Where blue-collars and physics scholars meet
| 02 April 2003
To the casual observer, the machine shop on the first floor of LeConte Hall is like most others of its kind. Aproned workers wearing safety goggles are bent over bulky machinery as the high-pitched screech and acrid smell of metal-cutting-metal fill the air.
But any similarities Berkeley’s physics department machine shop has to its commercial counterparts stop there. Here, highly trained craftspersons — working side-by-side with world-class scientists — create delicate and precise instruments that will be used in cutting-edge experiments.
“Their support of our research is so crucial,” says Dmitry Budker, associate professor of physics. “Every piece we have them make is totally new and different. We’re always trying to break new ground in our work, and they’re right beside us to help make that possible.”
Budker and assistant researcher Valeriy Yashchuk recently worked with machinists Alex Vaynberg and Dave Nguyen to create a set of nesting drums — the largest of which is some three feet wide — made from CO-NETIC, an expensive nickel-iron alloy used to provide electromagnetic shielding. The device will allow the accurate testing of high-sensitivity magnometers without interference from the earth’s magnetic field, explains Budker.
The instrument was hand-fabricated by Vaynberg and Nguyen by cutting, rolling, pressing, and welding the metal. The pieces were then gently pounded with a special hammer to meet the researchers’ exact specifications for thickness and shape.
The machinists build items for all the disciplines within physics, including nuclear, atomic, plasma, condensed matter, biophysics, and astrophysics.
“We start with a general idea of what we want, then talk directly to the machinists about what we’re trying to accomplish, and incorporate their ideas into our design,” says Budker of his collaboration with shop staff. “We work together from initial concept to final product, often modifying as we go along.”
Principal mechanician Steve Butler, like most of his colleagues, started his career working in commercial machine shops, but found himself bored by the industry’s mass-production process.
“Most machinists dream of working in research and development, which is why I was so happy to get hired on at the university,” he says. “Now I can use my creativity and technical skills to help scientists increase their understanding of the world.”
Butler is one of seven machinists (plus one welder) in the physics machine shop, which occupies more than 5,000 square feet in LeConte Hall. The shop’s floor was specially built to withstand the heft of the machines, some of which weigh more than six tons.
The machinists and their equipment perform two basic functions. The first is milling and drilling, a process whereby material is held stationary while machinists carefully maneuver tools to cut it, either through computer commands or by hand. The second is turning, in which stationary tools perform interior and exterior cuts on a rotating piece of material. Using just these operations, though, the most intricate and exacting products can be made.
The machinists work with a variety of raw materials, depending on the requirements of a given project. These include basic brass, stainless steel, and aluminum, as well as high-tech plastics like Vespel, and Macor, a ceramic substance prized for its insulative qualities. The scale of work also varies, from super-small to massive.
“I’ve drilled holes that were 50 microns in diameter — that’s one two-thousandths of an inch, as thin as a human hair. The bit is so tiny and delicate, you can break it by breathing on it wrong,” says Butler, only slightly exaggerating. “At the other end of the spectrum, we made a 15-foot-wide metal gondola for a balloon that cruised the stratosphere, some 130,000 feet above the earth. It took up the whole corner of the shop while we were working on it.”
Machine shops exist elsewhere on campus to assist scholars in other disciplines, including chemistry, optometry, and mechanical engineering. Regardless of the subject matter, the opportunity for machinists to have an impact on scientific research is gratifying, says Peter Thuesen, Butler’s co-worker in physics.
“I just love the one-on-one interaction with the professors,” he says. “They’re passionate about science, and I’m passionate about machining. To be able to marry these two professions is very rewarding.”