With customers such as Pratt & Whitney, General Electric, Honeywell, Hamilton Sundstrand, Siemens Westinghouse, Rolls-Royce and the U. S. military, Danville Metal Stamping Co. Inc. (Danville, IL) obviously has to supply top quality.

Danville Metal Stamping Co.'s manufacturing processes include forming, welding, machining, heat treating, electro-chemical grinding, sand blasting for optical improvement of products, sheet metal fabrications, engineering with UniGraphics and hydro forming for reverse formed parts up to 35 inches part size. The company started with conventional measuring devices such as height gages and calipers and later moved to projectors. Around 1985, the company bought its first coordinate measuring machine (CMM). The company also uses fluorescent penetration inspection (FPI), such as X-ray inspection. Its quality lab has grown to 5,000-square-feet and the company is certified for several quality, testing and inspection processes. Its batch sizes are not very large for its R&D Department, and CMM system administrator Scott Bean generally measures 1 to 2 parts per setup. Production quality checks are usually done on small series of up to 20 or 30 parts, which also is its typical manufacturing batch size.

A complex part rests on an Alufix fixture, leaving plenty of room for measuring the part. Source: Witte LP
Danville Metal recently began using the Alufix modular fixturing system, with great success. "Everything always fits, with the same accuracy and repeatability, creating enormous reliability in the system," says Bean, who measures a range of 100 to 125 different parts such as air foils, de-icing shields for helicopter engines and turbine engine nozzles, ranging in size from 1.5 inches to 18 inches by 12 inches.

Sometimes parts turn up again and then repeatability of fixturing becomes an issue, particularly since parts are measured in true position, according to drawing orientation. "Repeatability is very important and Alufix has proven itself consistent over the years, no matter if I use the same elements as last time or different ones," Bean says. "Before I start to do the setup, I know it doesn't matter which parts I use as they are all interchangeable. They all fit and are all machined to the same tight tolerance. Not only on paper in literature but also in real life. I know I can expect the same good quality every time."

Low storage requirement is important, too. They have one cart that holds material to measure up to 125 parts. But they did not purchase all of their parts at once-they pieced parts together month after month, creating a dedicated Alufix 25 set for Danville Metal to work with


The variety of available parts allows operators to develop their own fixturing style-Bean's favorite is assembling base plate setups. They often mount AF25 base plates upright to create a rigid right angle/vertical plane. "The price for the base plates is well worth it. Together with other system components it is the most flexible fixturing system I know of or have seen," Bean says. Sometimes dedicated self-machined components are added to their fixtures for special jobs. They use an Alufix plate as a base to hold a gage ring to qualify their disk probe in a horizontal or vertical plane.

A quick to assemble Alufix holding fixture improved productivity at Danville Metal Stamping Co. Source: Witte LP
Comparing an Alufix fixture setup to how Bean started out-using basic fixturing elements such as cubes, 1-2-3 blocks, clay, hot glue, tape and no ability to fix non-prismatic parts at all-he saves at least 30 minutes per setup which goes right over to the actual time where a manufactured part can be checked. "Not even talking about improper fixturing with tape and that the part may be moving, resulting in inaccurate measuring results," he says. "Now, looking at four to five different setups in a 10-hour day, I can easily say, not only having reduced the setup time, this time saving actually enables Danville Metal to check that one more critical part each day. Two and a half hours each day adds up if you look at a week, a month, or even a year. It's all about raising the productivity." Now it takes him about 10 minutes to assemble a fixture setup, on which he can always quickly adjust or move any support to a different position.

Not only that, but they have actually had more reliable and repeatable measuring results. This has allowed Danville Metal to maintain and improve their quality, which is extremely important for their customers.

Danville Metal Stamping Co.

(217) 446-0647