your Supplier participate in early concept design sessions where designs are not “set in stone” and their influence is usually easier.
2. Have your Supplier review your drawings to ensure that all the information they need is on the drawing.
3. Have your Supplier write down (or dictate) the capabilities and limitations of various aspects of the process they would use to provide parts or assemblies you’re designing. These often are stated as “Rules of Thumb” that encapsulate years of experience and wisdom, and can easily be turned into written “Design Guidelines” or even “Design Rules”.
4. Have your Supplier participate in formal Design Reviews as specialists. The QSR even suggests this when it says “ensure that participants at each design review include representatives of all functions concerned with the design stage being reviewed and an individual(s) who does not have direct responsibility for the design stage being reviewed, as well as any specialists needed” [21CFR820.30(e)].
5. To overcome the potential reticence of Suppliers to give feedback on designs (for fear of being viewed as “criticizing the design”), specifically ask questions such as:
   1. “Are there aspects of the design that add cost above lower cost alternative?”
   2. “Are there aspects of the design that decrease yields compared to high yield designs?”

Ultimately, matching designs to process capability results in high yields and low part/assembly cost, which often correspond to reliability and lower product cost, which then contribute to Customer satisfaction and thus, quality and business success. And Suppliers are a key link between design and process capability.