Advanced Manufacturing

Rapid Prototyping:

How to Monitor and Verify Quality

As rapid prototyping and metal 3D printing support the creation of new kinds of automotive components like hubcaps and side air vents, designers need to know that their fabricated parts have been made properly and according to design specifications.

The beauty of 3D printing and rapid prototyping? When you’re printing on a layer-by-layer basis, 100 microns at a time, you’re able to see exactly what’s inside the part.

In a Tech Briefs Q&A with readers, Matt Sand, President of the Gardena, CA -based manufacturing company 3DEO, explains how his organization monitors the builds of 3D-printed parts and components.

You can watch the build as it’s being built. And you can track, log, and trace back all of the details.

“We have a number of sensors and cameras in the machine as they’re printing parts. We have closed-loop feedback systems in the print,” said Sand.

In the Tech Briefs “Answering Your Questions” article, Sand reviews the rapid prototyping inspection possibilities, post-print: visual systems, co-ordinate measuring machines (CMMs), touch probe systems, and even old-fashioned gauges and calipers.

3D printing offers more inspection possibilities than traditional manufacturing techniques like injection molding.

“With injection molding, you have the mold, you inject the material, and you’re not really sure what’s happening inside the part,” said Sand.

Kevin Brigden, an Applications Engineer at the UK-based engineering company Renishaw, also weighed in on the reader question and shared his opinion on what data should be collected —and for how long.

In the Tech Briefs response, Brigden explains how to use in-process monitoring data to compare a part, in real time, to a known “good-quality” part.

The approach, essentially: Sensors can monitor system behavior like temperature, gas flow, and pressure – and monitor the rapid prototyping process itself.

Two photodiodes, for example, watch for plasma emissions and infrared emissions. Additionally, power received at the print bed can be compared to power demanded by the laser.

“So, we can actually check that what is happening at the bed is what we asked the machine to do,” said Brigden.

Also: see how acoustic sensors are being used identify sonic events during a build. A sonic event may not tell you exactly what happened or what it even means for the build, says the Renishaw pro, but the detection will help you zero in on areas of interest, which has traditionally been the main difficulty with in-process monitoring of additive manufacturing.

Learn how acoustic sensors have helped Brigden and his team cut down on data storage and improve rapid-manufacturing processes.

Answering Your Questions: How to Confirm Metal 3D Printing Accuracy and Quality