Renishaw is a company that specializes in 3D shapes. The UK firm is probably best known for measurement probes—the devices that let CMMs and CNC machine tools locate, inspect and scan objects in 3D space. Now, the company has announced its investment in altogether different 3D technology—technology for generating 3D shapes. Specifically, Renishaw plc has acquired the entire share capital of MTT Investments Limited and its subsidiary MTT Technologies Limited. Also a UK company, MTT specializes in rapid prototyping and additive manufacturing equipment—notably including selective laser melting machines. Through selective laser melting, functional, solid metal parts are built up by adding minute layers of metal, one atop another.
The acquisition represents a dramatic expansion of Renishaw’s product range. Yet the acquisition is also a natural fit, in part because 3D metrology and additive manufacturing fit together so well. With scanning technology, a complex sculpted form could be precisely captured as a digital point cloud. Then, with selective laser melting, that same form could be generated in metal. No intervening tool is needed for this—that is, no chip-making cutting tool, and also no tooling such as a die or mold.
One other reason the acquisition is a natural is because Renishaw has been interested in additive manufacturing for a long time. Nearly three years ago, I visited the company’s additive manufacturing lab in the UK, where personnel were already developing expertise that was being applied in the company’s own production. With last week’s move, Renishaw seems to be saying that it expects many other manufacturers will discover the same value it has seen in additive manufacturing technology.
In MTT’s selective laser melting machine, solid parts are precisely built up from one thin metal layer at a time. Geometries can be created easily that would be difficult or impossible to create through CNC machining.
I snapped this photo during my visit to Renishaw’s additive manufacturing lab nearly three years ago. The part in the background is a component built from machined parts, while the part in the foreground shows how additive manufacturing might produce a component for the same function. With additive manufacturing, build time is relatively unaffected by geometric complexity. The part in the foreground is resin, but selective laser melting builds comparable parts out of metals including titanium, stainless steel and tool steel.