Limits of 3-D Printing

JUNE 13, 2014

Manufacturers are finding that a revolutionary technology has its limits, writes The Wall Street Journal(June 2, 2014). According to enthusiasts, 3-D printing was supposed to rewrite the rules of how things get built. Forget building new factories, or outsourcing production to China. The compact devices would launch a manufacturing renaissance centered in people’s living rooms and garages. Some makers of 3-D printers don’t argue with the critiques. Devices like MakerBot’s are meant to help designers and engineers test ideas and speed the development of products, not necessarily replace large-scale manufacturing. Continue reading

Car Designers Stick to Clay Models

JUNE 9, 2014

 

When it comes to designing high-tech cars, writes The Wall Street Journal(June 2, 2014), auto makers still depend on clay models sculpted by hand—a craft that goes back to the industry’s early days. Designs for a new car may start with a simple sketch on a cocktail napkin. Sketches get turned over to a digital modeler, who fits the lines of the drawing over a digital rendering of the car’s engine, suspension and other chassis parts. The idea then goes to a clay modeler to be transformed into a series of clay models, usually starting with sculpture 4/10 the size of an actual car. But despite use of 3-D imaging technology that allows executives to see a virtual vehicle, the top brass at Ford won’t sign off on producing a new car until they see full-size physical models.

The pressure to produce new designs more rapidly intensified when competition in the auto industry went global. During the 1990s, auto makers boasted about how quickly they could bring new vehicles to showrooms as they slashed product-development times from 5 years to under 2 years by relying more heavily on CAD tools. The rapid decline in the cost of computing power moved the auto industry closer to a world where the mathematical models of a car’s exterior and interior surfaces could go directly to computer-driven machines that cut dies and molds for production. The problem, says Ford’s design head, is “digital projections can’t accurately show how light will play on a car’s surface.”

Once designers have a model about 60% right, they use an optical scanner to translate the clay scale model into a package of digital data. Milling machine can produce a full-size clay replica in one day. The clay-to-digital, digital-to-clay approach is now common. Designs go back and forth between clay and digital renderings, and are integrated with digital representations of the car’s chassis and other mechanical components.

This post provided courtesy of Jay and Barry’s OM Blog at www.heizerrenderom.wordpress.comProfessors Jay Heizer and Barry Render are authors of Operations Management , the world’s top selling textbook in its field, published by Pearson.

The One Worker Assembly Line

JUNE 5, 2014

At Japanese manufacturer Roland DG, assembling thousands of parts into wide-format printers is as easy as coloring by numbers, writes The Wall Street Journal(June 2, 2014). That’s because Roland DG makes everything from billboard printers to machines that shape dental crowns using an advanced production system known as “D-shop.” Under this method, workers in single-person stalls assemble products from start to finish, guided by a 3-D graphic and using parts delivered automatically from a rotating rack. Every worker is capable of assembling any variation of the company’s 50 or so products.

In 1998, Roland became one of the first companies in Japan to abandon the assembly line in favor of one-person work stalls modeled after Japanese noodle stands. With orders coming in smaller and smaller lots, Roland decided it needed a manufacturing system in which a single worker could build any one of its diverse products. On a recent day, one employee was assembling from scratch an industrial printer that ultimately would be more than twice her size and weigh almost 900 pounds, while another was assembling a dental-crown milling machine.

A computer monitor displays step-by-step instructions along with 3-D drawings: “Turn Screw A in these eight locations” or “Secure Part B using Bracket C.” At the same time, the rotating parts rack turns to show which of the dozens of parts to use. Meanwhile, a digital screwdriver keeps track of how many times screws are turned and how tightly. Until the correct screws are turned the correct number of times, the instructions on the computer screen don’t advance to the next step. The system is so simple, say managers, that nearly anyone can assemble products anywhere. The computer even gives workers a pat on the back at the end of the day, with the message, “You must be tired, and we thank you.”

This post provided courtesy of Jay and Barry’s OM Blog at www.heizerrenderom.wordpress.comProfessors Jay Heizer and Barry Render are authors of Operations Management , the world’s top selling textbook in its field, published by Pearson.