Professor Steve Eppinger Provides Hands-On Demonstration
By Monica Nakamine
December 17, 2002
How many pieces does it really take to manufacture a VHS tape?
LFM-SDM staff members found out on December 17, 2002, at a hands-on workshop and presentation given by Professor Steve Eppinger at the most recent Lifelong Learning Seminar for LFM-SDM staff. Each participant disassembled an old VHS tape and counted its individual parts. On average, most people found roughly 35 pieces. Then, demonstrating the concept of Design for Manufacturing (DFM), Eppinger posed the question: “Can this product be made using fewer parts?”
DFM emphasizes manufacturing issues throughout the product development process. The goal is to reduce production cost without compromising quality. There are three approaches to implementing DFM:
- Organization – cross-functional teams
- Design rules – specialized by firm
- CAD tools – Boothroyd-Dewhurst software
The cross-functional team concept is highly effective since it allows knowledge transfer between different groups, increasing efficiency and productivity. For example, since Team A and Team B understand each other’s job functions and processes, each can take over for or assist the other if necessary, thereby maintaining throughput and reducing stress on employees.
“Cross-functional design teams are the norm today,” said Eppinger. “But 15-20 years ago, they used to be a big deal.”
No matter what the product, there are basic rules that serve as guidelines to achieve DFM. Depending upon the nature of the company and the products it manufactures, these rules are customized in order to appropriately fit the needs of the company and its manufacturing procedures. Below are 10 rules that would apply to a computer manufacturer:
(1) Minimize parts count.
(2) Encourage modular assembly.
(3) Stack assemblies.
(4) Eliminate adjustments.
(5) Eliminate cables.
(6) Use self-fastening parts.
(7) Use self-locating parts.
(8) Eliminate reorientation.
(9) Facilitate parts handling.
(10) Specify standard parts.
According to Eppinger, these rules are fluid and flexible, depending on what the company manufactures. The rules can be adjusted to better fit the nature of the business.
“Rules are generally customized for the manufacturer,” said Eppinger. “What we really care about is not following the rules, but minimizing cost. Rules may be different because cost might be different, but the process is the same.”
To minimize cost, companies must find ways to manufacture their product with the least number of parts, thereby decreasing assembly time and labor involved.
Returning to the VHS tape exercise and taking into consideration the DFM concept, Eppinger posed another question: what is a $0.01 cost reduction worth in this primarily Asian-based industry that creates an annual worldwide volume of two billion VHS tapes? Considering that it only costs 25 cents to make a single VHS tape that has about 35 individual parts, a savings of only one penny is astronomical – about $20 million. That is why DFM is widely used today – to design products as efficiently as possible, with the least number of parts.
After the exercise, Eppinger showed participants a promotional video for the Global Zero. The G-0 was a VHS-like tape that not only had a design scheme that required about 14 individual parts, but was made of recycled materials, manufactured in the U.S., and came in a variety of colors. Because the DVD was invented around the same time, the G-0 never really got off the ground. Regardless, Eppinger used the G-0 as an example to demonstrate DFM in a real-life product.
While staff members frequently hear LFM and SDM students rave about Eppinger’s classes, his presentation provided the staff with a first-hand opportunity to both learn about Eppinger’s expertise and the world of product development.