WORTH ITS WEIGHT

As a leading manufacturer and supplier of precious metals, the figureheads of Cooksongold get pitched technologies aplenty as they sample trade shows and conferences across the globe.

Such is the frequency of these conversations for Managing Director Martin Bach, he plays them straight, offering an honest appraisal of what has been put before him. Take Vicenzaoro 2020 in January, for instance, where he was being told all about a fully automated, ‘all singing, all dancing’ CNC machine, which was being used to make rings and other jewellery pieces in a number of different materials. “That’s not the right way to go,” Bach determined. “It doesn’t matter how good your machine is. It can be the most incredible machine, totally robot loaded with zero labour cost, if it’s not dedicated to a given alloy, my system’s cheaper.”

His assessment of 3DLab’s ATO Noble powder atomiser device at another trade show, meanwhile, was the polar opposite. So impressed were he and his colleagues of the Polish company’s patent-pending Ultrasonic Atomization technology, they agreed to optimise the parameters and enhance the performance of the machine, before readying to make it commercially available at some point this year. Customers will be able to either buy powders atomised on the ATO Noble or buy the machine outright and begin to produce the powders themselves in-house.

The ATO Noble uses plasma arc melting to turn wire material into molten material, which is then subjected to vibrations with a specifically chosen frequency, atomising the liquid metal before it solidifies to form a powder. 3D Labs says this resulting powder – which could be reactive alloys like aluminium and titanium or, more pertinently for Cooksongold, precious ones like gold, silver or platinum – will boast excellent flowability, perfect sphericity and narrow particle size. The 760 x 1100 x 2000 mm machine also promises 100% material atomisation and a minimising of material loss thanks to a filtration system that recovers it for reuse. Despite having powder atomisation capability already in-house, for a manufacturer like Cooksongold, these

WORDS: Sam Davies

capabilities and features proved too good to ignore.

“We think this technology has the potential to offer better quality powder, more tightly controlled distribution and therefore lower costs because yield is better. And with a piece of equipment which is much smaller, losses are going to be less” Bach explained. “It’s not rocket science. Precious metal is all about not losing precious metal and refining it as little as possible. Otherwise, it’s fiendishly expensive.”

Hence, much of Cooksongold’s parameter development on the ATO Noble is focused on making sure the machine is easy to clean down and ensuring material doesn’t get stuck in joints or caught up in filters.

“IT’S A FANTASTIC TECHNOLOGY, IDEALLY PLACED FOR OUR SORT OF MARKET.”

The cost of precious alloys, plus the potential need to refine the material, is what inhibits the more frequent application of the materials in 3D printing, despite them being safer to process than reactive materials. But for Cooksongold, who’s invested big in 3D printing and has launched and deployed the Precious M 080 metal laser sintering machine with EOS, printing precious metals like gold is almost unavoidable. “It looks pretty, it won’t tarnish, and everybody wants a gold piece of jewellery,” Bach explained.

So, when Cooksongold send Bach and his colleagues to places like Vicenzaoro, it’s in the hope that they come across technologies that can facilitate high-quality parts printed in precious metal and do so more efficiently. In the ATO Noble, the company believes it has found just what it was looking for. “It’s a fantastic technology, ideally placed for our sort of market,” Bach assessed. “Conventional machines for producing atomized powder are big, big things. They’re not designed for low quantity and so your losses are significant. [The ATO Noble] is much more flexible. It has the potential disadvantage of being a low volume approach, but you very rarely talk about high volumes of precious metals, so you don’t need to worry about it. You’re not producing tonnes a day; it just doesn’t happen.

“So, the fact that it’s a small, self-controlled, enclosed system is perfect for precious metals. Perfect.”