Metal AM: Challenging the Paradigm
Manufacturing Engineering: VELO3D has trademarked the term “SupportFree.” What does this mean and what kind of cost savings or improved part quality can shops expect from using your technology?
This engine combustor from Sierra Turbines previously required 61 discrete components to manufacture, but thanks to SupportFree technology, can now be 3D-printed in a single operation.
By Will Hasting
Director of Aviation and Power Turbine Solutions,
Velo3D
Will Hasting: The industry standard for 3D printing metal surfaces [without supports] is 45 degrees, as measured from the horizontal plane. That’s what most printers are capable of achieving without supports. This means, however, that any features shallower than this require a support or series of supports to prevent curling and distortion. These [support] structures must then be removed post-build, adding to cost and lead-time, and possibly jeopardizing part quality.
By comparison, we can successfully print surfaces down to 10 degrees and, in some cases, actually 0 degrees, or completely horizontal. That’s a huge differentiator, especially for parts with complex internal features, where it’s difficult or even impossible to remove these supports. Sometimes the printing process is truly support-free, where the parts are free-floating in powder, and other times, it is support-less, which means it reduces the consideration of support structures for manufacturing.
ME: Similarly, does support-free printing open doors in terms of design freedom or ease the manufacturing process in any way?
Hasting: SupportFree reduces the natural tension between design and engineering. It enables designers to think and build without constraints, and gives engineers greater latitude to extract more performance from their products and systems. For example, we recently worked with Sierra Turbines here in San Jose on an engine combustor that previously required 61 discrete components to manufacture. Because we can print at extremely low angles, we can eliminate the supports that otherwise would have been required. The result is greater aerodynamic efficiency and less air leakage. You also have a more consistent, repeatable structure, with fine meshes and smooth lattice structures that provide better fuel flow to the combustion chamber. There’s no way this part could have been manufactured without SupportFree printing in its current iteration.
ME: Are there any downsides to this approach? Slower build speeds? Higher equipment or operating costs? More challenging build preparation?
Hasting: That’s an interesting question. For operating costs, we made a back-to-back comparison on an impeller printed with and without supports. With the latter, we used 14 percent less powder, had a 20 percent faster print time, and were left with 89 percent less surface area to machine.
And yet there’s more to it than the build. SupportFree not only means greater design freedom but also less engineering time. In fact, we just spoke with one of our machine shop customers, Duncan Machine Products in Oklahoma, who told us our machine is very intuitive, far more so than CNC machining. Our system is easier to use because we know the paradigms and obstacles that have historically prevented metal AM adoption.
ME: Support elimination is clearly essential for parts with large numbers of complex internal features, as evident from your success with heat exchanger and gas turbine manufacturers, but is it as relevant with simpler parts, where secondary finishing processes can easily remove these supports?
Hasting: We at VELO3D take pride in our ability to tackle the tough parts that others can’t, but that doesn’t mean we’re not competitive on simpler parts as well. The Sapphire system prints with greater consistency and higher yield rates while eliminating all sorts of issues and problems commonly encountered on 3D metal printers. Parts of all shapes and sizes are simply more printable.
ME: Most metal 3D printer manufacturers tout their in-process build monitoring and environmental control capabilities. What makes VELO3D’s technology different?
Hasting: We designed a system that’s engineered with far more sensors and provides more insight into the build process. The data is actionable and informative, versus accumulating terabytes of data without much usability. We also developed a software suite that knocks down obstacles that might keep us from printing what we need to print, whether it’s a problem with the material, the part geometry, or a hardware constraint. The Assure system gives our customers access to all the tools and data we used to develop the Sapphire 3D printer, providing insight into the build process. And while all 3D printers generate data, you have to look at how usable this data is to the technicians and engineers using the system.
ME: You recently introduced a large-format 3D metal printer, said to be the tallest such machine available. Was this simply a matter of increasing the height of the build chamber and adding Z-axis travel?
Hasting: The Sapphire 1MZ has a 1-m high build chamber and provides the same level of process control as the original Sapphire metal 3D printer. It’s receiving a lot of attention from rocket and defense manufacturers and those in the oil and gas industry since it gives them the capability to combine assemblies that previously required welding and fitting of multiple components. This will be the case with Knust-Godwin in Katy, Texas, which is looking forward to delivery of the first 1MZ later this year.
ME: The VELO3D website claims that your Flow software “unlocks parts not previously possible with additive manufacturing.” How so?
Hasting: We’ve already discussed part complexity, so let’s focus on scalability and repeatability. Complete software and hardware integration is one of the key aspects of our technology. If you used a PC back in the 1990s, you know that the hardware and software typically came from different manufacturers. The two would often fight, and the user had to trick the system to get everything working. That situation is similar to many of the 3D printers today, and it’s what impressed me most when I first came to VELO3D—everything is integrated. You can print a part today and six months from now send that same Flow file to a printer anywhere in the world. The results will be the same, regardless of part quantity, the machine vintage, and the serial number on the laser.
ME: Metal AM has taken off over the past 10 years. What will happen in the next decade?
Hasting: One thing is parts are still too expensive, and much of that is due to post-processing costs. VELO3D has already addressed this and will continue to push our technology farther to reduce support structures and also [increase] part quality in terms of first-time yield. But what is really holding metal AM back is confidence in the parts.
For instance, a company’s metal AM team might want to use additive to make a part, but the chief engineer won’t sign off on it. Some of that reluctance is because it’s a relatively new technology, but it’s also because manufacturers have been burned with the lack of process control in most metal AM systems. They lack confidence, and the only way to get it is through traceable process data, leading to better part quality and successful build experiences. Over the coming years, that’s what we will continue to provide.