People-powered prototypes

Since 1953, Los Alamos National Laboratory’s Prototype Fabrication (PF) division has operated out of the same building: a 153,000-square-foot structure where, for more than 71 years now, the hum of machinery has filled the halls. The machines here have always been state of the art, but of course, what’s considered state of the art has changed through the decades.

Today, PF’s machinists operate millions of dollars’ worth of computer numerical controlled (CNC) machinery, coordinate measuring machines (CMMs), and the most advanced computer-aided design (CAD)  and manufacturing (CAM) software available. Using this high-tech equipment, PF produces and inspects more than 15,000 critical parts annually for national security research and development. But, according to the engineer leading many of the PF’s machining functions, the machines are not the key to success.

“It’s all about the people,” says Ray Guffee, PF division leader.

Employees working in the division’s eight machine shops manufacture pieces and parts for scientific and engineering prototype devices and systems. The division’s approximately 120 employees work with CAD, CAM, and CMM inspection software tools to program and operate CNC machinery. They are versed in reading designs and spend their days helping create and inspect parts that support the development and maintenance of the nation's nuclear stockpile.

“What we do is extremely important,” says Mark Smith, who works as a machinist in the division’s main shop, which exclusively handles classified parts. “There aren’t many places in the country where you are exposed to classified manufacturing. Managing the daily logistics of keeping classified components safe and secure can be challenging.” 

Smith’s job involves creating one-of-a-kind parts that are used for experiments. He also develops new ways to build and handle those parts—including a vacuum system for holding parts during the machining process. “There’s always something new to learn, and the field of machining is constantly evolving,” he says. “You have to stay ahead of the curve and embrace new technologies and techniques.”

Guffee says the division’s state-of-the-art equipment and sophisticated processes allow scientists to design parts with specific research goals in mind. As a research and development facility, PF often makes only one or two iterations of each part. Staff work closely with the engineers and physicists who lead experiments to ensure the final products meet their goals. “We fill a service role; anyone at the Lab can be one of our customers,” Guffee points out.

“We are constantly trying new things,” says Jose Olivas, the supervisor of the machining shop for depleted uranium. “The physicists are always driving us to the next level of perfection. Their goal is to remove as many variables as possible so they can get good data.”

While the physicists aim to remove variables, Guffee’s goal is to remove any obstacles to his employees’ success. As he walks through the main shop dressed just like his staff members in a plaid shirt, jeans, and steel-toed boots, Guffee greets and visits with the employees, asking about their work and also about their families and weekend plans. He says building a positive work culture is the key to better performance. “Details and communication really matter.”

Motivation and materials

PF machinists work with many materials, including aluminum, steel, tungsten, tantalum, high-density foam, acrylics, and plastics, as well as pyrophoric materials that can ignite. Three of PF’s eight shops are specialized, meaning they are dedicated to working with specific, potentially hazardous, elements, including depleted uranium and beryllium. Although PF does not handle plutonium, one shop exclusively machines parts used by the Plutonium Fabrication team, which supports the Laboratory’s plutonium pit mission.

The equipment used ranges from older manual tools that can rough-cut pieces to high-tech computerized lathes, mills, and grinders. “Often one machine can perform a variety of tasks,” Guffee says. “The machinists must determine how to use the machines to produce the parts in the most efficient and precise manner possible.”

One of the shops in the division recently built parts for a first-of-its-kind series of plutonium-imaging experiments at the Lab’s Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility. These experiments, conducted in May 2024, represent the first plutonium tests carried out at DARHT, which consists of two linear accelerators that produce high-powered x-ray images of materials exposed to a variety of conditions.

“There were more than 100 drawings of parts and assemblies for the experiment series,” says physicist Matthew Snowball, who led the tests. “Prototype Fabrication came through in a really big way for us—machining the parts for the containers that hold the plutonium. Our engineers kept a large spreadsheet to track the status of the work from drawings, through checks, to procurements and part production.”

Ross Roybal, who supervises the shop that worked on this project, says he found the work quite challenging. “There were many parts that had never been built before or required specialized tooling,” he says. “Our machinists had to work closely with the engineers and scientists as they revised their drawings on a tight timeline. It took a lot of collaboration, which paid off because the experiments were a success.”

From design to realization

Joseph Corriveau is the only fabricator in the PF division. His job involves bending, cutting, punching, and welding metal to make finished parts. Corriveau describes his work as “problem solving with a prize at the end every time when I make the final part.” As a fabricator, he uses laser cutters, rollers, and press brakes to transform flat sheets of metal into parts and components. He holds up a small metal bracket and explains, “It took six or seven development parts to make this final piece.”

While Corriveau usually works with drawings or models created on the computer, Alex Galindo, another machinist, says sometimes scientists bring him sketches on napkins or sticky notes. “It’s important to be able to look at a napkin sketch and visualize a three-dimensional object,” says Galindo, who makes specialized precision metal parts for weapons production tests.

Guffee notes that Galindo, a graduate of the Lab’s machining apprenticeship program, has mastered a diverse set of skills through targeted hands-on training. “The best machinists have exposure to a lot of different settings and have worked with a large variety of machines and parts to be made,” he says.

The move toward modernization

Guffee says the PF division’s current focus is on modernization. “This building was constructed as a machine shop in 1953,” says Guffee. “Now, we’re still a machine shop, but we have moved into modern times.”

Even tool storage has become state-of-the-art. Gary Monce oversees 175,000 items and tools using vertical computer-controlled storage and retrieval systems. Automated extractors retrieve parts stored in the 35-foot-high device, making it simple to monitor and replace consumable pieces and maintain inventory for every need.

“I can’t make a part, but I sure can keep track of stuff,” Monce says.

Another area where the division takes advantage of modern processes is additive manufacturing. Four additive manufacturing machines are used to make plastic fixtures to hold parts for machining and inspection. “Whenever we can embrace new technology, we do,” Guffee says.

One of the most advanced areas in the division focuses on inspection. Every part must be inspected to ensure it meets precise specifications. This work is done using sophisticated CMMs and scanning devices that measure parts to the micron. “A strand of silk in a spiderweb is six microns in width, and we measure to one micron,” Robert Mietz, an inspection engineer says. “These machines are incredibly accurate.”

Because of the classified nature of many parts, the Lab’s inspection engineers must calibrate and maintain their own machinery. “We had to go to Germany where the CMMs are built to get trained to do calibrations on the inspection machinery,” explains engineer Frederick Garcia. “It is extremely challenging work.”

If a part fails the inspection step, it must be adjusted or remade. Irving Vasquez is a dimensional metrologist who is responsible for measuring, calibrating, and inspecting parts. He also trains the apprentices to correct errors. “Nobody likes to be told to go back and redo things,” Vasquez says, “but we’re all friends, and it’s how they sharpen their skills.”

Guffee points out that with measurements to the micron, the PF machinists can’t cut corners or take anything for granted. “Our work is an essential component of the Lab’s research and development work underlying national security,” he says. “All the people in our division take that mission seriously and are committed to doing their best.” ★

Voices of machinists

Prototype Fabrication staff share thoughts about their careers.