Coping with aerospace manufacturing complexity

Seyer Industries is experiencing rapid growth in its aerospace component manufacturing operations – both ground support and flight components for commercial aviation and defense customers. To keep pace with vast amounts of production and manufacturing process development work, the company is relying heavily on the advanced capabilities of its CAM software Mastercam, by CNC Software Inc., Tolland, Connecticut.

Until 2004, Seyer Industries concentrated primarily on manufacturing parts and assemblies for aerospace ground support equipment. At that time, an important second tier aerospace customer took note of Seyer’s consistent quality and on-time deliveries and asked if the company would manufacture flight parts and assemblies.

“Today, flight components constitute about 40% of Seyer’s business, and that percentage is growing rapidly,” says Mark Seyer, vice president of manufacturing. “Competing for flight parts is a high-risk, high-reward venture because of the heavy investment required in advanced CNC equipment and product development man-hours that are essential to obtaining significant contracts.”

Between 2006 and 2008, driven largely by aerospace work, Seyer Industries nearly doubled in size. Workforce shrank a bit during the lean years of the economic downturn, but today, the aerospace business is robust, and the company is attacking it with 154 kanban-trained workers and multi-axis manufacturing processes.
 

Programming and planning

Ray Gaudette started working in the shop as a machinist shortly after the first influx of flight parts business. Within weeks he was assigned Mastercam programming responsibilities and a few years after that became supervisor of the programmers. Today he is manager of programming and manufacturing planning. He has no complaints about his dual role, since CNC programming and manufacturing planning (engineering) are highly integrated at Seyer.

Gaudette supervises a staff of six planners who take projects from print to final assembly. This work can be very complex, since some of the assemblies going through the shop have as many as 500 parts that must arrive on time from the CNC manufacturing department.

One of the biggest challenges Gaudette faces is orchestrating various streams of work through the shop for production manufacturing, program development, and to expedite special requirements. The company used to have a separate expedite shop that did nothing but unpredictable, fast-turn projects. Now they are integrated with all of the other manufacturing to make the best possible use of manpower and equipment.

There are seven Mastercam programmers, six of whom are proficient in 5-axis programming, and one who specializes in programming a 9-axis mill/turn system. At present, this is programmed conversationally, bringing in Mastercam-generated sub-routines for surfacing and engraving as needed. One of Gaudette’s goals is to perform all of the mill-turn programming in Mastercam, since components made on that system are becoming increasingly more complex.
 

Taming geometric complexity

Using its 5-axis manufacturing systems to efficiently cut parts of increasing complexity is resulting in larger contracts for the manufacturing of aircraft parts at Seyer.

Gaudette says, “The everyday parts we are programming now would have proven a huge challenge 5 years ago. Parts that are hard for us today, we would have considered impossible. Nothing is getting simpler.”

Customers continually present Seyer with new materials, more difficult shapes, and thinner walls that reduce weight without compromising strength. Gaudette explains that the type of toolpath and the methodology chosen can make or break the quality of the part. For example, choosing the wrong toolpath could put stresses into thin walls, which will ultimately warp. Material-aware toolpaths in the most recent versions of Mastercam have allowed Gaudette’s programmers to write better programs that respond to these issues, he adds.

Gaudette believes that the challenges of increased complexity keep the programmers sharp and interested in what they are doing. He cites a number of ways they have engaged with Mastercam to respond to these challenges:

Programming from native CATIA models: More of the work Seyer does for its customers relies on model based definition, with all manufacturing data transmitted paperlessly via the CATIA model.

Gaudette says, “Mastercam’s CATIA translator allows CNC programmers to pull up and work from the native CATIA file with its complete data set including annotations. It’s a big plus for us – reducing risk, saving time, and improving quality.”

Managing multi-axis parts: Gaudette says, “During the past three years, the software’s multi-axis toolpath capabilities have really stepped up. There are much better options now compared to the conventional pocketing routines and swarfing toolpaths. Our guys have commented on these – they really like them.”

Dynamic Motion technology: For roughing operations Seyer programmers rely on toolpaths with Mastercam’s Dynamic Motion technology. These toolpaths continually monitor the condition of the material ahead of the tool and alter tool motions to maintain a constant chip load. This approach simultaneously reduces wear on the tool and stress on the part. It also allows the highest material removal rates the equipment can perform.

Gaudette notes that Seyer is paying less for carbide tools as a result of this approach, but cutting tool cost reduction is not the only or the most important benefit.

“We preset our tools, but guys still make mistakes,” Gaudette says. “When machinists are jumping in and out of the machines to change tools, not only is the spindle down, but more important, if he does something wrong and sets his tool height wrong, we have to scrap a part. So improving tool life is far more advantageous than simply reducing cutting tool costs.”

Morph between two curves: This advanced toolpath automatically blends surfaces between dissimilar toolpaths, so that no tool marks are visible. Sometimes morph between two curves is used to create a more pristine surface that does not require additional operations to meet cosmetic requirements. At other times the morphing process is functionally important such as when it is used to prepare a surface for a subsequent process (for example, shot peening).

In the past it would take many hours to program a 5-axis CNC to blend surfaces in this way. Now it is only necessary to select the boundary between the adjacent toolpaths, and the software generates the morph between curves toolpath automatically.

Clear communication to the shop floor: All of the information machinists on the shop floor need to set up and run a machining operation is communicated in the form of annotated sketches created directly in Mastercam. Machinists call these up at computers near their equipment.

Gaudette says that View Sheets are improving everyone’s productivity by eliminating unnecessary conversations.

G-code simulation: Seyer’s CNC programmers routinely use Mastercam’s backplot and verify commands to simulate tool movements and material removal. However, the ultimate test for a Seyer

5-axis program is a full machine simulation of the G-code.

“This takes a little extra time,” Gaudette says, “but we are not going to put a new program in a half million dollar machine without simulating it first. With the click of a couple buttons, the Mastercam/Vericut interface transmits all the G-code, offsets, and set-up information needed, so we can begin simulating immediately. We usually don’t find tool and holder clearance issues but every time we do a Vericut simulation, we usually find something that we can improve. So, we pop the program back into Mastercam and introduce some changes to make our manufacturing process even better.”
 

Action items

Every department within Seyer has continuous improvement goals. For 2015, the programmers’ goals centered on finding ways to improve CNC programming productivity. There were 10 specific action items ranging from hiring more programmers, to promoting others from within, to relying more heavily on its Mastercam reseller, QTE Manufacturing Solutions, for training and recommendations on how it can take even greater advantage of advanced CNC programming software features. The sense of urgency about achieving these goals is real since Seyer has been awarded three major contracts for aircraft parts involving hundreds of part numbers.

On-boarding these long-term contracts will result in steady business for years to come. However, Seyer assumes a heavy cost burden while programs are being written and initial parts manufactured, inspected, and tested. The company is depending on its programmers’ increased productivity to weave all of the development work through the ongoing stream of today’s paying business.

Mastercam
www.mastercam.com

QTE Manufacturing Solutions
www.qtemfg.com

Seyer Industries
www.seyerind.com