Gerhard Hetzler, engineering manager at Smiths Machine, has first-hand experience with the company’s single-platform approach, and the continuity it provides manufacturing functions like post, machine simulation, NC code, and control functionality.

While the Siemens 840D sl control has evolved in significant ways over the years, Hetzler said these changes have served only to accelerate the performance of the programmers and operators, rather than impede them with new and different procedures. The control platform also gives Smiths Machine the freedom to create custom cycles that can be copied and shared from control-to-control, and so machine-to-machine.

“I’ll give you an example,” said Hetzler. “To catch occasional entry errors on the tool management side, we created a cycle that checks the length of the tool and within a specific tolerance. So within in a matter of milliseconds, the control compares that value to what was entered in the tool management side, and if the tolerance is exceeded by 2mm, the control immediately stops the machine.”

Hetzler said another advantage resulting out of the DMG and Siemens relationship is the continued simplification of complex cutting operations, especially in the area of angular milling heads.

“Siemens has come a very long way to improve the cycles and support related to milling heads,” Hetzler said. “Aerospace requires a lot more use of angular milling: Even a five-axis approach can’t do it; you need an angular milling head. I would put this on the top of my list of the advantages DMG and Siemens have developed. And this relates to another important development, Siemens NX.”

Siemens NX software integrates CAD, CAE and CAM, encompassing all areas of tooling, machining, and quality inspection, to accelerate parts production. NX has become integral to Smiths Machine’s CNC platform because it supports part planning through manufacturing, with the prevention of errors and related costs.

“Our ability to develop all of our own post-processors in house is supported by Siemens NX,” Hetzler explained. “We set up our angular milling heads in NX, so we can post the G-code before we even send it out to the machine.”

An early introduction to the effects of NX came when the organization discovered it needed to write code to produce an especially challenging aerospace landing gear. The code took six-weeks to program manually — before the programmers learned that they could do the same task using NX in just nine days.

“Siemens knows five-axis machining and NX is a Siemens product that leverages five-axis,” Hetzler said. “As an example, we can do three-plus-two axes work in NX. There is a cycle for that called Cycle 800. So when NX outputs the NC code, the machine then also understands it. Other control brands will have a cycle that can be made to work, but they are a lot more problematic. We are talking about managing the change of plane, a concept that has been around for a long time and was always problematic to do. Now, Cycle 800 in NX does it all for you.”

Hetzler said Cycle 800 makes programming the change of plane easier, faster, and with higher accuracy than traditionally calculated methods. “We would normally round off after the third or fourth decimal,” he recalled. “Now, the control calculates to nine decimals. When you start talking in terms of microns, especially in the aerospace industry, it makes a huge difference. And, this difference has been fully implemented by DMG. They have invested a lot of time and money to make sure from their side that Siemens NX and Cycle 800 work 100% of the time.”