Some disassembly required – department dedicates the heart of a retired workhorse to outgoing president

Bob Berno tried hard but couldn’t find any takers for a 39-year-old magnet that stood two metres high and weighed hundreds of kilograms.

The 4.7 Tesla superconducting magnet had been the heart of a 200MHz nuclear magnetic resonance (NMR) spectrometer – generations of undergraduates and researchers had used the scientific instrument to analyze chemical compounds.

Built in 1986 and first used by Ontario Hydro, the spectrometer made its way to McMaster in the late 1990s. In 2002, it was moved to an undergraduate teaching lab in the Arthur Bourns Building.  Thanks to a console upgrade, the spectrometer recorded high quality data for another 20 years. “For many chemistry undergrads, that workhorse spectrometer was their first introduction to using this powerful chemistry tool,” says Bob, who’s responsible for maintaining eight NMR spectrometers as manager McMaster’s NMR Facility.

The time had finally come a couple years ago to retire the workhorse and replace it with a sleeker and smaller benchtop version with modern features and functions. Bob found a home for the defunct spectrometer’s electronics but no one wanted the massive magnet. Shipping it off to the scrapyard felt like a waste but seemed to be the only option.

Bob first needed to get the magnet out of the lab so he reached out to Jim Cleaver in the Engineering Shop. Jim and his team knew how to move large, heavy and fragile equipment out of tight spaces. Jim said he’d move the magnet and store it until Bob figured out how to get rid of it.

That bought Bob some time to come up with a plan. He knew that students and researchers using spectrometers often wondered how they worked. “All of us are kids at heart.” Bob found posts online of magnet cross-sections, sometimes done successfully and often times not.

The magnets are like Russian nesting dolls – “concentric cans within cans wrapped in insulation” explains Bob. Taking a blowtorch to the magnet’s outer layer would damage the inner layers – it would take precision work by skilled hands. Bob asked Jim if he was up to the challenge of slicing open the magnet to reveal its inner workings. Bob had some budget and Jim and his team had some free time between other projects.

“Bob didn’t want the magnet to go into the dumpster,” says Jim. “I thought it was a cool thing to save so we decided to give it a try. It took longer than we thought.”

The shop had the tools and the talent to disassemble the magnet, hoists to lift and move the heavy pieces, blades to cut cross-sections out of the individual pieces and the patience to reassemble it. They started out by working off a couple of photos Bob had downloaded from the internet but then a co-op student in the shop went online and found instructions on how that exact model of spectrometer had been put together.

As a fellow tradesperson, Jim was impressed by the quality of work that had gone into assembling the magnet.

The engineers who assembled the magnet also had an artistic flair – they had drawn a flower on the solenoid coil, knowing it would likely never be seen. Bob’s tried to find out who drew it but the clandestine artist’s identity remains a mystery.

Bob wanted to publicly display the cross-cut magnet. Parking it in the ABB foyer next to the Elements at McMaster interactive periodic table seemed like  the perfect spot.  While he usually begs forgiveness rather than ask for permission, Bob thought he should first pitch the idea to Gillian Goward who was then the chair of the Chemistry & Chemical Biology department and is now the Faculty’s Associate Dean of Research. She not only agreed on the location – she thought it would make the perfect gift for David Farrar who had decided to conclude his tenure as president at the end of his five-year term on June 30 and return to his roots as a researcher. David is a chemist and will continue to hold a faculty appointment in the department.

The magnet was unveiled at a dedication ceremony with a plaque recognizing David’s support for research, including core facilities like the Nuclear Magnetic Resonance Facility.

“It doesn’t get better than this,” said David after the magnet was unveiled. He told the audience of students, faculty and staff about first using a spectrometer back in 1972.

“I’m glad that our old magnet has a new life as a repurposed teaching tool,” says Bob. “For researchers who’ve ever wondered about the hidden forces that let spectrometers unravel molecular mysteries, all’s been revealed thanks to Jim and the team in the Engineering Shop. It’s definitely worth a visit.”