• Engine-Technology   Man 1, Machine 0

Man 1, Machine 0

If popular cinema is any indication, man is still smarter than machine. Sure, he is also smaller, weaker and less predictable, but man still takes the trophy in the brains department — especially when it boils down to making the most of those bigger, stronger, mass-producing chunks of metal. And especially when that man is Machinist Keith Woodhouse of Aero Components.

Aero Components is an advanced contract-machining firm that builds complex and precision parts for the aerospace, medical, semi-conductor and oil-field industries. It’s also the place where Woodhouse has taken cinematic analogy and applied it to the real world. At Aero, he has learned to maximize the company’s existing inventory — its machine-tool lineup and ESPRIT computer-aided-manufacturing (CAM) software by DP Technology — to save countless hours, and even days, of production time.

So, just how much smarter than machine has Woodhouse proved to be? Let’s take a look.

Woodhouse’s challenge began in 2008 with Aero’s acquisition of a Mazak Vortex 5-axis machine tool, a tool adept at producing complex aerospace parts. While the new machine tool made for fast and efficient machining, the task of inspecting the large parts it produced was a tricky one.

Prior to the introduction of the Mazak Vortex, it was standard practice at the company to use a coordinate measuring machine (CMM) to check tolerances of machined parts against corresponding computer-aided-design (CAD) models. “The computer knows what the shape and size are supposed to be and the CMM verifies that the part is within tolerance,” Woodhouse said.

The clock consistently won the race

In a nutshell, CMMs use touch probes to inspect part accuracy by taking measurements in X, Y and Z and comparing them to the corresponding CAD model.

At Aero, in addition to a final inspection performed once parts were fully machined, they were checked by CMM at several points throughout the machining process.

Though Woodhouse continued inspecting parts on Aero’s existing CMM following the addition of the Mazak Vortex, the task had become grossly time-consuming and tedious due to the large size of the parts produced on the Vortex — parts such as those for the new F-35 joint-strike fighter.

For instance, one part that would ultimately be whittled down to 30 pounds at the end of the machining process began as a whopping 650-pound hunk of metal. The race against the clock was made more difficult given the sheer size and weight of the material. Combined with the struggle to properly test and reposition parts, the clock consistently won the race.

“A lot of the time, when you take the part off of the machine and put it on the CMM to inspect it, it’s hard to get it back to the right place on the machine,” Woodhouse said. “If I have to take the part off the machine and take it to the CMM, we are talking hours.”

This constant back-and-forth between the Vortex and the CMM capable of inspecting just one area of a large part at a time added up to dead machine time for both tools. It would often take hours, and sometimes even days, to machine and inspect a part, and 5-axis part features could only be inspected on a CMM to the CAD model.

Woodhouse had to come up with a plan B, and skipping verification was not an option.

“You’ve got to make sure your program and tooling are right before you start cutting on the material,” Woodhouse said. “The material is so big and so expensive that you can’t just scrap a part.” In this business, mistakes cost money and, as the team at Aero is well aware, dead machine time costs money, too.

For Aero, plan B had to include a way to verify parts every step of the way — as they were being machined. And so Woodhouse did his homework. Because buying a new CMM for $75,000 to $100,000 was simply out of the question, he considered a portable CMM arm complete with software and a price tag of about $45,000. However, because it offered no improvements in accuracy over the existing procedure, the arm was a mediocre and pricey option.

Woodhouse then researched part-inspection software and the possibility of a touch-probe in the actual machine tool, but “it is $12, 000 to $20, 000 to do a 3D-vectored probing.”

With steps one and two eliminated, the third step — thinking about how the company could capitalize on what it already had — proved to be the charm: What Aero already had was a Mazak Vortex machine tool and ESPRIT CAM.

Getting more out of the software

“I realized that ESPRIT had a CMM tool feature,” Woodhouse said. “I remembered seeing it, but I had never checked it out.” Upon closer inspection, Woodhouse determined that the CMM tool was a feature they could use to maximize the machine tool, get more out of the software, and think “smarter” than any machine by figuring out how to make existing inventory work better than it ever had.

Aero first purchased Renishaw’s Inspection Plus macros for $1,076 (at just a few dollars less than the two previous choices) to generate programs for part inspections.

Woodhouse then took the X,Y,Z,I,J,K data in the file created by ESPRIT and fed it into an application designed by the team at Aero. “It takes the X,Y,Z points and the I,J,K vector and creates a program using the probing macros that I can put into the machine to inspect parts like a CMM. Basically, we have a great, big CMM now.”

What’s more, the Vortex isn’t the only “great, big” CMM that the company now has.

“Because the probing macros are numbered the same for different controls, I can use the same program on any of our Fanuc or Mazak/Mitsubishi mills or Integrex machines with only minor changes at the beginning and end of the code,” Woodhouse said.

Within 30 minutes, Woodhouse can now create a program that allows him to inspect parts on the machine and generate fairly complex reports on part integrity in relation to design intent. “It’s a huge time saver and it keeps the machine up and running,” he said.

Though the company continues to use its CMM machine to verify finished parts, the ability to operate from the machine tool has saved hours upon hours of production time.

“I always use ESPRIT on really complex parts,” Woodhouse said. “There are parts that would be impossible to program without ESPRIT.” Still, despite the powerful machine tools and the software that drives them, it took a man to pull the whole thing off. To outsmart a challenge, there are times when it takes the willingness to really look at what’s right in front of you in ways that you hadn’t imagined.

And that’s one thing that a machine will never do.

Stacey Wiebe

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