Every service call is unique. However, recently we received one that was truly extraordinary. Tom Smith, machinist for the 1925 steamship ‘Saltsjön’, rang and asked if we could help restore the old vessel by heating rivets for new, below-deck flooring.

It sounded interesting, so we packed a Minac mobile induction heater and whizzed off to a boat dock in Stockholm, Sweden. Tom met us there, together with his colleagues Janne Lundell and Mats Söderlund.

We began with a tour of the ship, a beautiful vessel steeped in history. She had transported Stockholm
residents for many years and even served as an icebreaker in winter. Now officially listed, she was undergoing extensive renovation.

Old method, modern twist

Heat induction’s many pluses were apparent from the start. Traditional heating methods are time-consuming and uncomfortable. If you use an on-site furnace, great amounts of coal and hard work are required to keep the temperature high. What is more, traditional riveting is cramped, dangerous work. Gas is not much better. It is time-consuming, and it creates an uncomfortable working environment.

Instead, we simply brought the Minac aboard (it was easier than it sounds, it only weighs 50kg), connected it to electricity and water and started it up. Better yet, the induction coil (the actual heating tool) lies at the end of a 5m, water-cooled cable so it could easily be taken below-deck. Talk about an improvement in working conditions! Within seconds the rivets were glowing.

The work went quickly, and after a few hours we were done. A tong lifted the heated rivets, the bucking bar was positioned and a pneumatic hammer battered each rivet. Meanwhile, the next rivet was being heated.

Work on ‘Saltsjön’ was a successful combination of a proven method (riveting) and modern technology (heat induction). And the advantages of heat induction were obvious: flexible equipment, fast and efficient heating and a comfortable working environment. It was satisfying to help Tom and his co-workers and to see how modern technology can preserve living history.