It’s a timeless visual: hammer and saw handles jutting past the worn edges and open top of the carpenter’s traditional toolbox. You wouldn’t build a house without them both. You’d turn the truck around in a heartbeat to get either one if you’d left it behind. They are the right and left hand of the job.

The same can be said of other common tools. In product design and production there are two partners, two halves, two disciplines required to build the best “house” on the block. Each tackles cost and producibility. Yet, unlike the hammer and saw, far too often engineering doesn’t bring them to the same workspace on time. Usually, one gets hurriedly pulled out of the truck bed when the woodworking clearly doesn’t dovetail and building the least affordable, last house up on the block isn’t good enough.

Yes, we’re talking about Lean Manufacturing and DFMA. The concepts and individual benefits are familiar enough. If there’s any doubt remaining about their being the hammer and the saw, or how one goes in the right hand and the other in the left, then we have some sound evidence for you to share with your team.

Below is a link to a paper by Nick Dewhurst titled “DFMA the Product, Then Lean the Process.” Based on work first presented at the 2010 DFMA Forum, this makes one of the clearest cases yet that Lean and DFMA should be handled as companion practices. Using a sample part for analysis, DFMA and Lean are applied separately and together. The integrated DFMA-Lean approach yields the highest return!

So, bring all your tools to the job and remind those around you that the right way is often the easiest way as well. See you at the June Forum for more insights. CLICK here for paper.

Sincerely Yours,

Nick Dewhurst

Manufacture success. That’s the theme of this year’s DFMA Forum at the Crown Plaza Hotel. Manufacturing is what’s behind every thriving modern economy. But it’s a strategy, too, for those on the front lines of product development. How you select your tools and methods, and shape your work culture, decides the future. Boothroyd Dewhurst has invited speakers from a range of industries and companies—Alcoa, Whirlpool, Westinghouse, Microsoft, Boeing and Covidien—to review their successes and challenges in meeting these demands of growth and excellence. Last year, presenters came to the 2010 “Turning Point” Forum with amazing results to report and solid advice for emerging in a lead spot. This year, we want to help you continue to manufacture your success. For the latest on early product costing, supporting technologies, and approaches in design and manufacturing, we urge you to attend the 2011 International DFMA Forum. CLICK here for more information.

Since the time of DaVinci, inventors and engineers have wrestled with aviation design challenges.  Here are a couple for today.  Aeronautics challenge number one:  Build a flying machine that imitates the aerodynamics of a maple seed—a nature-mimicry design problem that has stumped engineers for the past sixty years.  Aeronautics challenge number two:  Fly an unmanned vehicle inside a closed structure—one of the last remaining frontiers in the growing world of unmanned aerial systems (UAS) and vehicles (UAV).  Now, both of these challenges have been successfully solved with one design—a biologically-inspired, robotic monocopter. (Full story)

1.  How widespread are design for manufacture (DFM) practices today among manufacturers?  Don’t all manufacturers use some form of DFM?

Yes, I suppose all manufacturers think that they use some form of design for manufacture today, in that they have it written into their product development processes as a guideline, or as a check-off box of rules in a spreadsheet.  But as a formalized, quantitative aspect of a company’s standard product development and manufacturing process, DFM is probably done quite rarely.  The focus, instead, seems to be on a kind of late-stage part producibility exercise that tackles general ease-of-manufacture issues, coupled with line efficiency improvements.  Such approaches, however, don’t address the situation most engineers find themselves in of having created a proliferation of single parts and complex, expensive assemblies. To affect the total cost to manufacture, decisions need to be made early. Rather than finesse here and there at the end of the design cycle or in production, it’s better to think right away about the whole integrated part structure and how to simplify a product and match it to just the right manufacturing processes. This is where the big savings happen.  Let me provide an actual example. We’re working right now on a re-design project for a company that makes large motorized transportation equipment. They gave us a very simple part to start. It was a 40 mm thick steel plate used to lock out the articulation of a truck. It basically connects between two halves and stops them from rotating. The company is very good at flame-cutting pieces of plate and that was the chosen process.  But they were concerned about the part’s weight and cost, and they wanted alternative ideas.  They’re currently buying that part from a supplier who’s following their routine process method for what seems like a reasonable price. But in reviewing the design and truly understanding what the opportunities are for employing different, competing processes, making some subtle changes in the part geometry and shifting to another manufacturing process saves 35 percent. In addition, the weight of the member is reduced while maintaining the original part’s structural integrity. Real design for manufacture occurs when the part geometry and process choices evolve together based on manufacturing science and not personal or historical decisions.

2.  What can DFMA do for manufacturers?

At its most basic level DFMA can help reduce cost, often very dramatically.  Most companies arrive at DFMA because they’re under intense price pressure in the market and they need to continue lowering manufacturing costs after trying other avenues.  Beyond part cost reduction, other big benefits to costing analysis fall in the area of downstream organizational savings.  We always say to people, “What’s the impact on your business of 30 percent fewer parts in the products you produce?”  Think about the burden you lift from your supply chain group when your designs are efficient and you don’t have as many parts to source, track, reorder, service—and wait for!  There is also the growing recognition that high-performance, simplified assemblies require much less labor, which makes overseas manufacture look less attractive for products shipped predominantly back to the U.S.

3.  How critical is applying costing analysis early in product development?

You have to meet or exceed the engineering specification first.  The product has to work. But second in importance to product functionality is cost. You’re kidding yourself if you think cost isn’t the next thing on the list.  Buyers are looking carefully at the performance-to-price relationship, with quality as an assumed attribute of performance.  Early costing and design simplification are absolutely fundamental to efficient product development and profitability. These two related DFMA practices have to happen either during the conceptual stage or during a thorough rethink of older products. What are the actual costs and benefits of leaning out products that are not designed well in the first place for production and assembly?  Take the example of the equipment company mentioned earlier. They could spend an awful lot of time trying to develop a lean manufacturing process around flame-cutting plate parts and maybe reduce cost by only 3-4 percent.  But there’s a 35 percent cost reduction by changing the process. Lean manufacturing, by the nature of its discipline and because of the momentum against late-stage design changes, will never lead you that far upstream, to the heart and source of manufacturing challenges. When you release poor designs to production–you’ve just handcuffed the manufacturing engineers.  Done together, however, these two approaches are powerful.

4.  How do DFMA and concurrent engineering help break down the walls between design and manufacturing?

DFMA questions and analyses lead design and manufacturing teams to discuss deeply interrelated issues and to recognize the ways in which each group can constructively help the other. Just the idea of asking the questions and getting answers from the software and from the experts in the group is something that helps with breaking down barriers.  But I also think the idea of having information to hand off to one another is important. I can take my analysis of the articulated lock-out part, for example, and send it to the manufacturing people and say, “Hey what do you think about this?” They can then send back their comments, and I can refine my detailed cost analysis and give it to purchasing. With a complete breakdown of the process selection costs by set-up and volume, purchasing can validate incoming bids. If you know that $35 is your estimated cost and you get three quotes back at $24, $31 and $46, which one would you pick?

5.  How can design for manufacture help companies practicing lean manufacturing and/or Six Sigma?

The best answer to that question is, which would you rather undertake: a lean manufacturing effort on a product that has 100 parts— or a redesign of the product that has 50 parts and same or better functionality?  I think the answer to that is pretty clear but not often fully appreciated.  In terms of Six Sigma, the part consolidation program in design for assembly eliminates many of the interfaces that play such a large role in product failure. Again, good design serves the goals of those who work hard to improve manufacturing efficiency and quality.  One long-term consequence of “over-the-wall” engineering is that manufacturing and quality engineers may still not feel empowered enough to influence early design. People also feel they are working too fast to communicate across disciplines and to engage in top-to-bottom innovation. In truth, early design analysis cuts the time it takes to design and make products, and it gives a structured format for manufacturing engineers to voice their knowledge.

6.  Do you have a special module for machinists?

Yes.  We have a quick analysis for non-experts and a detailed machining cost analysis that gets down into the hidden costs of labor and machine idleness and can assess the time needed to complete entire manufacturing runs. There is also a new costing program for dedicated and non-dedicated cells. Our DFM programs allow shops to follow an “as quoted” production process and provide data for consulting customers about design strategies, including the cost of machining individual features. Another benefit of the DFM suite is in knowing what the cost tradeoffs are between the different manufacturing processes and to be able to recommend low-volume machining when the numbers are favorable.

Re-published courtesy of SME


Southco Inc. manufactures latches, hinges, fasteners, inject/eject mechanisms and other access hardware (the “touch points”) for enclosures and cabinets. Over thirty percent of their business is custom work. “We have to make many of our products to customers’ individual specifications,” says Rick Langkamp, Manager of Manufacturing Technology and New Product Development at the Southco facility in Honeoye Falls, N.Y., “and we have to make them at a reasonable price.” (Full story)

Design News editor Beth Stackpole gathers together Boothroyd Dewhurst’s John Gilligan--and DFMA users ITT Aerospace, Raymond, Hypertherm and Whirlpool--for a look at how companies are making dramatic improvements to their products and rolling the benefits of assembly efficiency across their manufacturing enterprises. CLICK HERE for more info.

Additive manufacturing, or 3D printing, as it is sometimes called, is predicted by the Economist, in their February cover story, to be ready to reset the economics of manufacturing. This new “generative” manufacturing process for lower volume products invites customization and innovation, with fewer constraints, labor costs and waste, says the magazine. CLICK HERE for more info.

Reviving American manufacturing has become a central focus for the National Institute of Standards and Technology (NIST), reports Manufacturing & Technology News. Says NIST director, Patrick Gallagher, “The realization here is that manufacturing is a key part of innovation.”  Should Congress agree, helping U.S. manufacturers will become a core mission for the agency. CLICK HERE for more info.

Home | About BDI | Contact Us | Privacy Statement

Questions or problems regarding this site? Please Contact:
Obtain technical support at Want more info?
DFMA and Concurrent Costing are registered trademarks of Boothroyd Dewhurst, Inc.
© 2011 Boothroyd Dewhurst, Inc. All rights reserved.

If you would like to be removed from our mail list, please CLICK HERE

DFMA Insights April 2011