Lincoln Electric Additive Solutions builds large metal parts – including a hollow blade propeller five feet in diameter and large automotive stamping dies and molds — using its inhouse wire-based metal additive manufacturing technology. While using its 3D printing technology improved lead times, the size of the parts it was dealing with and the complexity of some of the designs created measurement challenges.
“The fact that we were going to make very large parts, measuring in feet and weighing sometimes thousands of pounds, meant that a coordinate measurement machine was not going to cut it,” explained Mark Douglass, business development manager, Lincoln Electric Additive Solutions.
So the Euclid, OH company, which was launched mid-2019 by well-known industry parent Lincoln, looked at alternatives. It decided that 3D scanning fit the bill because the technology was capable of providing a full 3D surface model of the part in question. That model could then be compared to the original CAD model. The company eventually settled on Levis, Quebec’s Creaform and its hand-held MetraSCAN 3D technology.
Creaform’s MetraSCAN 3D features 15 laser crosses making it capable of tackling large scanning areas. It has a measurement rate of 1,800,000 measurements per second.
“It is very fast. We can measure our parts in a manner of minutes,” said Douglass, adding that MetraSCAN’s easy portability addresses Lincoln’s need to take the measurement tool to the part since its parts are large and heavy to move.
The MetraSCAN also helped Lincoln deal with the complexity of design required for some of the parts it produces.
“A lot of times we have parts with unique features and we need to make sure those features are exactly where they need to be,” said Brad Barnhart. “What makes the Metroscan great is that it’s a non-contact solution. We are able to scan our parts and verify dimensional quality at any time during the manufacturing process, even mid print when the part is still too hot to touch.
Lincoln’s wire arc additive manufacturing combines gas metal arc welding (GMAW) with sophisticated automation. The process involves the use of 3D CAD software and the application of a robotic arm with a GMAW torch, which puts down successive layers of melted wire feedstock onto a multi-axis positioner to form a single, fully formed part. The process is ideal for parts larger than a basketball and can be scaled to several meters, the company says.