Page 52 - MetalForming March 2013
P. 52
When You Need it Fast
TM TM
In-Stock Items Ship in 24-48 Hours
Call us at
(513) 242-8900
or
1-800-543-1566 www.diehlsteel.com
50 MetalForming/March 2013
www.metalformingmagazine.com
Tooling Technology
digitizing the part dimensional data. This allows us to quickly machine replacement parts when needed. Of course, the real benefit is that we don’t scan until the die has been proven out —after perhaps several trips back to the toolroom for fine-tuning. This way we capture the exact dimensions of the die and all of its subcompo- nents in the working, proven die. Compared to having to start from the original tool dimensions and rework and tryout all over again, we can shave days if not weeks off of a project’s lead time.”
WLS is “Game Changing”
The firm first learned of WLS tech- nology in 2005 when it joined a research consortium to investigate springback analysis on advanced high- strength steels. Along with Ford, Gen- eral Motors and others, Cognitens also participated in the project. “We got to know them and once we took a look at their WLS technology, we knew it was game-changing,” says Haas. “We immediately decided to invest, and now we’re close to purchasing a sec- ond system to further expand our scanning capacity.”
While Atlas doesn’t scan every die, the practice is becoming more and more popular. “A few years ago we scanned maybe 30 percent of the dies we either built ourselves or maintained for other stampers,” says Haas. Today we’re scanning more than half of the dies that come through here, and I can imagine that climbing to 80 percent or more in the next few years.”
General Motors started the recent trend toward more white-light scan- ning of dies, say Haas and Watson, then Chrysler and Ford followed suit. Near- ly every day Watson or the four other Atlas technicians trained to operate the scanner will scan stamped panels and dies.
Scanning finished stamped parts allows Atlas to capture design modifi- cations on current programs made to improve fitup on the assembly lines. “Typically for current automobile mod- els, when we need to tweak a die to
improve panel fitup,” Watson says, “once we get the panel to spec we’ll run a five-panel CMM study, then cre- ate a color map of the panel with the scanner. And we capture the new die surfaces as well.”
We watched Watson run a white- light scan a stamped frame rail. Prior to conducting the scan, he wiped the sur- face with a nonreflective coating to optimize light absorption by the scan- ner’s three synchronized 1.3-megapix- el cameras. He then applied dozens of magnetic reflective dots to the entire workpiece surface. These serve as ref- erence points so that the accompany- ing metrology software can stitch together the series of images created. Each scanned image covers a maxi- mumareaof500by500mmofthe workpiece surface, comparable to some 400,000 CMM data points.
A New Application
Describing a whole new application for WLS technology, Watson describes how some customers have begun to ask him to scan the raw castings before beginning the machining process. Scan data tells them if there’s sufficient mate- rial to make the die or part.
“We find this practice becoming common when die parts have been weld-repaired,” says Watson. “The white-light scan will tell us if there’s enough weld metal there to machine the detail back to spec, or if there’s too much weld metal in an area. This situ- ation would then prompt us to rough- machine that particular area prior to finish-machining.
“For example, in a die crash recent- ly experienced by a customer, a wear plate fell off of the die and, when the press stroked, the plate went clear- through the pad,” Watson shares. “They weld-repaired the pad and brought it to us to machine. We scanned it first, to ensure they had deposited enough weld metal. Sure enough, we found that they needed to add another 10 mm of weld in some areas. A lot of time would have been wasted had we not done the scan and started machining immediately.” MF
