All About precision

Unique staffing requirements at the Jet Propulsion Laboratory

The six machine shops at the Jet Propulsion Laboratory (JPL) are in the bathtub. In JPL speak, this means that the manufacturing work for its current flagship and frontier missions is almost entirely completed and staffing is at the bottom of a wide U-shaped trough.

Richard Cournoyer, manager of the group, puts today's head count at 30 machinists and two apprentices (with openings for three more). The next major flagship mission will involve sending a landing vehicle to Europa, a moon that orbits Jupiter.

That launch is scheduled for 2020. Between 2014 and 2015, he anticipates the project will be in Phase C - the build phase - and the machinist staff is likely to double.

When JPL rebuilds its machinist staff, Cournoyer will meticulously sift through the resumes of applicants supplied by three contract employment firms. In the past, finding enough qualified applicants was a problem. Most applicants were immediately rejected because they had no experience with Unigraphics, JPL's primary CAD/ CAM software, or the other two CAM software programs for which the lab has licenses.

Something had to be done.

Going Industry Standard

Manufacturing at JPL is all about precision.

The group works with PhD-level scientists, mostly from Cal Tech, to build delicate, one-of-a-kind instruments that are often the culmination of a decade or more of research. Most of the drawings are to four decimal places - true position. Cournoyer says, "For weight conservation, parts are so thin-bodied (down to 0.001") that it is sometimes hard to differentiate between a burr and the actual wall of the part." Another challenge for JPL's machinists is working with exotic materials chosen for their low co-efficient of thermal expansion.

Space is the ultimate vacuum and does not provide an atmosphere that will promote radiation of heat. Components tend to bake inside the spacecraft while cruising to a destination millions of miles away. Then instruments are finally required to perform their tasks in space at temperatures down to -455°F. So they have to deal with unique machining requirements of materials like Kovar and Zerodur.

What does this have to do with staffing? Cournoyer found out the hard way when he was trying to quickly build up staff levels during the latter build stage of the MSL (Mars Space Laboratory), now called Curiosity mission, which will launch in 2011.

He explains, "It takes somebody with finesse for precision making delicate instruments to be able to work here. Our machinists are programmer/machinists. When they sign on for a given part, they own it from the sketch to launch pad. They decide which manufacturing processes to use and write their own CNC manufacturing programs.

"All the resumes I saw from people with Unigraphics skills were looking for positions as design engineers. They only wanted to work behind a desk. I was getting pressured by upper management to grow my staff faster, but I just could not find machinists proficient in the CAM software we were using.

We had a good variety of software but it was not industry-standard software." What he did see on just about every machinist's resume coming across his desk was Mastercam experience. Cournoyer, who was previously on the faculty of WPI (Worcester Polytechnic Institute), considers himself a scientist/machinist. He was experienced with this CAM software and knew that it could easily provide the tools for precision CNC manufacturing that JPL required.

Mastercam CAD/CAM programming, from CNC Software, was also being taught in the Manufacturing Technology program at nearby Glendale Community College (GCC), which supplies JPL with some of its apprentices. So apprentices would have the benefit of using the same software that they were using in their courses.

Cournoyer made a formal budgetary request to acquire seats of the industrystandard software, and soon his staffing problems were behind him. Instead of automatically rejecting three-quarters of the machinists' resumes, he now had three times as many candidates to evaluate for each position.

Intense Manufacturing

The lucky machinist new hires and the apprentices quickly find themselves immersed in a techie manufacturing environment unlike any other. "We have 5,000 people here at JPL but only four levels of management," Cournoyer states. "We do not have departments, we have groups. Groups can be a group of scientists, post docs, two machinists, etc. It is very intense." In addition to being the Group's manager, Cournoyer is also the Section's technologist.

This allows him to sit in with key scientists from around JPL and look at the future. "This is important to me from a capital budget standpoint," he says. "It puts me in a position to influence the kind of machines JPL will acquire for meeting material and tolerance requirements going forward." Shortly after JPL obtained several Mastercam licenses, Cournoyer went back to school to learn the latest version of Mastercam, which was X2. Based on the training, he is now an SME (System Material Expert) for apprentices, who receive 4,500 hours of training at JPL, and for contract employees.

Shortly thereafter, the group hired another SME, a "true Mastercam expert." Cliff Lengtat is an experienced machinist who worked as a certified Mastercam instructor before accepting a coveted contractor's position at JPL. With two Mastercam SMEs on staff, JPL is well positioned to have the majority of its machinist/programmers ready in a few more years when the group is out of the bathtub.

Imediate Gains After acquiring its Mastercam seats, JPL was able to build its contract programming staff to a high of 23 and handle the final manufacturing push for the upcoming MSL Mission.

Cournoyer admits to jumping the gun and hiring two Mastercam machinist/programmers immediately after the budget for the seats was approved but not allocated. He said they had to struggle for a few months with other software, but they were off and running as soon as their familiar CAD software was on the network.

Much of the work is done using a paperless workflow. A major benefit of Mastercam is a proprietary kernel that allows the programmer/machinists to import Parasolid models directly without the loss of data.

Then Mastercam's ease-of-use and ultra-fine control of toolpaths make a significant contribution to the machinist/programmer's productivity in manufacturing technically complex parts.

Perhaps the most impressive immediate contribution Mastercam made at JPL was in the realm of post-processing. Cournoyer says that each of the CAM systems used at JPL had posts that worked at least adequately with 30 different CNC machines. However, none had a post that could be used in conjunction with a huge, multi-million dollar Mitsubishi 8-axis boring mill. As a result, that machine was woefully under-utilized, and often called the "big drill press." JPL asked each of the CAM vendors for its thoughts on getting a post to work with that machine. Two provided quotes, and the Mastercam reseller went to work immediately writing a post-processor. "It took a while for them to do it," Cournoyer says. "It was not a trivial assignment because it is truly a one-of-a-kind machine.

However, within a year we had a working post and had turned an idle machine into a valuable multi-axis CNC asset. In an emergency, we can and have performed a 22-hour machining assignment on that machine in 24 hours." Today, only eight of the 23 high-water contract machinists remain at JPL. Most are Mastercam-proficient. When JPL is out of the bathtub again, there may be as many as 30 contract machinist/programmers. At that point Cournoyer estimates that Mastercam will be the software of choice for three-quarters of them.

CNC Software Inc.
Tolland, CT
mastercam.com