by Jenny Knodell, IQS Editor
Look at the two images below. How do you think those round metal disks are transformed into that perfect, beautiful trophy? Maybe some form of molding or welding, definitely with the use of heat. If that’s your guess…you’re wrong! It’s formed by metal spinning, a process that doesn’t use heat at all and looks just like forming pottery on a wheel, only with metal. It was once considered a true art form that took skill, practice and talent. It might surprise you, but metal spinning has been around since the ancient Egyptians, to form objects like bells, bowls, light fixtures and even trash can lids. Hockey fans should appreciate this process, since the Stanley Cup itself was once a large goblet made by metal spinning.
Originally, metal spinning was performed on something that works very much like a pottery wheel, only a second person was needed to turn a large wheel that connects to a lathe (spinning part) by a belt. Only soft, formable metals were spun back before modern innovation. Hand metal spinning a perfectly cylindrical hollow shape was very difficult and took a lot of experience and patience. Each finished product, however, was a unique, hand crafted work of art with individuality and personality. By the 1930s, the first modern hand metal spinning machines were developed, and that second person needed for turning the lathe was no longer needed. Today, hand metal spinners use a hand-held tool to shape the metal on a lathe, which spins at high speeds by electric power. This method, though, is quite dangerous. Metal spinning artists have been known to lose fingers in their line of work.
Photo courtesy of Acme Metal Spinning, Inc.
Today, like most processes, metal spinning has become fully automated, eliminating the need for metal spinners. The advantages of CNC metal spinning are obvious—high repeatability, the capacity to fabricate high volumes of the same product, more complex designs, less worker injuries and lower costs. The dimensions and design of the future product are uploaded into a computer system, and the metal spinning machine follows the pre-set sequence of operations. The result? Modern products like tank heads, metal test tube holders, refractory nozzles and even some pressure vessels are fabricated by metal spinning. Even strong metals like steel and titanium are spun into perfect, symmetrically round metal products, where before, only metals like aluminum and copper alloys were soft enough.
Since the introduction of CAD/CAM controlled metal spinning systems, traditional hand metal spinning has largely fallen out of popularity. Some small metal spinning workshops still use this disappearing art form, but unfortunately, they are becoming less and less common. It really is a neat process. Decorative metal items like candlesticks and goblets are still made by hand most of the time, and some remaining metal spinning artists are trying to make a come back. There’s been a recent hand metal spinning revival effort by those who don’t want to see the process fall out of use. There are classes available, as well as video tutorials and instructional videos for anyone who wants to learn how to make their own bowl or candlestick. So if you’re interested, why not pick up a new hobby?